"Crash" Bolts???

[cjstringer]

Ok, I was at my local autocross event this past weekend and was looking at how I might be able to get some camber dialed into the front end.
One of the other competitors, and past champions, suggested I get some factory "Crash bolts". They are supposed to be slightly smaller diameter bolts than the factory ones on the bottom of the shocks and will allow for a little variation in the angle so I would be able to dial in some camber.
Has anyone else heard of it? My dealer is acting like I'm being stupid, but he also keeps asking me if I'm sure I don't have an MPV, so he might be the one that's wrong here.
Please help! I would like to be able to reduce some of the understeer for autocrossing and I am thinking this might be a decent start.
Thanks.

 

[derrick1623]

ok, this guy dave has them, ground control makes a camber adjustment plate for our cars!!! its 289 for them, but, they let you have what your lookin for. he's also got it so he can dial in his struts too,hehe

 

[cjstringer]

Don't want camber plates, I need an OEM part to stay stock. Camber plates put me in STS and I am leading points in GS right now. Don't wanna switch mid-season.

 

[derrick1623]

oops, my bad...i keep forgettin about classes, damn rookie i am.geez,hehe

 

[melicha8]

HEY EVERYONE!!! Camber Plates from GC only work for those like me that have GC Coilovers

 

[cjstringer]

I'm guessing this means nobody has any idea what I am talking about. Ok, I'll look into some other options.

 

[dolphin]

cjstringer,
"Crash bolts" are used to return a car that has been damaged in an accident to something like the OEM alignment. To be legal in SCCA right now as I understand it they have to be in the factory service manual and be an OEM part. The service manual normally has the part number listed as well as the parts manual. I will see if I can get a friend of mine to look and see if Mazda has any listed in the parts manual but it may take a day or two.

 

[cfbjr]

From the alldata data I have and the tire wear I've experienced with my race tires, our car already has about a half degree of camber. When I had a track day a couple weeks ago the tire wear on my V700's was dramatic in the way the insides of the fronts were worn down quite a bit more than the outsides which would be an indicator of negative camber. I was going to investigate the crash bolts as well for our cars, just to see what's possible as far as camber adjustment with the MP3, but we do already have some there.

 

[cjstringer]

Thanks guys. After spending about a half hour at the dealership the other day, and them not letting me look at a manual, they printed out or photocopied a couple pages for me to have, but an alternate to the stocks part number wasn't on it. If you could find anything it would be greatly appreciated!

Thanks again.

 

[jmauld]

From the alldata data I have and the tire wear I've experienced with my race tires, our car already has about a half degree of camber. When I had a track day a couple weeks ago the tire wear on my V700's was dramatic in the way the insides of the fronts were worn down quite a bit more than the outsides which would be an indicator of negative camber

1/2 degree of negative camber isn't going to be noticeable. On my autocrosser, I have 2 1/2 degrees of negative camber and it's hardly noticeable. You most likely have your toe out of alignment.

 

[cfbjr]

That was my other thought as well, as toe out would cause that wear pattern as well. I believe we actually have more than half a degreee of negative camber. The spec says -0deg. 49' which I believe would be more like 3/4 degree of negative camber(?). Remember too that I experienced this wear after a full day of road racing, not autocross.

 

[jmauld]

My money is still on the toe being off.

 

[Zeus]

Eibach sells camber bolts, as well as most good alignment shops. Just know the dia and length of the strut spindle mounting bolt when looking for the adjusters. Be aware that these buggers can seriously play with the toe in. Normally youll get about a full degree of camber adjustment with them, but for each degree of change in camber you get about a degree of change in toe. So if you use them, plan on going doing a full 4 wheel alignment.

I think the Pros work well with front camber anywhere from 1/4 to 1 degree because of the ample caster dialed in stock. The rear is a little bit more sensitive and depending on tire width and pressure 1/2 to 3/4 works for me. Rapid wear of the inside front tread is most likely a combination of toe and tire pressure. Even with the alignment properly set, a high tire pressure in front will move the contact patch to the inside on hard cornering. This may contradict most peoples opinion, but with a slightly lower pressure the tire will roll over more and the contact patch of the outside front tire will move to the middle of the tread in cornering, resulting in better grip and more even wear. The draw back is that turn in may take on a vague mushy feel.

I think most people will agree that a well set up street suspension and alignment will not necessarily equate to even tire wear in competition, with the reverse also being true. The bottom line is you cant have both, and there is a lot to consider when setting the suspension up for an aplication.

 

[cfbjr]

I feel ya Zues. It's hard to find the middle ground. I guess that's why people have purpose-built racecars.
I think it is a matter of toe.
The wear goes from the middle tread block all the way to the inside block. The outside block had a lot less wear than the others. I did run fairly high pressures (42-44in front and 40-41 in the rear). The rear showed similar wear but to a lesser extent.
I am going to use my street tires this Saturday's track day because I want to use the V700's for the remaining autocros season. The track days wear the hell out of the V700's.
Especially now that it's getting very hot.

 

[ktm173]

Hey Carson,

You're going to the Thunderhill street school Saturday?

I'll be there, but not sure in which car yet - most likely my '00 ES, as the road race MR2 has a leakly cam seal (found out last night - arg!) But maybe in the Type-R.

Kevin M.
'00 ES daily driver....

 

[cfbjr]

Aw geez, the Type R? If you bring the ES at least I have a chance of not being the slowest car out there. You'll probably still drive faster than me, but at least I won't feel way overclassed by the Porsches and Vettes. See you Saturday.