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Asphalt_Gundam
Asphalt_Gundam Reader
3/23/22 10:08 a.m.

In reply to OneSickGNX :

Torque Arm is not off the table but I've been following the developments that Lance is doing on his Monte with this 3 link kit here My 1985 Monte Carlo SS Barney... - Page 35 (pro-touring.com) (about half way down the page)

He seems to believe its a solid upgrade and giving some factor for a few other changes he did it seems his whole setup is over a second quicker in an autocross. I have no reservations about cutting metal so I'm thinking I will shoot for a longer 3rd link than his setup. I could run it forward enough to tie into the main hoop some how. I've also spent time eyeing up some of the modified oval track 3rd links. The spring types for dirt would be too much travel but some are tuned with poly bushings and might keep things more in check. The possibility of having torque absorption device for transition to throttle and brakes to keep the tires hooked up is appealing so long as it can be accomplished without major movement and potential tire to body contact.

I've yet to seriously look at the car in the back and visualize anything out. 

Asphalt_Gundam
Asphalt_Gundam Reader
3/23/22 10:26 a.m.

Regardless of what setup I go with the stock lower control arms will stay unless some crazy long upper can used. I've researched enough to know that drastically different length upper vs lower makes for weird movements during travel. STD lowers are a little over 19" with around 17-18 effective (parallel to car distance) but the STD 4 link upper is only about 10-11" with under 8" effective. The shortest push/pull links are 16-18" w/o heims so that would be a good length but the chassis and body will need cutting plus a mount off the main hoop.

If going torque arm I'd just need to fab the mounts and arm itself. This makes for a nice long lever for increasing load on the rear tires. What I loose is rear steer and gain possible bind issues that I've yet to think how to eliminate. But honestly don't know if it is even worth considering that possibility. My current rear steer has been great of rotation during autocross but also (I realized too late in the year) that it was likely hurting drive off corner on the road course. So maybe eliminating it would be beneficial in the long run.

Regardless of which I plan to do an adjustable height, axle mounted pivot for a watts link vs a panhard bar. I may even attempt to be able to run and test both setups for back to back testing if I get that far or have doubts about either. This is largely uncharted territory for a G body.

OneSickGNX
OneSickGNX Reader
3/25/22 9:45 a.m.

I could definitely see binding with a torque arm but packaging is a lot nicer, especially once you start chasing correct upper link lengths. Maybe solid but adjustable mounting the axle side of a torque arm and using a big single hiem joint at the forward mount and double hiem jointed lower arms. I would imagine it would kill ride quality though. Speaking of which how did you like the solid bushing front control arms?

Asphalt_Gundam
Asphalt_Gundam Reader
3/25/22 2:55 p.m.

In reply to OneSickGNX :

Torque arm is easily more package able. I think the problem comes in if trying to run anything but level lower control arms (to induce rear steer). Even with a heim at the front of the TA the axle is trying to rotate at the differential or at least that's what making sense to me. I could see a wishbone torque arm with the heim at the axle as a solution. But where is the actual rotation taking place? Axle side of lower control arms, the chassis side, or somewhere else? For a handling application I feel like there are many compromises vs even an ok 3 link. Really, the triangulated 4 link works decent but there's plenty of it's own compromises.

The solid bushings, or delrin like my fabricated arms were a big bump in getting consistent alignment in the front end. I had started with poly but after 2 years they were blown out...like 1/8"+ slop. I can only imagine how much it was all moving around on track. At this point the front lowers are delrin, uppers are ball bearing, rear upper and lowers are Ridetech's spherical bearings and I can't say I've really noticed any change in the ride quality. A little more noise from it but hardly something I'd call rough ride. When I went from the stock 450lb/in stock springs to 900lb/in and was a little rougher ride but still acceptable for street duty. 

Asphalt_Gundam
Asphalt_Gundam Reader
4/19/22 12:44 p.m.

Took a break from working on the car after getting the suspension parts out and ready to powder coat.

Got back to it last week and have been trying to knock out anything that'll hold me up for getting some testing in.

For starters the Viking coilovers arrived and I assembled them.

In an effort to get more Ackerman out of the car I modified the steering arms. Cut them to eliminate the step the at was intended for a caliper bracket with moves them outboard about 5/16". Some clearancing of the arm/spindle was required but not much.

I then worked out what I wanted to do to improve the expansion tank function in the cooling system. Before it just wouldn't drain to the radiator as intended to keep it full. It would stay in the tank instead. So this time I mounted it closer to the radiator and will be adding a line directly from the radiator to the tank then back to the pump. Heater core outlet will go to the tank as well. Since I've rarely had fluid go into the overflow catch I fabricated a much smaller tank for that and integrated it to the expansion tank for minimal weight, hose, and space saving.

Reinforced the radiator mounts too as they deflected the first time the engine warmed up.

Since I had a tight spot in the steering I was concerned that it was due to u-joint angle and didn't want to risk something becoming a lock on or off track. I moved the rack forward 1-1/4" and it cut the u-joint angles in half. To get the tierods back to a desirable position I disassembled the rack and modified it by welding on relocation tabs/arms. Now the tierods are 3/4" farther rearward than before for even more Ackerman geometry.

Suspension parts came back from powder coat Sunday so final assembly of the front has begun.

Asphalt_Gundam
Asphalt_Gundam Reader
5/9/22 11:40 a.m.

Haven't posted in a few weeks. Feels like spring time projects are getting in the way most days. But progress is being made regardless.

For starters I finished modifying the rack after relocating it forward and now the tierods are farther rearward than before. I figured welding would be stronger than a bolt on option. The backfire was I didn't think about boot installation. I just cut them length wise to install and have a few zip ties keeping them mostly closed. It's kinda hack but into this rack and pinion for pretty cheap so it worth a try for now.

I then worked on final assembly of the front suspension. New bolts and lock nuts everywhere and cycle everything check for any clearance problems. Only item of concern is upper A arm to coil spring at/near full compression. Left it for now but may need to do something about it later if the suspension every comes close to that much compression travel.

Also I now have a small sponsorship from Viking Performance! I was absolutely blown away how good the shocks were with the old setup and I can't wait to try out a coilover package with all the changes I'm doing. 

 

 

Asphalt_Gundam
Asphalt_Gundam Reader
5/9/22 11:49 a.m.

Up next I was working on my cooling system changes and realized the water pump gasket was leaking. I needed to order some fittings anyway so it was a good time to fix the leak and drill/tap the heater return for an npt/AN fitting.

I pulled the front clip again to get paint on the stuff I skipped before the car show. The extra room made figuring out a new power steering line and cooler setup much easier. I was thinking I'd mount the cooler ahead of the radiator again but I would have needed to order more line which isn't cheap. Plus no matter what I tried to think of for mounts and line routing would have put holes in the radiator ducting that wouldn't be easily sealed again. Decided on mounting the cooler low to get air from under the car and the location was workable with the line and fittings I had on hand.

 

 

Asphalt_Gundam
Asphalt_Gundam Reader
5/9/22 12:28 p.m.

At this point I wanted to get the splitter fit better. Had torn off the diffusers last year and wanted to make some bigger ones anyway. Added a large center one both for down force gain (hopefully) and to guide air to the power steering cooler. Welded some nuts to the chassis brackets to make removing the quick release easier if needed.

Didn't take pic of the process but I fabricated the diffusers from some sheet aluminum I have. I think they came out ok.

Once the front clip was back on I started on the radiator ducting. Almost forgot to make upper plates before installing the bottom and making installation of the tops impossible. Most of the ducting is made from sign aluminum. Stiff but bends and holds shape really well while still being able to flex and return to position. I shouldn't have to worry about hitting it on the ground or trailer and having it get trashed.

With such a large opening scoop to the front I should be able to tune any additional cooling needs by cutting away some bumper or splitter air dam or if less is needed tape up the grill.

I am a little disappointed in how the radiator fit came out. It's more difficult to remove with the ducting the way it is. But doing something different would be a lot of work just for a convenience. I don't anticipate I'll need to remove the radiator much. Could always pull it with the front clip anyway if needed.

 

Asphalt_Gundam
Asphalt_Gundam Reader
5/9/22 12:56 p.m.

Now that the radiator was final installed I could finish out the cooling system. Goal was to have a functional expansion tank that would keep the radiator full at all times vs the sorta but not really setup last year. 

Previously I had the tank inline with the heater core and water pump which was the easiest way to hook it up and have it be the high point.

This time around I moved the tank forward and mounted it vertical as high as I could. It gets coolant from the heater core and radiator outlet now before going to the water pump. 

As you can see in the pictures above I fabricated a little overflow tank and integrated it to the expansion tank. Makes for a nice compact package vs a remote tank like before.

Asphalt_Gundam
Asphalt_Gundam Reader
5/9/22 1:55 p.m.

Getting caught up to last weends work I finally was able to get the bumpsteer gauge out again and try to dial in the tierod heights. It took some back and forth but in the end I was able to achieve .015 for 3" of travel on both sides of the car. Passenger side is consistent for nearly 4" but the driver's starts to change more after 2" compression or 1" droop. Considering the best I could get on the old setup was 1/16th (.062) I call this a big win.

Then the car was ready to get on the ground and double check ride height before finalizing the alignment. Only needed to tighten the lock nuts for the coilovers. Make a small caster adjustment to the passenger side and set the toe.

I also needed to fix a few little things like the battery hold down, add a ground wire, and fix the kinked return fuel line.

Then it was ready for a test drive!

Started out letting it get warmed up and checking for leaks before going anywhere. That all looked good so I headed down the road. I was most concerned about the steering so was keeping it slow and moving the wheel back and forth to get a feel for the power steering assist level (it was working so that's good). Once I felt out the brakes and saw that temps were staying in check I headed a few miles out to a stretch of road where there aren't any houses, it's wide and straight with wide ditches so if something went sideways it's as safe as possible. Was able to see coolant temp never got above 169 (thermostat is 180). Putting fast steering inputs into the car back and forth was smooth and responsive with barely any body roll thanks to that splined sway bar. Shock were still full soft still. What I did find was the brakes while working well, pulled to the right.

Once back home in the garage I confirmed a leaky caliper seal as the culprit. Also noticed that the steering u joint just rubs the header when turning right so that will need clearancing. No leaks after test drive but the lower radiator hose had a drip after sitting overnight. Second clamp and tighten the others took care of that.

I pulled the front calipers off as I had a set of seals to swap them out. I need to change to fresh high temp fluid anyway still. Then Sunday I finished draining the brake system and rerouted the front brake lines. While setting the steering stops the day before I found out that the tire would hit the brake line tab before the swaybar arm and limited my available turning radius. I'm glad I bothered to check clearance at the back and saw this. 

Since I had the brakes on my mind and have been putting it off I started figuring out a solution for brake cooling ducts. Plan is to integrate the inlet into the radiator duct in the mostly facing forward area, run hose straight back into a 45 of tube that angles through the frame opening and another block off plate to get a straight shot at the spindle where the tire won't contact it at full lock. I haven't had a need for anything fancy here yet but would rather have a supply of at least some air to the rotor just in case. Everything will be chassis mounted so no interference or messing around when removing or installing the splitter. Speaking of which I made some release cables the other day out of a bicycle shift cable, nothing impressive but it works. 

Gave up on fabricating a complex frame pass through section and just ordered some 45 bends for that location. Then switched to making the spindle mounted parts. Again they're super simple and should do the job.

 

 

tperkins
tperkins Reader
5/9/22 5:59 p.m.

You are crushing work on this thing. 

Asphalt_Gundam
Asphalt_Gundam Reader
5/16/22 12:49 p.m.

I've been able to get out and test drive the car. Went on around a 30 mile drive least week and other than some tuning needing to be addressed the car drove well. Stopped for ice cream to prove it's still a street mod class legal car. With the temperature around 75 it barely went over 170 cruising with the cooling system changes.

I had also swapped out exh gaskets to remflex after pulling the driver's side header to take care of the steering shaft rub.

Then while the garage was open I took care of oil changes and maintenance on the daily and more importantly my truck so it'll be ready to tow to Blackhawk this week. Noticed a rub on the lower radiator hose that could have been bad news and re secured it away from the steering link.

Once the Cutlass was back in the shop I needed to get the accusump hooked back up. I wasn't happy with the way I routed the hose last year and tried to find a better solution. After a lot of trial and error fits I figured out a route that gives way more clearance to the header, not touching the bell housing and keeps the line tucked up to the floor. Plus I could install the line before the sandwich plate went on so it's actually tight. Track side install last year was lots of not getting things ideally tight and compromise on routing.

Thursday night the new coilovers for the rear showed up! Viking Crusader double adjustable with "GP" valving to match the front. I went with a 250lbs spring as a starter with 300lbs as spares for possible need once aero and going 3 link come into play. 

They installed right in place of the old shocked without any extra work. When I did all the chassis stiffening I had plated and braced the upper mount and the lowers I fabricated for the 9" so they're plenty strong to handle the spring loads already.

With the major chassis changes over the winter I reset the rear control arms to as close to level as I could. This is the uppers in the 2" raised chassis side I made last year and the lowers at the 1-3/4" drop hole on the axle side. Lowers are still slightly up to the front. Uppers look very close to level. This should be a pretty neutral rear steer position to baseline from.

Saturday I was able to go test at Black River Motorsports Park ( which finally got their land use permit last week and can now hold events). I was sharing the afternoon with a couple drift cars which worked out to take turns as I spent several outings just getting the brakes figured out. I've only had a couple sessions at Road America on these Hawk dct60 pads and it took some figuring out. I'm not particularly impressed with them. They're weak and horrible pedal feel until up to temp then they were so aggressive that I had near immediate lock up. Had to make a massive bias adjustment just to get the tears working on par and minimize lock up. The Wilwood BP-30 was a way more friction linear compound and easier to modulate. Backordered until next year where I've looked despite online claims of in stock or only a couple weeks out...

I was also figuring out what shock settings to have as my baseline. I was paying close attention to the travel and increasing resistance until the compression under cornering and slalom was about an inch from the bumpstop front and rear. At this point the car would push/understeer past a certain steering input or on transition. Increasing the rear stiffness reduces the push back to a neutral handling car. Ended the day with a decent baseline and plenty of room for shock adjustments further. 

Before going home I had a short list of small thing that needed addressing. Some bolt were working loose, as the suspension settled I had to adjust the ride height a little and I gained significant toe out somewhere along the lines. Fixed all this on Sunday morning.

Overall first impression is that I'm happy I didn't create myself a basket case. The splined swaybar setup keeps the car very flat in turns, the new suspension geometry seems to be less upset by movement near the limits and the softer sprung coilovers are handling rough surfaces and bumps much better. The steering is quick and predictable with a little more effort needed than before. But there is some slop at center and one side of the cylinder is leaking a little (used rack after all, but it's completely rebuild able). With the slightly faster ratio getting my arms crossed up finds a point where it it too much steering angle to maintain grip but shock adjustments were helping with that. The rear now hooks up really well. I can tell the car is lacking rotation from the significant rear steer before but there's so much more drive off corner. This may or may not help in autocross situations but should be better on the road course.

Testing was on last year's end but of season tires and without aero.  I'm attempting to get the mechanical grip sorted before aero and new sticky tires. I intend to bring the tires to Blackhawk but not the aero. Probably swap tires at some point during the weekend and get a scrub session on them, then feel out the difference before Midwest Fest in a few weeks.

AngryCorvair (Forum Supporter)
AngryCorvair (Forum Supporter) MegaDork
5/16/22 1:06 p.m.

your expansion tank's got an expansion tank.  that's baller!

Asphalt_Gundam
Asphalt_Gundam Reader
5/16/22 2:09 p.m.

In reply to AngryCorvair (Forum Supporter) :

Yeah, for the inevitable time when its bound to get hot and push some coolant out I'd rather it be in another tank vs all over the car/tire.

And I forgot to mention it above. When out testing I was able to flog the car pretty hard for several minutes and the coolant only ever got up to the low 190s. Last year I usually needed to stop and do several cool down laps because it was getting up past 210. Now it seems like I could lap all day if I wanted to and the engine not get hot.

Shavarsh
Shavarsh Reader
5/16/22 5:38 p.m.

Great explanation of your setup routine, I'm taking notes. Starting to get into the suspension tuning phase of my own project.

Asphalt_Gundam
Asphalt_Gundam Reader
5/23/22 11:33 a.m.

Back from GridLife Track Day Picnic at Blackhawk Farms and WOW! The car is freaking awesome!!!!

Got to grid first in line for first session (like last year). Took only a lap or two to get back in the rythm of the track and start picking up speed. A few laps later I start passing a few cars and things are great. Then right after getting a point by I brake for turn 7 and start my turn in, at which point I loose power steering and jump (launch more like) the curb. Kept it away from the wall but pulled off at the station worker stand and waited for the end of session. So now at the end of first session the car is broke (just like last year). After getting the car back to the pit on its own power it was obvious that I would never be able to drive it without the power steering, just way too heavy on the wheel. I start looking it over and all I did was toss the belt... except the alternator belt is missing too. A couple other drivers said they noticed a little smoke from my car and all I could find was some shinny rub on the PS pulley guide and some belt shavings/dust on the alternator housing. The water pump belt was present and accounted for but unhelpful in explaining what happened.

I still don't know what really happened. This drive system has been flawless and unchanged for 3 years so for it to suddenly have a belt rub/failure is odd. Both alternator and power steering pump are free spinning without anything to indicate they somehow caused it. No big deal as I've been hauling around spare belts to every event for 3 years. Except....I can't find them...my idiot self must have forgot them on the bench at home after I last minute had to unpack the electrical stuff to repair the trailer brake wiring. In an act of quick thinking (or desperation) I called some friends who were on their way down and detoured then to Pegasus to get parts. I hadn't even looked to see if they had parts yet but didn't want to have to back track my friends (turned out it was 10min detour tops). I check the Pegasus website and they don't have my style belts. But facing the alternative of a scrapped weekend I called and had them pull out the only belt of similar length and width, knowing that the pitch and drive tooth style were wrong. Nothing they had would work on my alternator so I resolved to just charging the battery via jumper cables off the truck between sessions if the belt for the power steering would even work. I missed a couple sessions but changed the PS drive gear alignment just a little on the mandrel just to center it up more. While the new belt that arrived was the right length and width, it was half the thickness and the drive teeth small. I wasn't real optimistic after testing it's engagement on the crank pulley. Having no other option I pulled the PS pump tight on the belt and bolted it down. I couldn't slip the belt by hand and a quick lap of the paddock had the power steering working. 

With enough confidence to try another go on track I went back out in the afternoon and the car kept going the entire session. I mentally kept my downshifts gentle since that would be the most likely time to slip the belt I think. In fact it was working so well that I was back up to pace by the end of the session. Upon inspection after coming in the belt showed a little bit of wear but seemed to be holding up just fine. Last session of the day I went out and knocked 1.6 seconds off my morning time.

Feeling good about the belt being able to hand in there, Dex helped me swap wheels and tires so I could scrub in the new RT660s in the morning. 

The pot luck dinner was great and my big bowl of grilled potatoes and carrots was decimated for the second year in a row. Reflecting I think this is one of if not my favorite event. It just has the feeling of friends, family, camping and oh look there's a race track too! The primary emphasis is on the people not the cars as it's a no competition points event. Last year Alayne said this is the event she'd like to bring her boys to out of all of them and this year we did. This was windfall itself. They made friends in about 30 seconds from getting out of the truck and spent more time outside playing in the dirt and woods than ever before. It was great to not have a screen anywhere near them all weekend.

Sunday morning I took it easy all session just to scrub the tires in and check pressure afterwards. Didn't bother making any shock adjustments beyond the previous day's which as just increased compression on the front to ease a twitchy on the brakes feel. Second session headed to grid I see Chris standing around holding a helmet and pull up next to him to see if he wants a ride. Which he gets excited and says "finally....only took 3 years" (every time he's asked in the past I've had some kind of issue going on that either had the car down, performance comprised, or I was running a competition group). We get released 4-5 cars back from the front and get in a few good laps before traffic becomes a consideration. Even with Chris in the passenger seat and a full tank of fuel we shave another 1.2 seconds off the previous day. There was red flag situation towards the end of the session and dirt kicked all over turn 3. No idea what I ran over but now the driver's rear is leaking. Ran the last morning session by airing up the tire right before going out and it held up without a problem. Actually went over pressure from heat. Andrew hopped in for that session and we ran similar lap times while having more traffic to negotiate. 

Packed up at lunch to make the long drive home and get the boys back at a reasonable time for school in the morning. Would have liked to run the afternoon sessions but not getting home at 1 am for work at 7 was nice too.

Overall I'm very excited for the season. Easily 400 percent happier than 2 weeks ago because for the first time the car is, in my opinion, properly fast. There is so much grip everywhere even without aero and it's actually hooking up on corner exit. While there is a list of things to complete before Midwest Fest in 2 weeks I have a level of anticipation that I haven't for a while.

Asphalt_Gundam
Asphalt_Gundam Reader
5/25/22 10:56 p.m.
Asphalt_Gundam
Asphalt_Gundam Reader
5/26/22 1:28 a.m.

Here's the video overview of the winter's changes.

 

Asphalt_Gundam
Asphalt_Gundam Reader
5/31/22 12:38 p.m.

Knocked out the final prep work for GridLife Midwest Fest over the weekend. Mostly just maintenance stuff on the chassis, getting new belts, and checking over the car. 

Then I had time to kill with the rainy and cloudy weather so it was as good a time as any to swap to the fiberglass hood. This is an older hood off my other car and it a little banged up and needed all the fasteners replaced. Took a while and had to do a little shifting of the holes to get everything to fit. Luckily the new stuff was larger so my non-consistent install from 2008 could be largely corrected. 

The hood installed I was then worried about not having vents for heat/pressure. After some deliberation I decided it wouldn't look completely stupid and re-used the vents off the steel hood. Put them on the cowl/raised section because the fit and this is best hot air exit right over the radiator. Eventually I want to seal off the air cleaner to a functional cowl induction and exit duct the radiator.

Overall the fiberglass hood is an estimate of 35lbs+ of weight savings.

I also finished up the brake ducts 

 

 

 

preach (dudeist priest)
preach (dudeist priest) Dork
5/31/22 4:31 p.m.
Asphalt_Gundam
Asphalt_Gundam Reader
6/6/22 1:38 p.m.

Home from GridLife Midwest Fest and what a weekend. Probably the most fun one yet. 

Started out the weekend with the same settings I ended Blackhawk with. Ran a PB followed by a shock adjustment and another PB on Thursday. Shock adjustment after that was worse so went back to previous for Friday morning plus a wing adjustment. Tire pressure adjustment for the 2nd session. That was better but didn't completely fix the problem so I tried a rear lower control arm angle change by going up one hole. It fixed the push problem but caused  a very loose rear which was immediately obvious that it was slower. So for Saturday morning I figured I'd go the other way just to see what happened. I knew I was adding rear steer back in but maybe it I got rotation done on entry I wouldn't be asking so much of the front end. Data at this point showed last fall had faster corner entry (with lots of rear steer) but this year's setup had higher min speed and better exit.

Saturday morning session I was up by over 1 second going into 7 but I missed 4th and go 2nd gear by going for the shift while the chassis was still loaded up in 8 preparing to transition to 9. Completely me doing a dumb thing by trying to do too much at once. Luckily I didn't damage anything and made 10a to escape off the hot track. Rejoined at the back and kept catching traffic for a couple laps and by then I'd over driven the tires too. But the car was handling great and I just needed to drive it without messing up. Only went a tenth or so faster early afternoon and was just preparing for evening session. 

Which turned out to be a cluster F... A couple cars had jumped me in the line and on the out lap someone was holding up the pace. And whoever it was really screwed everyone behind them. They finally get a move on on the back stretch but by now there's 2-3 cars right behind me we all try to set a gap but I was already compromised on turn 11 to start a hot lap. Not that it mattered by trun one I had caught the car in front of me. Who then decides to do a half hearted lap and not bother giving a point by. I get around them on the back stretch as they're still off pace and I bet there was 5+ cars in my mirror by that point. I get a good start on lap 2 and going into 1 I already see catching the next car before the lap is up. Frustrated at this point but I keep going and to my luck that next car I see spun off in 3 so I now have open track in front. The next lap I make a solid improvement but it wasn't a pleasant moment. I've not come off track this pissed off before. One or two people blew most of the session for over half the grid and this was after GridLife had tried to address people holding up out laps earlier in the day. Upon talking with timing and scoring they were equally upset about what happened. Was end of competition so nothing to be done anyway.

We got some open practice Sunday morning and I just went out to at least get another shot a lap or two. And ran back to back my fastest laps of the weekend 1:42.99 followed by a 1:42.88 on which I lost a few tenths going around another car and missed the apex in 10 and 11. I am thrilled with those laps and confident of the car's potential. 

Asphalt_Gundam
Asphalt_Gundam Reader
6/8/22 11:32 p.m.

Car was rock solid reliable all weekend long!

Off to BIR for Proving Grounds part 1 this weekend for Autocross, HPDE, and Tripple Track Shootout

 

Asphalt_Gundam
Asphalt_Gundam Reader
6/14/22 1:25 p.m.

Last weekend was MAP Proving Grounds at BIR. Once again I was signed up for Friday autocross, TTS, and HPDE.

Friday went well. Course flowed well and was only a little bumpy but surface was very dirty and thinking about the throttle make the rear step out. Made shock and tire pressure adjustments until I could at least put some throttle down. Ended up being more of a drift session than autocross. Still was able to drive to a 10th in class and 26 overall out of 129 which was 2sec off the fastest car with doors and 1.5sec from the class winner. An improvement over last year's best.

Saturday afternoon TTS kicked off with the drag strip passes. I ran out of time commit to setup testing for this and just took a guess at the shock settings and tire pressure. It was much better than last year only spinning some of first gear and actually hooking up in 2nd. Late year's best of 15.0 was turned into a 14.08, 14.03, and 13.98 for this year. I don't know where I placed but this ET last year would have been enough to bump me 2 spots overall at the end. 

As soon as drag was done I reset the shock and tire pressure to autocross settings from the day before and put the truck with the wing on. I figured any little rear grip bump would be worth it after how Friday went. The course was much tighter and way bumpier than the day before. So much so that I had problems with understeer and even in one spot bounceing so hard the car lost all grip. I pulled out several clicks of compression and rebound every run until the car ran the course without loosing grip over the bumps. At which point it was handling exactly how I like it. Jumped up several spots once I had it dialed in. Finished 6th in class and 22 overall out of 142 which was 1.9sec off the fastest car with doors and 1.27sec off the class winner.

At this point I'm was feeling really good about overall results as the road course/standing start was my strongest finish last year. 

Spent Sunday morning doing HPDE getting familiar with the track again and working up pace to going flat through turn 2 again. Then in session 3 after getting through T2 flat for the second time the brake pedal goes suddenly soft ... I have just enough room to keep it on the pavement around T3 but the brake pedal is nearly gone. Just a little bit at the very bottom.

I limp it back to the pits and don't immediately see any leaks under the car, resivour has fluid. Then I see this:

Evidence that the caliper bracket had been cracked for some time and the it tore apart the rest of the way and broke the caliper.

Luckily for me (extremely) that there was clearance between rotor/caliper/wheel so that it didn't lock up/destroy the wheel and this happened around 120mph.

I've clearly exceeded the expected forces of the dirt/circle track brackets intended use. I'll be making my own from much thicker plate this time around. Replacement parts are already on the way.

GCrites80s
GCrites80s Dork
6/14/22 3:42 p.m.

Now we think of circle track stuff as being pretty tough, but a lot of oval cars never see 120mph and while their brake applications are frequent they usually have short duration.

jfryjfry
jfryjfry SuperDork
6/15/22 6:51 a.m.

Woooow!  So glad that didn't go nearly as bad as it could have.  
 

love this car and reading about all you're doing with it 

 

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