Mustang V6 Autocrosser named Mistress

About a week ago about a dozen autocrossers from SCCA Lake Superior Region descended onto Sawyer Airport in Michigan’s Upper Peninsula. But we were not there for an event. We were there to get background checks and some basic TSA training.

Sawyer security has been upgraded so now the perimeter of the course has to be guarded by TSA certified people to make sure no baddies get into the operating part of the airport during an event.

We will have to be diligent; TSA could actually test or challenge us by trying to cross the line. We will prevail. Why? It is worth it. This is one of the best venues in the upper Midwest.

This airport was once K.I Sawyer AFB and has 20 some acres of wonderful concrete to play on. LSR re-creates national courses there. Last year I think we ran the 2013 East course or something like that. Yes it is way the hell up in the middle of nowhere (otherwise known as Gods country) but it is a great drive and besides it is only about three hours from me. We should be certified by the first event there in July (hopefully).

This weekend Mistress will be sorting out a course at the east end of the U.P. at Kinross Airport (Formerly Kinross AFB). The course is smaller than Sawyer but I think you can still squeeze a national level course on it (or something close to that). It is about 16 acres. I have not run it in a few years. This is for the “Yooper Cup”. Trolls (those that live below the bridge) against the Yoopers (including Canadians and folks from Wisconsin, etc.) Basically it is Great Lakes Division against Central Division.

Central Division is the underdog because there are some serious ringers down in the Great Lakes Division. The event is normally held at the Continental Tire Test Facility (another wonderful venue) but it is under construction this year.

Because of some family matters in the Detroit area prior to the event I will be circumnavigating Lake Michigan (300 miles long) in Mistress for this trip. Overall the trip will add up to about 20 hours in a noisy car with very stiff suspension. Road Trip!

Last weekend my wife and I drove 1380 miles around Lake Michigan in Mistress (it was brutal). We visited relatives in Detroit and went to a memorial for an uncle then up to Michigan's Upper Peninsula for Autocross at Kinross airport (formerly Kinross AFB) on 16 acres of wonderful concrete. Ten runs Saturday and 6 more on Sunday. I finished mid pack in Pax. Beat my friend Jay in a similarly equipped GT on Saturday afternoon (He got me by 2+ seconds overall for the weekend though). Great Fun. Here is a link to my best run Saturday afternoon. How many mistakes can you find?

Kinross - June 2017

Mistress has been running a little hot. You can’t tell with the temperature gauge on then instrument cluster because it only goes high when things are about to melt down. However I have a Bluetooth OBDII transmitter connected to my phone. It is very useful for monitoring and troubleshooting.

The thermostat opens at about 200 DegF but the car was running up around 210 and losing ground if you used the AC. After flushing out the radiator (still stock) I discovered the air inlet side was full of cottonwood fluff and such.

After a good cleaning it is all working fine again. Last year for Christmas my son Nate gave me a little tool for removing radiator/heater hose clamps. I was skeptical at first. But after using this thing I am wondering where it has been all my life. Holy Crap is it useful! If you have one of these no need to read on. If you don’t and if you work on cars – You want one. 100% better than pliers.

It is a ratcheting cable clamp that opens/closes the spring clamps on hoses. Works great. $50 at NAPA. Hose Clamp Tool

If you are an autocrosser in the upper Midwest USA or Canada/Ontario there is an event on July 15-16 at K.I Sawyer Airport (formerly AFB) near Marquette Michigan. This is one of the best venues in all of the Midwest. - 20 acres of very good concrete.They will set up a previous Nationals course on it. Because of the location there will not be many people so you get many runs (last year I think I had 24 runs over two days).Come on up and get ready for Nats. SCCA-Lake Superior Region.

SCCA_LSR - K.I. Sawyer Event Page

Second major event for Mistress in 2017 - KI Sawyer Airport. We finished mid pack at about 50th percentile in raw and pax times. This is an improvement and is looking like it might be a trend. Had a blast with 12 runs each day on a replica of the Nationals 2016 East course (You read that right - 24 runs total).

Here is a video of my best run on Sunday (running the course backwards).

K.I. Sawyer Best Run   The in the background is a stranded Russian tanker plane. Google it - interesting story. Going back August 12-13.

I did some data logging  with the lap top on a couple of runs. Here are some snippets of things I learned from the data for what it is worth: - Torque converter catches up with the engine on launch about 22 mph. It spends much of the time doing its thing torque multiplying whenever the car slows down. - Torque converter clutch only engages sporadically, once or twice per run and only for a second or two in the high speed portions. - Tire spinning (after start) was much was less than at earlier events. I believe this surface is stickier (except Saturday afternoon - too hot). - Engine coolant gained about 8 degrees on a run. The biggest rise was just as/after the run finished. It took about 30 seconds to a minute to cool back down to low speed fan off (203 DegF) after stopping. After that it just cycled up/down a couple of degrees on the fan. That is all for now.

Camber Adjust Tool SN95 Mustangs have a modified McPherson Strut front suspension like many/most cars on the road today. McPherson Struts have a disadvantage in that when the car leans over in a hard corner it rolls out the camber on the outside tire (because the top of the strut is attached to the body).

Mistress body rolls about 5 degrees or so in a hard corner which s enough to require some aggressive camber. I have installed camber bolts and slotted the mounting holes so that when the struts are pushed all the way to the outside camber measures about -0.5 degrees and when pushed all the way in it measures about -2.5 degrees.

This way I can drive around all summer with the car set to near stock camber and then quickly switch to “autocross alignment” at an event simply by loosening the strut plates with a 15 mm socket. The car falls to the aggressive alignment on its own. Takes about two minutes. It took quite a bit of fussing to get this set up right.

Also, with the plates pushed in with no other changes you get a very slight toe out (good for autocross, not for driving around). The problem with this is that at the end of the event when it is 90 degrees and I am burned out and exhausted I have to jack the car up to get back to normal alignment. So I made a tool. It is a simple angle iron bracket and screw that fits into a ¼” hole drilled into the inner fender liner and pulls the top of the strut back to the outboard limit (or anywhere you want to stop along the way). The washer (painted red) is beveled on the inside of the hole to get a purchase on the strut threads and not damage them. To pull both struts out takes about 5 minutes and you do not have to jack the car. It is crude and could be better looking but effective.

The nut on it is also 15 millimeter so you do not have to change sockets during the process. If tire temperatures indicate you need to remove some camber between runs you can do it quickly. I have been using this thing for several years now.

That is one of the most clever ideas I've ever seen

That's f-in' brilliant. I love it.

So I dodged a bit of a bullet this weekend. I was up at K.I. Sawyer on Sunday with the SCCA Lake Superior Region. On the 9th run Mistress started making a grinding noise from the rear during hard left turns (Egad what the hell is that!). I made a 10th run and truncated it when the grinding got worse. Went off to the side of grid and messed about a little trying to re-create it. Looked under the car. Measured the temperature of the differential and back brakes - all normal. Went out for a tentative 11th run at 80% speed and cut it short also. Something was very wrong but only in hard left autocross turns. Skipped the last run. Came in mid field again in Pax Packed up and drove 180 miles home with no incident and no noise. Could not re-create the problem on public roads without risking life and limb. Brakes working splendidly. Only happens in 1g left turns. So now Tuesday night I finally have enough energy to put the car up on the lift and look for trouble. Bad thrust bearing in the dif? Brakes coming loose? Tru-trak disintegrating? Something bent and rubbing? One of the mufflers had pulled loose from its hanger and was rubbing on the drive shaft. That is a relief. I really did not want to pull the dif apart right now because then I would want to change the gears and I don't want to spend the money on that right now. I got it re-hung and fashioned a makeshift clip to keep it there. I think I will get some split clamp collars to make it more professional and keep all the hangers in place. G forces pulling the exhaust off of its hangers. So it turns out the problem was sort of a Muffler Bearing. Sort of...

I always put a hose clamp there to keep that from happening. I figured if it takes the hose clamp off, god meant it to be open headered.

In reply to Dusterbd13:

And now I know...

I have not logged in for a while, which might be typical for end of season. My season ended fairly abruptly in mid September. We were at an autocross at the former Kinross AFB in the eastern Upper Peninsula of Michigan (about 5 hours from home).  It was a two day event with Lake Superior Region SCCA.

On the first run of the first morning I was on course with a novice riding along. She had never been on an autocross run. She was very quiet before and during the run then: “Holy Sh-Expletive Deleted!!” she screamed as we dropped down to grid speed coming off course. Hooked for life right then and there.  Her laughter was cut short just before we pulled to a stop in grid when Mistress let go with a loud CRUNCH and the entire front end jumped about an inch.

Everyone nearby in grid turned around and stared at the car and said "What the hell was that?" in unison. Ten minutes of crawling around/under the car did not turn up any problems. I went out for five more runs that morning.  It jumped and banged two more times - just enough to see a trend. Always after the run, always with a slight steering correction pulling into grid.

Have you guessed the problem yet?  At lunch I jacked up the car. Driver side ball joint seized and twisting loose in the control arm. Under hard left turns the wheel unloads and, free of the rebound from the damper, the control arm can bounce up onto the top of the ball joint. Sometimes it would hang up there on the boot. Talk about alignment issues! The spring would push it down with a bang when the car was settled and I turned the steering wheel.

Not a difficult fix. My wife and I decided we could drive home but it would be wise to cut the weekend short. So I got six runs in out of a potential 24. I did take eighth place with LSR this season! (small pond).

That was the end of my season because I had to go on a long term field assignment out of state for work. I just got home last week. Missed several local events.

So – Mistress has been sitting on the lift for over a month with a broken wing and I have some extra overtime money… What to do, what to do… the car just needs a new ball joint and control arm but…  RACE CAR LOGIC applies here:    New K-Member and front suspension!!

I am working with Maximum Motorsports to come up with the right combination of parts for this car and how it is used. These guys are wonderful and very knowledgeable (thanks for the recommendation Jay).

Plans for this winter are new K-member and coil over front suspension from MM with perhaps a few other parts as recommended. Switching from the stock 323 to 373 gears (15% increase in torque at the wheels) with a diff girdle and possibly new axles. Move the battery to the rear passenger seat floor pan and a rear seat delete. I also have some photos of a modified harness bar install and a few other things will share.

Jingle bells, jingle bells…

This is still one of my favorite builds here.  Love the progress and some great thinking with you camber tool.

Thanks Adrian! I love your Avatar!

Mistress Suspension Re-Work (and some rocket science I learned recently)

My order has been placed for a new K-member and Coil Over Spring set with new rear sway bar from Maximum Motorsports. This entry (it is a long one) is to try to explain (as best I can) how these parts configured and why they were chosen after much consideration and input from a master.

The overall reason for this change is to fix the existing geometry issues noted in earlier posts, allow more adjustment in the suspension, reduce friction and weight (~50#). (And the left front ball joint and control arm are broken so, why not now.)

After several long emails and a long questionnaire from Jack Hidley at MM we arrived what to buy to get the best bang for my buck.  He also asked me to send some photos of the car on course taken from the front.

Here is a quick summary of answers to all of Jacks questions for the existing set up and how the car is used. Then we will look at what Jack recommended and my understanding of why.

2002 Mustang Coupe, Base, Tires 255/40R17 on 9” wheels front and back

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Engine modified with max engine torque estimated at 240 Ft-Lbs. (not dynoed yet). May supercharge someday with a target HP just over 300 at the wheels.

Weight of car –Roughly stock – 3200#

Front Dampers  Bilstein V36-4138 in stock location – (These are suitable for coil overs)

Front Springs  HR Sport (490-575 rate) in stock location

Front Sway Bar Summit solid 1 – 3/8”

Stock Front Spindles

Stock Front Control Arms

Rear Dampers  Bilstein BE5-6418-H4.

Rear Springs Ebach Pro-Kit in stock location

Rear Sway Bar Summit 1” attached on the rear control arms.

Rear Pan Hard Bar by MM.

Rear Lower Control Arms Stock.

Custom longitudinal upper arms (I sent photos to Jack).

How is the car used: Street and Autocross. No Drag Racing. Driven to work in summer. Driven to Autocross events sometimes several hours away. Typically 110 to 140 Autocross runs per year.

Other – Keeping current dampers for now (and saving $400). 7.5” diff kept for light weight (50# lighter than an 8.8). Detroit Tru-Trac in dif.

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Right up front, Jack told me we have to look at both ends of the car to do this properly. So, here goes…

For the Front: Jacks analysis was that the car is sprung little bit too stiff in the rear OR soft in the front. If I keep the same dampers then the front springs should be stiffened a little. He recommended increasing the Spring Rate about 33%. Jack indicated that in spite of the stiffer Spring Rate ride quality would be improved by the lower friction set up with the coil overs and K-member. This would also increase understeer but that would be counteracted by the improved geometry.  The coil over springs recommended were:  200 lbs/in x 12" x 2.50" this would give a level ride.  

For a discussion of understanding Spring Rate see this link to a forum piece Jack wrote:

http://forums.corral.net/forums/16630714-post11.html

For the Rear of the Car:   Jack lead me through a good discussion on the modified four bar link set up I have (five if you count the Panhard). What I learned is that even with my set up there is still some binding. It is much better than the stock angled upper arm arrangement but it is still there. The binding would happen during cornering when the axle is square on the pavement and the car is leaning left or right.

The reason is because the upper arms are shorter than the lower arms and because of the angles the arms are placed in relation to each other. Due to this geometry when one side of the car raises in a corner it causes the axle/pinion to rotate one way (pinion tipping down or up). Meanwhile the other side of the car is lowering and the unequal geometry is causing the axle/pinion to rotate a different amount or possibly in the other direction. The axle/pinion can’t do both at the same time so it is basically twisting/binding.

To help me understand Jack sent me to SECTION THREE of his post at the link below.

http://forums.corral.net/forums/16630714-post11.html

After reading that (three times or more), he asked I look at the YouTube video linked below.  He also advised to ignore the comments after it. Many of the commenters were completely lost (in their defense, its complicated).

https://www.youtube.com/watch?v=Nj8afw8QXXk

This next section is pulled, almost verbatim, from Jack’s comments:

In the above video, the presenter articulates both a parallel and nonparallel unequal length 4-link. From watching the video it is very apparent that the nonparallel version causes the axle tubes to be forced to twist as the rear suspension rolls because each side of the differential housing is forced into a different pinion angle. When the control arms are parallel, but unequal length, this still happens, but to a smaller degree so it is more difficult to see. The ONLY 4-link rear suspension which is 100% nonbinding is a parallel, equal length, 4-link where the Roll Center from the lateral constraining device (PHB, Watts link) is at the axle housing centerline.

The more bind exists due to the geometry of the suspension and non-axial stiffness (3a from above link) of the bushings in the control arms, the more the axle housing is forced to twist. This results in greater compression/tension loads in the control arms and more loads in the control arm mounting points. Changing the stock Quadra-link rear suspension to make the UCAs parallel, removes a lot of the geometric bind, but it doesn't make it perfect.   

The engineer that designed the Steeda 5-link (which my rear suspension is based on) made sure to keep enough total compliance in the control arms bushings, so that there would be minimal bind. Virtually the only SA rear suspensions that are 100% bind free are a 3-link and a Torque Arm, if the Torque Arm front mount is designed correctly.

So – Although my suspension design is much better than stock it still has some inherent bind. A saving grace in my suspension arrangement is that I have currently left the original lower control arms and rubber bushings in place (very soft) AND my upper control arm design has some compliance in the dual urethane bushings on the front of each link.

He also mentioned my upper links would be slightly more compliant if I reversed the upper links and put the Rod End with Delran bushing on the front or put rod ends at both ends. If I did double rod ends I should leave rubber bushings in the lower arms (see binding discussion below).

A  MAJOR take away that might be missed in this discussion: If you have a Mustang like mine or any car with a similar rear suspension -->  Your suspension binds in curves (at least a little)…

Unless you have perfect geometry (and I bet you don’t) you MUST leave some compliance back there. Putting Delran, Spherical Bearings or hard urethane at all eight link ends can increase the natural binding forces and create handling or structural problems such as damaged axle welds or cracked torque boxes, etc.

Jack took pains to make the points above because:  1 – I did not totally understand and I asked. 2 – I talked about purchasing the MM Lower Control Arms that have adjustable spring perches (MMRLCA-106) in the next round of mods so that I could use some scales and properly weight jack the car. He made sure I understood to put urethane in both ends of the Upper Control Arms to keep the overall compliance I have now.

As to the comment on 3 links with torque arms being the only true non binding design: I suggested that perhaps I should abandon my Five Link someday and go in that direction. Jack felt that with the power levels my car generates now and in the future it would not be an issue to keep them. He also indicated they are lighter than a torque arm (makes sense).

Jack recommended I leave the front sway bar as is, even though it is fairly heavy, and stiffen the rear sway bar.  Because the rear bar is mounted to the lower control arms and not the axle and frame it is not as efficient as it could be. I concur in that Mistress tends to understeer in long sweepers when pushed too hard. He recommended an adjustable hollow tube bar that is 1.25” diameter with a 0.095” wall thickness.

Part# MMRSB-8.1 adjusted to full soft is 3.2 times stiffer than my current bar and adjusted at full stiff is 4.2 times as stiff. I may have to make some minor adjustments to my upper control arm towers to make room for it (no problem). The weld in version will fit better because the bolt in version has install clearance issues with my model year.

So that’s the long story of it. If you read this far I hope it was worthwhile.

If you are planning similar changes to a similar car - Don't do it without having a long discussion with a professional expert.  Your car is not like mine. You don't use it like I do. So many forum posts on the interblag  read something like - "Hey I installed this part and you should too it is really great and I got 5 more HP!"

A summary of what was ordered:

K-Member Package, 1996-04 Mustang, Forward-Offset Arms

MMKMP-31     $1,897.64
Springs 200lbs/in x 12" x 2.50
Sway Bar Bushings 1-3/8"   9-5168G

Rear Sway Bar
Weld IN  -  1-1/4" x .095" wall
MMRSB-8.1     $449.97
Pinion Snubber, Urethane, 1979-2004 solid axle

MMPS          $9.95
Total $2357.56

I will start work in a couple of weeks. It will be very interesting to see what this does!

Thanks for all the info. I agree with the binding issues with 4 links, and the solution of using softer bushings. A lot of GM cars with triangulated 4 link rears run into the same issues if you switch to all poly bushings. They say to use stock type rubber bushings on the uppers to avoid bind.

Since you have a panhard bar already, is there any room to mount a centered 3rd link and remote the 2 uppers? They make clamp-on 3rd link mounts that attach to the tube right next to the center housing. Not perfectly centered, but close enough to eliminate bind. The problem is usually the chassis side mount, which will be somewhere in the trans tunnel rear seat area. 

In reply to maschinenbau :

Thanks maschinenbau. Yes, I believe I have seen some third link on top designs out there. I am not sure if they would be better than a torque arm or not (basically the same thing but on top). Since I am also moving to a rear seat delete this winter that would make room to build a new torque box/hard point where the seat was. I am not sure what direction I may go when I turn my attention to the rear suspension again. This project is concentrating on the front but the rear  "came along for the ride". I have already dramatically improved my rear suspension over stock but it is still far from perfect.

There are so many choices when you get into it and it is very complex. I will be studying this. I have to be careful in that so much of the information on the webbernet is related to the science of drag racing (and I do mean science). That said, there is some incredibly useful information that can be had from the drag racing community. For example, check out    http://www.shopeshop.org/contentsDrag.htm The writer is a charter member of the original Ramchargers team. His insight on vehicle dynamics is applicable  to angle winders also.  

I could go with a top mount third link as you suggest. I could go with a torque arm. I could just refine the five link system I have now. First I want to chart out  my instant center, center of gravity and so on. I will need some scales to do that. That will likely have to wait for another year. 

Love the thread! Really glad I stumbled across this build. I too have a 2002 V6 Mustang. It's been my daily soldier since '09. Won't be much longer, time to get the wife a new ride and her '08 Focus will be my new daily. Then the Mustang will be a real project car. I have a few minor mods installed, and few others waiting to go on (living in an apartment complex sucks sometimes). Eventually I have big plans for her but no rush, family life takes precedence and I've waited this long already. It has given me time to research the heck out of it though, and learn more and more about the engineering/science behind performance cars every year. I've participated in exactly 1 autocross event so far, I hope to start doing it regularly soon. I'm lucky enough to live about 10 minutes from the only autocross club in over a hundred miles. I'm terrified of permanently twisting my chassis since I haven't yet welded subframe connectors in. My favorite part of your build so far is your rear suspension setup. I've had the thought for a long time of creating a poor mans 5-link by using Steedas upper control arms with a Maximum Motorsports panhard bar. I've even talked directly to MM about the idea and they said they see no problems with the concept. Steeda doesn't advertise the upper links for sale seperately, but I've seen them for sale on eBay for $400 before new in box. Sounds steep but its still a 5-link with slightly less adjustability for around $800 instead of $1300. Until now, I've never seen the idea utilized on any car. And you even took it a step further by designing your own upper arms which is awesome. Love the creativity and practicality of this build. Keep us updated throughout the off season.

In reply to The_Red_Stig :

Hi Red Stig,

Thank you for your kind words on my build log here. I have tried to make it something more than just a listing of stuff bolted to the car and explain why I have done these things (for better or worse). I also have taken my time, done research and let the car speak to me in its own language. It takes years to learn that language and I still have a long, long way to go. So much to learn still...

You are right: Family first.  I did not discover autocrossing until the kids had grown and left. I wish I had known about it when I had that red ’87 Golf GT so many years ago. That car was a blast to drive. But, back then, there was not enough time or money for such things as hobbies, so hang in there. You have your priorities straight and I can tell you, there is life after the kids have grown. And it’s pretty good.

When we lived in Michigan I was also near a small SCCA club that ran at three different venues within a half hour from home. They also had some real ringers in the club to learn from. Some multiple time national champs and several others that routinely placed in the top 10 or so. You can learn a lot riding with someone like that or having them ride with you. When you get going on it, volunteer to help set up courses (you learn a lot by helping set the thing up), timing and scoring, interface with the venue owner, find new venues, etc. It is great experience and not just from an autocross standpoint. Learn how to design a course (It is a lot harder than most people think to make a fun, safe course).

The Steeda upper control arm towers and the MM Panhard: Not enough clearance unless you change something up.

Look closely at the Steeda Links and note how far back the towers lean. The engineer who designed it needed to get the Instant Center to a certain spot to try and control lift/squat on launch. They  also needed to keep the arms as long as possible to minimize the geometry change when the car healed over or hit a bump. They also needed to fit it in the space provided above and attach to the original torque boxes (the hard points where the upper arms attach to the body). Compromises all around but they did pretty damn good working within all those constraints.  

A NASCAR has a similar arrangement except the upper arms attach in the middle of where the rear seat should be and therefore has much better geometry.

The Steeda Watts Link was designed to allow clearance for those rear leaning upper towers. The MM Pan hard was not. If you combine the two they will hit (it is really tight up under there). Also, if you rotate the Steeda towers up to clear the pan hard frame they will hit the underside of the car.

That is why my design has short vertical towers and shorter arms. The drawback is that my geometry is much worse that the Steeda design. My Instant Center is such that the car lifts slightly on launch. That is a penalty I am willing to live with for now for a more freed up suspension.

Twisting the chassis: I think that is primarily a drag car issue. You put a 600 HP Coyote in that thing with a drive train that can handle it and drag radials on a sticky strip and the car will turn into a pretzel without serious reinforcement.  But with the 210 Ft-Lbs or so of torque you have now that is not going to happen.

That said, autocross is hard on the unit body structure. You can actually hear the difference. Before the sub-frame connectors Mistress would groan and creak with each turn. Afterwords it was much quieter and more stable. I would put sub-frames on the list but unless you are running at a very rough site you could put them off a season or two. When you do – Full length weld-ins, any brand, are the way to go.

Here are my thoughts  - for what is is worth (if anything at all): Since you have other, better, priorities in life I suggest keeping the expenses to a minimum. As I have said many times, the slowest thing in the car is you. Go to events. Drive the car. Practice and have a blast doing it. Get a good set of tires (BFG Rivals or Bridgestone RE71R or Nitto NT05) on the stock rims (they are actually pretty light and quite strong).Then get a harness (it is hard to drive when you are hanging on for dear life). Get a data logger (I use Solo Storm in my phone). Study the videos and the charts after each event. Study them again in the off season. Then close up the differential with a T-Lock or Tru-Trac. Then add sub-frames (they don’t cost much) and stop about there. I would not even think about the rear suspension geometry until you are a few years into it. Consider this you learner car and have a hell of a good time on a tight budget. 

If you are determined to stay with the V6 SN95 for the long run note that there is a certain stubborn madness required. You will spend more money than most just catching up the HP.  More modern cars are much better right out of the box. People will show up that have spent $50k on their trailer queen. They will all look at you sidewise, scratch their heads and then about ½ of them will beat you. But the other half wont.  And they will all wonder how you did that with that 3200# grocery getter.

Thanks for the help with the rear suspension, you probably saved me a lot of future frustration. I'm unsure what level of performance I will eventually take my car to, but I always thought if I keep it long enough I want it to be a competitive autocrosser and a car I feel comfortable open tracking (so good brakes and basic safety equipment at a minimum). I thought if I wanted the most out of it I'd eventually convert to an 8.8 rear end and torque arm set up, or swap in a Cobra IRS. I kind of want to utilize the factory components in the car first, before swapping to more popular combinations. So I want to see how much potential the 7.5 rear end has before upgrading to a torque arm or IRS. Same goes with the engine, I'd like to get the most out of the 3.8/4.2 power plants, before considering an engine swap. I always thought a good level of performance would be in the 250-300 whp range, which these engines are plenty capable of. If I did ever do a swap, I think it would be coyote based or nothing. I know people say once you get used to a certain power level, you'll always want more, but for me, this about practicality. That's why I'm undecided or unsure on so many things, I've done the research, but you never know what the future holds so trying to plans years in advance is pointless to me. I also know the build as you go approach may very well cost more in the long run as you may end up replacing previously modified or upgraded parts, but that doesn't matter to me. For me, this hobby is about fun, I'm obsessive sometimes in my quest for more knowledge and dissecting technical data to the best of my abilities, but working on and learning about the cars is almost as much fun as driving them to me and a huge part of the entire experience, even if I make some mistakes along the way. I always want the car to remain very streetable, no matter how involved or serious I get with my motorsports endeavours, as 90% of the time I will enjoy it on the street, driving to and from shows or tracks, running errands on nice days or even the occasional road trip (better get some nice comfy Recaros or Corbeaus huh). This may seem foolish to you and hopefully I don't regret it, but I also don't plan to follow any rule books with my build and just modify the car as I see fit in a way that will increase my enjoyment the most. Then when I show up to events, I'll just race in whatever class they put me and ill do my best. My only real goal at the moment is to have as much fun as I can and bond with other passionate car guys and learn as much as possible in the process. Of course, when you get on track and the competitive juices start flowing my priorities may change, but as long as I'm not getting obliterated every time out, I think my ego can handle it haha.

What are your thoughts on the importance of brakes for autocross? The runs are so short that brake fade probably isn't a big factor right? Factory rotors and calipers with dual purpose street/track pads like Hawk HPS, SS braided lines and a good brake fluid enough? Cooling ducts necessary or beneficial at these speeds? Or is money better spent on good tires? Thanks for the help, and if I need to keep the posts more brief let me know, I'm not trying to hi-jack the thread, just excited to have a chance to pick your brain. My current setup is Bridestone RE760 Sports on factory wheels and studded snow tires on their own set of rims in the winter :). Which brings me to one more question. I know the benefit of good tires, but do you have any experience with lightweight wheels (the Enkei RPF1's for example), and is that a worthwhile investment early on?

Mr. Red Stig,

Oh yea you got the bug. You mention you don’t know what the future holds and what path you might take. Yes it is best to keep an open mind. An article in Sports Car Magazine recently asked readers to reflect at where they were and if they were stuck in a rut or not. Basically it asked: “Why are you still driving that car?” & “Why are you still racing in that class?” “Try something new.”  

To that end, a good friend of mine (Jay Payne) started out autocrossing in another ’01 or ’02 V6 Mustang. I helped get him started. He made some basic mods (tires/brakes) in the first couple of seasons but realized after driving my more modified car at a T&T he would have difficulty catching me with his car and even more difficulty being truly competitive.  So he leap frogged me and bought an ’02 GT. He has modified that car to the point it only travels on a trailer. I can only catch him now if he is having an off day and that is not often. Jay decided he did not like the beat he was dancing to so he changed the tune. He feeds on the camaraderie of the sport just as we all do but he also likes to win and wanted very much to place higher at events. He is a competitive guy (I love ‘em) and he realized he could not get what he wanted with that car. Jay also drives cross country truck and does not have as much down time as I do to putter with the thing all winter. I think he made a very good choice… for him.

I am still driving that car because for me the challenge is to make my car as competitive as Jay's (I’m coming for ‘ya Jay!) which would also make it very competitive overall. Jay is a good driver, very smooth. He may easily be better than me and he has had a lot of practice lately. However, I have reviewed his data logs online (and many others) and noted that his car typically corners at 1.0 to 1.1 Gs same as mine. Yet he is on RE71Rs on 11” wide by 18” rims to my 9” by 17” with the same tires. Also, his suspension is currently more aggressive (stiffer) than mine. Why do these similarly modified cars corner at the same rate? Well the 200 treadware tires are great equalizers. But Jay’s car should corner noticeably harder with his set up and tires (assuming our data logger equipment is accurate (big assumption)).  I think it may be that my car is lighter by roughly 165# or so. The 7.5 diff is 50# lighter and the rest is in the engine and other minor changes.

I have made all the reasonable mods to my engine (to the tune of roughly $4k) just to get in the ballpark of Jay’s 2 valve 4.6. I have no hope of catching him until I up the anti with the supercharger and new block. For the time being I have reached diminishing returns on power. That is a primary driver why I am going after the suspension again and jumping to a new K-member. If I can get my typical corners up to 1.1 to 1.2 Gs…

So – Brakes. These cars have pretty good brakes from the factory. For your skill level I absolutely do not recommend changing them yet. Three reasons: 1 –Remember my “Rule of Dave” from earlier posts. The 3 or 4 tenths of a second you MIGHT gain with better brakes will be grossly offset you the 2 to 4 whole seconds you waste on course with bad driving. Been there, done that (poorly). 2- You will not understand/appreciate the better brakes until you have autocrossed on the current brakes with the Autozone pads in them. 3- With the current tires and set up, it may make absolutely zero difference in your times.  

Question: On course, can you lock up all four wheels? Do the antilocks come on front and back? If the answer is yes then you do not need better brakes at this time for the tires you have. If the answer is no then either you need better brakes OR you are not pressing the pedal hard enough (A very, very, very common novice mistake). You need more seat time while paying attention to this little detail to determine if a brake upgrade is a good investment or a waste of resources.

If the answer to the question above was YES and you then put some stickier tires on her then it may easily switch to NO. One change to the car combined with more driving experience leads to another required change.  But that second change is only required at that point in time. Sooner is a waste and could even be detrimental.

I am currently running on stock brakes with HPS pads. These have served me well until the last two seasons (I’ll get into what has changed below). I recommend speed bleeders (speedbleeder.com) for ease of maintenance. I also put on Russell SS hoses and use DOT4 fluid. I only cooked the brakes once when I was learning to drive two foot and was inadvertently riding the brakes. That was a little scary and my hands were shaking when I came off course. That is when I added the bleeders, hoses and fluid and a lot more practice.

Normally in an autocross the front brakes run in the 800 DegF range.  Standard OEM equipment can handle this easily if it has been maintained. In the incident above I had not bled the brakes for years and the fluid was many years old.  Bleed your brakes every season. Change out the fluid every two seasons or so – it is hygroscopic and collects water. Water boils at low temperatures.  Be careful not to get air down to the antilock module or you will have to take it to a shop to get it out (can’t do it at home without flush equipment).

Brake ducts would only be useful on road track cars where the braking is much harder and much more sustained. Temperatures for road track can easily get up to 1100 to 1300 DegF or more. 1100 DegF is a dull red glow. Most OEM equipment and some upgraded equipment cannot handle that unless it is a very high performance car. For an occasional Track Night In America you would be fine because you are not actually racing and won’t push it so hard because you do not want to wreck.

What is wrong with my brakes now? What changed? Last year I put in a high lift cam. Something they don’t talk about much is that aggressive cams typically lower the manifold vacuum. My car uses that vacuum for the power brakes and now there is less of it. I noticed this last year as it took all the force I could muster to stop the car on course. Regular driving was fine. After inspecting/bleeding the brakes and finding no problems I did some research and found out what was happening. I have been researching putting in a vacuum pump. Also, Hawk has come out with some more aggressive Street & Strip pads. I might try them, however: 1 – They are very dusty & 2- I already bent my caliper brackets once a few years ago. It is an easy repair but even more aggressive pads might do it again. Still thinking…

Tires: Keep your RE760s until they wear out. Then upgrade to RE71Rs or Rivals. The NITTO NT05s I mentioned earlier are not as fast as the other tires but they give way gradually, last well and are typically a little cheaper. I ran on them for a couple of seasons. The reason to keep the existing tires are the same as the brakes: They are good tires and will serve well for now. With more seat time you will be able to feel, understand the difference. When you change them they may lead to other things (brakes perhaps?) Let the car tell you what it needs and then research the specific solution.

Wheels:  The 16 x 7.5 OEM wheels on your car weigh about 17.55#. That is not bad and you have to spend a fortune to get some Forgelines down in that range. They are also pretty strong (Ford does not like lawsuits). I don’t think I replaced my wheels until my fourth year and I went with some 17” x 9” Cobra knock offs from StangMods. They look nice. They are heavier than the OEMs. I had to replace one because the rim got dinged and then cracked. I don’t recommend replacing the wheels for a few seasons. There is a lot of other lower hanging fruit. You will know when it is time and you will save money on tires in the mean time. I think most people on forums bragging that they got some Forgeline or Enki wheels are bragging more about their pocket books than the wisdom of their purchase. There is a place in the world for those wheels but I do not believe my car is ready for them yet. That said, I will be giving my wheels a close inspection for cracks or signs of distress over the winter.

Something I plan to post this winter is post my spread sheet tracking all the mods made to Mistress, costs and recommendations if they were actually useful or not. I have to get that updated and cleaned up.

I don't think my car is equipped with abs. During my autocross session I don't remember locking up the tires at any point, I likely wasn't braking hard enough like you said. On my last few runs when I was pushing harder, it induced a little understeer and the tires started screaming at me. So either they weren't at optimal temperature or reaching their limits in cornering at least up front. On my first few runs I tried to focus on being smooth and progressively got more agrresive where I thought I could make up time. The good news was I improved every run, however all that tire squealing only took off a few tenths compared to my best lap without tire squeal, and it felt like I was pushing much harder and more violent if that makes sense. I think I took off a little over 2 seconds between my first run and last run if I remember right, didn't knock over any cones on any runs. 

Also, as I'm sure you know, '99-'04 V6 stangs are the only SN95 cars that Ford decided didn't need rear sway bars. Do you think adding a GT rear sway bar or matched front and rear aftermarket bars would be wise early on? My thinking is that it may help fight the understeer and help the car rotate through corners more. Also, I always thought an adjustable rear sway bar would be nice for changing weather conditions etc..., but do you think it would over complicate things?

That solo storm data logging software looks very interesting. It allows you to sync video and data right?

I have a 97 V^ Mustang that I autocrossed.  I added a rear sway bar from a Mustang GT and it helped the car turn in better.  A very noticeable difference.    Try to find a junk yard one before you go the expense of an aftermarket adjustable one.  Mine bolted right in.

Have you ever considered converting to a manual transmission?  I think it would help with acceleration off the line and off corners.

Reply to Red Stig and Mustang 50:

If your car has ABS the control module will be in the front of the engine compartment behind the radiator just to the passenger side of the coolant overflow tank. It is about 6” square. I always thought that was a weird place for it.

Yes it is likely you were not braking hard enough. I often find myself under braking when I am not on my game. Or you don’t have it. ABS is a nice learning tool because you can feel when you are breaking at the tires limit. Many drivers poo-poo ABS because threshold breaking (where the tire slips only slightly) is more efficient (but only a little).

However, threshold breaking is very hard to do consistently especially on the uneven terrain of a parking lot for 1.5 seconds. On a road track, with more consistent traction (in any given corner) and more sustained breaking a driver can get a much better feel for where the limit of the tires are. In autocross it is over just as you found it. I like ABS. But if you don’t have it, I would not bother installing it. I don’t like it that much.

Improving on each run is great! It can be hard to do sometimes. Lately my 3rd or 4th run out of six is often my best and I can’t catch it again on the last runs.

No Rear Sway Bars on the V6:  An obvious reason is to save money. But I think Ford's decision was also based on assumptions about the driving skills of the typical V6 Mustang owner. Understeer is the accepted norm in the U.S.  When the car doesn't seem to be going where the driver wants it to go, he just brakes and turns the steering wheel farther – an intuitive design considered defensible in court.

You have to be careful just adding a rear sway bar to your car. See my somewhat hilarious, somewhat terrifying story on page 1 of this blog. Oversteer is a bit scary and happens very quickly if the suspension is not balance properly.

The ’97 V6 Mustang probably has a 1.06” dia front and no rear. The GT that same year had a 1.18” Front and a 0.94 rear. If you put a rear sway bar from a ’97 GT on your ’97 V6 you will have slightly more oversteer than the GT (all other things equal which they are not – The GTs are sprung differently).

The 2002 V6 should have a 1.00” front and no rear. The GT probably had a 1.04 Front and a 0.905 rear. Same potential issue.

As I write this and look at the numbers for both cars these are really pretty minor differences compared to the GT.  The GTs being American cars are also probably designed for a little understeer.

So to end of this discussion – Mustang 50’s suggestion of just pulling a rear bar off of a similar GT is probably pretty sound. All I am really saying is – Be careful. This will make a big change and you do not want to discover the extent of that change on a wet curve and go ass-end into the trees.