I'm moving from 16" to 18" track wheels and need to reduce camber accordingly - some have suggested down to -0.2 degrees.

At the extreme end of adjustment (most positive), I can get the rear camber on one side to about 0.0 deg, but the other side the most positive I can get is -0.4 deg.

Has anyone experienced this and are there other methods (e.g. a source for aftermarket camber bolts for the rear) for increasing camber adjustment range, or biasing the suspension towards more positive camber?

I tried shifting the other suspension attach points as much as possible, but there isn't enough slop in the bolt holes to make any difference.

I will make adjustments based on track results, but it would be good to have some adjustment range around -0.2.

 

I believe people sell adjustable rear control arms. The longer the lower control arm, the more negative camber you will get and shortening will give you more positive camber. I'm sure someone also sells adjustable front arm, either upper or lower. If its the upper arm, more negative will be a shortening it, and more positive would be lengthening it.

When you say race track, im assuming your talking about the drag strip since you want near 0 camber?

 

When you say race track, im assuming your talking about the drag strip since you want near 0 camber?

But then why in the world would he go from 16" to 18" diameter wheels.

IDK, my head hurts...

 

Gotta look cool! B)


I hope your doing an alignment each time you touch the camber. For the front the toe and castor measurement change when you touch the camber.

 

Hafta say, I think the source that says that -1.5 camber for 16" wheels and -0.2 camber for 18" wheels for the rear of the FD are equally appropriate is a bit off...

If you're doing road course or autoX, IMO you want at least -1.5 in back whether you're on 16s or 18s. Optimal static camber depends on a number of factors, but I seriously doubt that -0.2 is going to be good for anything but drag racing...

 

Thanks, that could well be - I only have experience with the 16" wheels so I'll leave it where it is then and see how it goes. I will be fine-tuning with a pyrometer and was just hoping to get close for the first day.

This is for a road course. These are 18x10 Forgestars with 50mm offset, which will have 285-30-R18 Bridgestone GForce R1s mounted. Where have others ended up with camber settings?

Other responses:
Yes, I realize I need to adjust caster and toe-in when changing camber on the front. And it is very time consuming...

Thanks for the pointer to the adjustable control arm - I'll go that route if I need to.

 

-2.4 Front
-1.2 Rear
Stock sways
11k/11k springs

18x11 +45 Forgestar F14 Front/Rear
295/30-18 Ventus TD and R888

I didn't set it with a pyro, but that kept me from wearing the outside shoulders off the tires.

 

^Yeah, but you mostly autox iirc, while PrimerGrey does track days and is pretty quick.


Last time I tried, I don't think I could get my rear camber lower than -0.8. That was before I replaced all the bushings with Mazda Comp. I'm in need of another alignment... I think I wound up settling at -1 or -1.2 at the rear with about -1.5 up front.

 

Yup. I ran the same on the street/street tires though.

I think the main thing is I never had any power, so I didn't have to use the brakes- braking is where too much negative camber up front will kill the inside of your tires on the circuit.

 

I really think the Pettit recommendations for 18" wheels are WAY on the low side. -0.2 is going to turn into a fair amount of positive camber while cornering.
Also, it's not like you can assign camber based on wheel diameter. Of all the factors in play, that's *way* down on the list of importance. Wider tires don't need as much camber as skinnier tires, but even 295s on 18s can use a LOT more than -0.2 degrees!

FWIW, I ran -3 front and -2 rear all last year, street and track, on 255/40-17 and 275/40-17 Nitto NT01s, and they wore pretty evenly.

IMO -1.5 is about as little as anyone going to the track would want for rear camber, and even street only I don't think I'd run less than -1.

 

I'm on max camber