Dr.Ron

I have a 2011 Carbon Edition on 19/20 Pilot sport cup ZP's currently.

My prior alignment was: Camber -1.5 F/ -.9R,Toe out F .18*, toe in .10 rear.

I wanted to add more -camber so as to not wear the cup tires poorly.

New specs are: Camber -1.7F/ -1.1R, Toe out F .05*, R toe basically 0.

I know the specs have not changed much and I am not out to set any track records, but will I experience any changes handling wise??

Thanks!

Ron

05dsom

That's what I did last summer, along with switching to MPSC's as well...transforms the track handling ( I use PTM 5) of the car and really makes it more responsive (a little more tram lining with the tires) and softer ride when in TOUR mode on the street

I had the stock alignment before though, so I should see a more dramatic change than you.

i used the Pfadt Performance street-track use with race tires spec:

Dr.Ron

I only use those tires for the track myself. I used the PFADT specs as a guideline.

dapopa9

Just an FYI...PFADT recommends a Toe IN setup on all the configs. Up top you mentioned you are running Toe OUT.

Lawdogg

I'm not sure what Mich. recommends as the alignment specs for the sport cups, but the factory alignment specs for the ZR1s that came with the sport cups might be a good starting point. The changes that you specifically made to your alignment probably won't be very noticeable. Maybe a little more understeer due to the reduced toe out in the front. With the factory rubber control arm bushings, there is so much deflection that your actual negative camber under cornering loads will be much less than the static alignment specs.

05dsom

so, poly bushings are the next step to improve cornering/handling?
what all is involved in swapping them out?

Lawdogg

Check the Pfadt alignment specs posted above. You can see that the recommendations take into account the bushing material. I had poly and it helped, but the deflection was still more than I wanted so I went with a monoball setup. Swap is very labor intensive. I hired it done and it does cost some $$.

froggy47

I would toe in the rear some. It doesn't hurt wear much & improves rear grip a bunch.

Dr.Ron

I only used PFADT's #'s as a guideline.

It actually is SLIGHTLY in...like .03*, but I was thinking to add back some more toe in out back...I have seen some suggest 0 toe in the rear...some say toe out the rear...

naschmitz

Remember those guys because they are totally wrong.

You NEVER want toe out in the rear, even under extreme bushing deflection. I decided during one of my alignment sessions to toe out the rears just to see why. It was very fun! Car would not drive in a straight line.

Dr.Ron

I hear that!

racerns

I would recommend even more neg camber with the sport cups. I run -2.0 front and -1.8 rear. I also have been running 0 toe front and rear.

Dr.Ron

The thing is, I don't want to totally wear my street tires badly. in the fall after I'm done I'll switch the alignment back to street.

LG Motorsports

Toe out in the front is the only useable setting.

3/16 Toe OUT front will help turn in and balance the car. we usually start with 1/8" out and see what the car/track wants.

3/16 Toe IN at the rear keeps the car stable under braking and allows good driver feel with hard acceleration. You are correct NEVER use toe out in the rear.

on a street course (very tight corners) we would run up to 1/4" Out in the front. but we start with 1/8" out front 3/16 in rear. always.

We always used Spherical bearings on our suspension but urethane upper fronts did not hurt the handling much.

stock rubber bushings change the settings depending how the forces are applied. (Braking, cornering etc.)

Braking loads pull the Lower arms toward the back of the car and the upper arms toward the front of the car. Just think about what that does to everything from toe, caster and alignment. TOO MUCH to fight. Braking forces have the tires holding the car back so the bushings deflect.

Cornering forces on stock rubber bushings act differently on each side of the car. Outside lower A arm gets pushed in and inside Lower gets pulled out. (uppers are opposite)

Remember on Acceleration, the rear lower arm moves forward because the tires are trying to beat the car. that changes the toe and rear bump steer so the car gets loose and thus needs more toe in with rubber bushings just to keep the rear under the car.

Hope this gives some insight and also why any track time set up is a compromise without a full track set up.

So with Rubber stock bushings, align it conservative, just make it comfortable to drive hard. More toe in at the rear helps with that. The rest is a crap shoot unless it is a track dedicated car.

thanks

Lou Gigliotti

Dr.Ron

Thanks for stepping in here Lou and giving your insight!
Your toe #'s mentioned, are they per side or total toe #'s? I'm thinking total toe, yes?

froggy47

More.

mountainbiker2

This is mention a lot. I just don't get it. Total toe should be the only number you give.

Steve

troyguitar

Do you run those kind of settings on a street car? I was thinking more like 0 toe in front and 1/8 in rear for a true dual use car - maybe I'm being too conservative.

Crepitus

Thanks Lou. I'm a huge fan of your motorsports as well as politics

If I can add, A lot of - camber with a lot of toe out is really hard on the inside edge of the fronts on a street car. The good news is the toe is easy to adjust. Adjusting to very little toe while leaving the - camber alone should wear quite nicely. When you need lotsa front grip with nice turn in remember how much you had to turn the tie rod adjusters and set the toe to race spec. If you can use a square tire size with symmetrical construction tire rotation will help a lot too.

LG Motorsports

Hi,

Yes, Total Toe. Back in the Corvette Challenge sometimes we would have to use the Rear toe to make the car turn because we were stuck with a totally stock spring and bar set up.

It was really squirrelly but if we ran zero toe or even toe out on one side, we could make the car turn on a slow street course. but it was a real hand full on the medium and high speed corners.

You can gain better lap times when the driver is comfortable and can drive with confidence that the car won't do anything unexpected.