Alignment specs..?

I know i saw a thread on this before but after searching couldn't find it...

What you guys setting your alignment specs too?

I need to realign my car this week or next before CMP and was curious what everyone else is running?

Eric - this was from my last full alignment with Cooper:

Left/Right Front - Camber -4.0 / -3.9 respectively
Left/Right Front - Caster 9.3 / 8.8 respectively
Left/Right Front - Toe -1/16in / -1/16in respectively

Left/Right Rear - Camber -0.2 / -0.2
Left/Right Rear - Toe 1/16in /1/16in

0 degree thrust angle

Devin, I think 4deg of camber is way to much, while for the BMW 4deg was good, i found that braking was a problem for me with any more than @ 2.5degress of camber. DO you have problems with brake lockup?

Even Chuck Hawks struggled to not lockup my car with 3.8-4deg with brand new Michelin slicks on the car!

Greetings ... I run -2 degree camber & low 5's in caster ; very balanced ... My biggest challange was to square the car , the Texas boys had it farly twisted out ... How do you adjust the rear w/ a straight axle ??? Any one figure out how to retuce the tremendous bump steer in the Ra's thanks / Paul W.

I know i saw a thread on this before but after searching couldn't find it...

What you guys setting your alignment specs too?

I need to realign my car this week or next before CMP and was curious what everyone else is running?

Eric,
this is totally dependent on the other key setup factors in each individual car. Likes of tyre type (Slick Vs DOT), tyre size, spring rates, shock setting preferences, bar preferences track configuration. I do not believe there is one set up that will suit all or even most cars. The factory specs are a start point but thereafter individual tuning is a must.

We use LF -3 camber, RF -2.25 camber. 1/32" toe in LF/RF. Caster 5 degs LF/RF. This is a DOT endurance set up for a predominantly RH turning track with very fast sweepers.

I have a pair of front 255/40/17 Kumho Victoracers that have now done 2 6 hour races and probably a total of 14 hours track time and still have some life left in them. Lap times, tyre wear and driver feedback are how we gauge our alignment setup. Thereafter change in track condition is allowed for in shock/bar/pressure settings.

Hope this helps, Kel.

Greetings ... I run -2 degree camber & low 5's in caster ; very balanced ... My biggest challange was to square the car , the Texas boys had it farly twisted out ... How do you adjust the rear w/ a straight axle ??? Any one figure out how to retuce the tremendous bump steer in the Ra's thanks / Paul W.

Paul, we have not experienced any bump steer in our RA. I would make up some bump steer boards (all you need are 4 squares of plywood, 4 hinges and 4 long screws to make them up) remove your spring/shocks from the front end and check for bumpsteer through the full range of droop/bump.

I know from a previous thread, different cars have differing steering arm setups and this certainly could cause bump steer issues if your combo is incorrect.

Kel.

Thanks kel, and Devin. I know it varies, I have typically run -2.5-3deg of camber LF and RF, max caster @ 7-8deg. and 1/8" total toe out(1/16" each side, was just curious what some of the other guys are running. I have 3-4 straights of track time coming up next week and i want to play with some suspension tuning and try to get the car really dialed in

Thanks kel, and Devin. I know it varies, I have typically run -2.5-3deg of camber LF and RF, max caster @ 7-8deg. and 1/8" total toe out(1/16" each side, was just curious what some of the other guys are running. I have 3-4 straights of track time coming up next week and i want to play with some suspension tuning and try to get the car really dialed in

No worries Eric. What makes it a little difficult to know what would work for your car compared to likes of mine is, while you will have additional grip from your slicks which would normally require a tad more camber, you also have higher spring rates and hence less suspension deflection happening. There are to many conflicting variable to know..........so only tyre temps and wear patterns will truly provide the right picture.

I'm running about 1.75* negative camber, 8* caster and about 1/8" total toe OUT. I'm all about getting the most life out of my tires though. More negative camber may provide faster lap times at the expense of the inner shoulder of your tire. I'm happy with how the car handles.

Left/Right Rear - Camber -0.2 / -0.2
Left/Right Rear - Toe 1/16in /1/16in

How are you adjusting that?

How are you adjusting that?

We got some slight adjustment by "adjusting the two long bars (technical definition) that run along the side by the exhaust:

http://dcazin.c4-motorsports.com/PanozGTWCGT2211/img_6701.html

Hope that helps.

Kel ... Archer Racing measured the bump steer when I first got the car ; two years ago ; from memory , they were shocked that it had so much bump steer, measured w/ a dial indicator ( .048) ... My arms are aluminum , about a inch thick ... There was a earlier thread that showed machined set of arms w/ narrowing of the ends by about 40% ; raising the tie rods ... Talked w/ Panoz Engineering , they said they knew where I was going , but of coarse could not advise !!! I have left them alone ... Thanks / Paul W.

Rear settings are mostly FYI, and not adjustable, only way to add camber is to heat the axles!

Adjusting the lengths of the rear four link bars can only significantly change pinion angle and thrust angle. Correct? I believe Eric is correct that you would need to bend the rear axle housing to change the rear camber or toe and that would have definite practical limits. Changing the location of the four bar frame mounts would change the rate of pinion angle change as the suspension moves through its range of travel. Correct?

Mike

Eric, Whats up with trying to make you car handle better. With all that LS horse power you should be good to go for CMP, or are you second guessing yourself thinking how can I be so fast with only 225hp.

Adjusting the lengths of the rear four link bars can only significantly change pinion angle and thrust angle. Correct? I believe Eric is correct that you would need to bend the rear axle housing to change the rear camber or toe and that would have definite practical limits. Changing the location of the four bar frame mounts would change the rate of pinion angle change as the suspension moves through its range of travel. Correct?

Mike

Yes Mike, you are on to it. 4 bar adjustments can change pinion angle and alignment (toe settings, but toe changes are obviously not independent).

To camber the rear end, either weld across the housing to bend it or put it in a press and bend it. Need to be careful about how far you go though to avoid accelerated axle spline and bearing wear. I had approx -3/4 of a deg put into my last cars 9" with no probs. Was used for sprint racing though so not big miles to find out what wear rate would have been.

I note that my car aready has some welding across the tops of the housing but assume this was to correct the housing when manufactured as it has not detectable camber in it.

Kel.