Great thread, just opened it yesterday. I've been watching the prices drop on the SN95 Cobras. Can't afford to play, but I still find myself on CL regularly.
Looking forward to future posts.
Great thread, just opened it yesterday. I've been watching the prices drop on the SN95 Cobras. Can't afford to play, but I still find myself on CL regularly.
Looking forward to future posts.
Well this kept happening:
Which prevented a lot of work from getting done. I did manage to make one change, can you spot it?
Here's a close-up if you haven't figured it out yet:
Once the snow melted for the 5th and final time, I got to work under the hood:
How did this get so dirty?!?
Yes, that is a BAND-AID used as a way to keep the wires together for the dumb splice! I finally ripped out those terrible "fog lights".
Then I installed a cheap eBay oil separator as the engine has overtaxed the stock PCV system. Also threw in a new SMP PCV valve.
All back together now. Fluids topped off, bolts torqued, battery terminal covered, and filter cleaned.
So then I went ORSCCA's AX #1 at Portland International Raceway!
I took second in CAM out of 4 (lost to a Viper ACR, beat an LS2 GTO and a frame-swap Coyote-motored F100). Car was okay, driver is too honking rusty! I am getting a lot of bumpsteer under heavy braking, so I need to take a look at that. Rear end was never a problem, surprisingly. It never wanted to step out and had great lateral grip. Forward grip though...
Yeah, that's serious wheelspin the entire way down the "straight", in second, from a roll, coming out of a 180* constant-radius turn. WHat was it Donohue said about enough power??? 
Beauty shots at the track:
So, I'll be missing the next 2 autocrosses unfortunately due to a death in the family, so the next event is the April 14th Track Night in America at PIR. My to do list for that is to bleed the brakes again, change the oil and coolant, and swap the headlights (the driver's side one got whacked in the hit and run and finally gave up the ghost). I ordered everything up (switching to 1-piece but OE bulbs on the lights), and this came in the day after the autocross, because that's how it goes...
That's how it stands now.
Bumpsteer under braking discussion:
Front suspension is a stock K-member with QA1 tubular LCA's, Eibach Pro Kit coilovers, Eibach sway bar, Steeda bumpsteer kit, and Gripp C/C plates. Current alignment specs are -1.2 degrees camber, +4.5 degrees caster, 1/4" total toe out (1/8 per side). Wheels are 17x9 with 275/40/17 Nitto NT05 and a 1/4" spacer.
Thoughts are as follows: raise the front ride height and look into raised rack bushings to go with the bumpsteer kit. Seeing as how it's camber-deficient, thoughts on putting C/C bolts in the struts to go with the plates up top?
How are you only getting -1.2° of camber???
I think you need better CC plates.
Just curious....how do you know you have bumpsteer under braking?
Sky_Render wrote: How are you only getting -1.2° of camber??? I think you need better CC plates.
The coilovers hit the frame at the top. The smart thing would be to not have coilovers and stick with the spring on the LCA...
Hence why I'm thinking camber bolts on the bottom of the strut to move the base further inwards.
marks93cobra wrote: Just curious....how do you know you have bumpsteer under braking?
At the autocross on Sunday under braking the damn thing would either dart one way or plow straight ahead, like when entering a slalom. If I wasn't under braking, it would turn in normal.
Anybody? Bueller? Bueller?
If the coil overs are hitting the frame, could they be binding and causing the spring rate to go to infinity? Especially if the wheel is turned or one side is slightly more loaded than another?
I also suspect the front geometry is just wrong due to being wrong from the factory and lowering it made it more wrong. You'll want balljoint spacers/taller balljoints to correct the control arm geometry and then bumpsteer correcting outer tie-rod ends or a relocated steering rack to minimize the bump steer within the working range of the suspension (you'll need to add some zip ties to the shock shafts to get an idea of the maximimum bump range encountered on a run after figuring out where it sits at static height after being settled.)
Fixing the potentially binding front struts will help as a first step, but more work will be needed after that.
Good luck!
In reply to Stefan:
We backed the camber off so the struts don't touch the frame, that's just what limits any further camber. The LCA's do have taller ball joints and the outer tie rod ends are also taller (that's the Steeda bumpsteer kit). Rack is still in the OE location though, I could do the offset (raised) bushings on it. I suspect that you may be on to something about a bind or hitting things since it only happens under hard braking.
I have stock geometry, but with MM camber plates (-2.5* camber at autocross, adjust down for street). Suspect settings on bumpsteer kit as well as the binding of coilover to frame (look for witness marks).
Measure bumpsteer and see what the results are.
That being said, these cars just generally dont like heavy trailbraking and will understeer with minimal prompting, so there is a possibility that you need to adjust driving style to do more of your braking in a straight line. Darting isnt a symptom on mine, but plowing with little prompting is a breed characteristic.
How to corner with a Mustang:
Sky_Render wrote: How to corner with a Mustang: 1. Brake 2. Understeer 3. Throttle oversteer 4. Hit all the pedestrians
Fixed 
Sky_Render wrote: How to corner with a Mustang: 1. Brake 2. Understeer 3. Throttle oversteer 4. Understeer 5. Throttle oversteer 6. Do a DONUT! 7. proceed forward motion as if nothing happened.
In reply to Javelin:
Jeez. I had to go back to page 1 to verify, but you apparently didn't have the SVT badge before. Looking good!
Mad_Ratel wrote:Sky_Render wrote: How to corner with a Mustang: 1. Brake 2. Understeer 3. Throttle oversteer 4. Understeer 5. Throttle oversteer 6. Do a DONUT! 7. proceed forward motion as if nothing happened.
This was me at the autocross!
Hey corners smarty dudes, what about the front wheel spacers, would that provide some kind of multiplier to bumpsteer?
pres589 wrote: Hey corners smarty dudes, what about the front wheel spacers, would that provide some kind of multiplier to bumpsteer?
Unless the car somehow has negative scrub, yes.
In reply to Javelin:
So I finally had to join this forum to comment.
I sold my 97 Cobra last year I had very similar modifications, except I ended up removing my panhard bar setup and putting in a 2003 Cobra IRS. Subrframe brace and poly bushings and the rear was transformed. It was also a half inch wider which took care of the rubbing issues on 315s (with modified frame bolts)
Glad you are enjoying it. I sure miss mine I loved that car. I am enjoying its replacment too though.
Wonder what the car would act like without the front wheel spacers then. I kind of thought that they would magnify this sort of issue.
Never thought about the spacers. They come with the coil over kit! The front tires hit the struts without them. Starting to think I might want to get a different shock/spring setup and sell this one...
bobjacobson wrote: In reply to Javelin: So I finally had to join this forum to comment. I sold my 97 Cobra last year I had very similar modifications, except I ended up removing my panhard bar setup and putting in a 2003 Cobra IRS. Subrframe brace and poly bushings and the rear was transformed. It was also a half inch wider which took care of the rubbing issues on 315s (with modified frame bolts) Glad you are enjoying it. I sure miss mine I loved that car. I am enjoying its replacment too though.
Dude. Damn. Your Cobra is what I wish mine was, down to the paint color and the IRS. I have to say though, I would totally dump mine for a Boss 302, too.
I miss the wife's old 2012 gt.
I just got into so much damn trouble with the power it had... (3 tickets in as many months.)...
In reply to Javelin:
I got the IRS in a straight swap with a guy who wanted a solid rear for drag racing. I put in a set of 4.10 gears at the same time and that was huge. Those motors really like to rev and that helped a lot.
I ran H&R race springs with bilstiens mm caster camber plates steeda x2 ball joints and a 275 tire in the front without issues. I can't remember my alignment specs exactly but I think it was 0 toe 5 on the caster and -2 camber.
Like you are experiencing it always pushed in tight corners on an auto cross. I learned to drive around it, but it was always the most frustrating part.
Keep at it. I will always have a soft spot for 96-98 cobras... they are getting pretty rare these days.
I'm just about ready for my first Track Night in America on Friday, even sprung for the on-track insurance coverage (only $102). I've done HPDE's before, including one at PIR, but haven't done one in 8 years...
I signed up for the Novice section!
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