Cal Club Autocross Forums

For several reasons I think I need to lower the front of my car 1/2 -3/4 inch. Can be done on factory suspension w/out mods.

What affect does that have on camber, toe, and caster?

Steve Towers wrote:For several reasons I think I need to lower the front of my car 1/2 -3/4 inch. Can be done on factory suspension w/out mods.

What affect does that have on camber, toe, and caster?

Depends on the car is the answer to both questions.

Steve,

I lowered both the front and rear of my car on the Z06 when I had stock Z06 shocks. This was on the stock bolts. The front lowered about 3/4 inch, and the rear came down about 1inch. Don't know about a non-Z06 FRC however.

Tom

Tom Dobyns wrote:Steve,

I lowered both the front and rear of my car on the Z06 when I had stock Z06 shocks. This was on the stock bolts. The front lowered about 3/4 inch, and the rear came down about 1inch. Don't know about a non-Z06 FRC however.

Tom

Got similar results on my old C5 ...





DIY http://www.z06vette.com/forums/f117/diy ... c5-107705/

Lowering the C5 changes everything in your alignment.

Maybe I didn't ask the question correctly. I know HOW to lower the car, but I'd like to know which alignment settings change when you do it. I think the negative camber increases, which for me is good, but I don't how much other aspects, such as caster and toe, are impacted. The car is currently lowered about 3/4" all around, but because of new rear tire height I need to re-establish the rake by either lowering the front or raising the rear. Or a combo of the two.

C5 Hardtop (Z51) 04 Z06 shocks, Z06 front bar. Currently maxed on front neg camber at 1.6

As Mako said and you already know the alignment changes. There is no point to speculate what changed or by how much. You should just go get a new alignment.

You'll get surprisingly massive change in toe ... make sure you have them max out the Caster when doing your alignment.

Steve Towers wrote:For several reasons I think I need to lower the front of my car 1/2 -3/4 inch. Can be done on factory suspension w/out mods.

What affect does that have on camber, toe, and caster?

Steve lowering the car will effect everything. On the Z06 I lowered it all the way to the stops

If your driving the car on the street I would try these setting:
Front:
Neg Camber: 1.75 degrees with zero to 1/16th" total toe out. Stock caster setting or slight inrease.

Rear.
Neg Camber: 1.25 degrees with 3/32" to 1/8th" total toe in. Stock Caster setting or slight increase.

If not for street use you could go to 2.25 neg camber on the front, Maybe 1/4" total toe in at the rear and max the caster.
Have Fun! Steve

Thanks to all of you for the help. After seeing what ya'll had to say, it seemed a good idea to look at the printout from my last alignment. The stock caster for my car should be 6.5 nominal. Well, it's 3.25 left and 3.8 right - just about 1/2 of what it should be. The cross caster is .55, which is over double what it should be.

I'm thinking the highly thought of (Orange County) shop that did the work didn't do such a hot job. Also, the rear camber is 1/2 degree less (per side) than what I asked for.

My bad for not scrutinizing the readout before leaving the shop.

Steve Towers wrote:Thanks to all of you for the help. After seeing what ya'll had to say, it seemed a good idea to look at the printout from my last alignment. The stock caster for my car should be 6.5 nominal. Well, it's 3.25 left and 3.8 right - just about 1/2 of what it should be. The cross caster is .55, which is over double what it should be.

I'm thinking the highly thought of shop that did the work didn't do such a hot job. Also, the rear camber is 1/2 degree less (per side) than what I asked for.

My bad for not scrutinizing the readout before leaving the shop.

You could try Darren @ Westend Alignment, 310-808-9233. Let him know what you car is doing an he'll recommend a solution.

Sometimes it takes a week or more to get an appointment with Darren ... use to be cash only. Try to get an early appointment ... if it's late in the day he will be way behind schedule and you will have to wait. He doesn't allow himself to be rushed and he won't quite the job until it's perfect, even if you say enough is enough. He's had a second alignment rig for the past few years but he's had trouble finding someone good enough to keep. It just slowed things down because he kept double checking the other worker. I was there one day when he sent his helper son packing.

btw...West end is pretty open all next week.
I'll be there Wednesday.

Chad,

We may cross paths. I'm Scheduled for Wednesday at 2pm.

Thanks to all for their input. FWIW - I looked online for reviews of the West End's work - Wow, the dude must me the alignment God.

Mines at 11
takes around and 1 - 1.5 hours.
you will be happy

I think you guys have it wrong. There is no alignment god...there are no correct alignment targets. Camber, toe and ride height are variables that you should be using to get the car to behave the way you want it to. When my Z06 oversteered, I lowered the rear only about 1/16th inch, making a noticeable balance shift. Other cars have responded more to rear toe and I sometimes alter that at the track.

If we're talking late Corvettes here, talk to Tom Berry or Gary Thomason about what they changed for what purposes. And experiment. Corner me at an event and I can give you a run thru of how you do your own alignments. Big bucks not a requirement.

[quote]I think you guys have it wrong. There is no alignment god...there are no correct alignment targets. Camber, toe and ride height are variables that you should be using to get the car to behave the way you want it to. When my Z06 oversteered, I lowered the rear only about 1/16th inch, making a noticeable balance shift. Other cars have responded more to rear toe and I sometimes alter that at the track.

If we're talking late Corvettes here, talk to Tom Berry or Gary Thomason about what they changed for what purposes. And experiment. Corner me at an event and I can give you a run thru of how you do your own alignments. Big bucks not a requirement.Bill Martin

The "Alignment God" comment was a tongue-in-cheek comment. I pretty sure every one agrees that a setup that one person is comfortable with may not suit another persons driving style. In my case my C5 got reclassed to A stock, so I had to make some changes to bring it in to compliance. The car handles considerably different due to the changes coupled with a poorly done previous alignment. And I need to change out the front upper a-arms. After talking to a fair number of 'vette folks, including Gary and Tom, I want a pro to set the car up to some baseline numbers. Once I know where I'm at and how the car handles, I can then tweak it as needed. Gotta start somewhere.

Yeah, that sounds like an okay plan. I guess I had two points. How will some alignment expert at a shop know what previous top competitors have evolved to, alignment-wise? And two, will you feel comfortable changing his alignment yourself if you didn't do it, and may not be able to reproduce it? Hence, DIY. Alignment isn't magic...everything worth doing can be done in your driveway with hand tools and $20 worth of stuff from Home Depot. DIY isn't for everyone, but it's not the big deal some people fear. And it's a serious development tool you're throwing away if you just turn your car over to a shop.

Bill Martin wrote:How will some alignment expert at a shop know what previous top competitors have evolved to, alignment-wise?

I took it to mean that the guy does very precise and thorough work when aligning the car, not that he can divine the proper specs. As opposed to the shops where they give you the minimum-time-on-the-rack, that's-good-enough treatment.

How will some alignment expert at a shop know what previous top competitors have evolved to, alignment-wise? And two, will you feel comfortable changing his alignment yourself if you didn't do it, and may not be able to reproduce it?

I'll give him the numbers I want, based on all my conversations in the past 60 days, and yes, after establishing a "Zero" I'll be ok with making adjustments. I understand that the numbers are just reference points, but I think using settings that others have had success with is a reasonable place to start. To some extent I'm on my own by being a non Z06 C5. Other than a small group of ASP cars (Gary, Tom, Steve Abbott) there's not much experience to tap into.

My Z06 is long gone, but I still have the suspension file with the various recommendations. As you say, aren't sure if they translate to a non Z06. But it sounds like you already have similar info.

Steve Towers wrote:

How will some alignment expert at a shop know what previous top competitors have evolved to, alignment-wise? And two, will you feel comfortable changing his alignment yourself if you didn't do it, and may not be able to reproduce it?

I'll give him the numbers I want, based on all my conversations in the past 60 days, and yes, after establishing a "Zero" I'll be ok with making adjustments. I understand that the numbers are just reference points, but I think using settings that others have had success with is a reasonable place to start. To some extent I'm on my own by being a non Z06 C5. Other than a small group of ASP cars (Gary, Tom, Steve Abbott) there's not much experience to tap into.

I hate to disagree here, but if I were you Steve, I'd give him your specs but also be open to his suggestions. Me thinks you will enjoy the conversation. Darren isn't pushy and will do exactly as you ask. That said, ask for his opinion. If nothing else, you'll get a great primer on alignment. Let us know how it went.

I hate to disagree here, but if I were you Steve, I'd give him your specs but also be open to his suggestions

George, you lOVE disagreeing. When I made the appointment I told Darin (Darren?) that I had some numbers in mind, but I would certainly appreciate his input. He said "Perfect". Almost everyone knows more about this stuff than I do, but I'm listening and learning. If I'm not willing take advice from folks that are acknowleded experts in their profession, then I'll just be another Obama.

Darren, at least use to, did not like doing "extreme" alignments, because he didn't want folks blaming him for their poor tire wear. The fact is fairly heavy negative camber alone won't necessarily cause poor tire wear, especially if evened out with "sporting" driving, but lots of Toe will. Imagine if you have an 1/8 inch amount of toe. That mean with every rotation of the tire it has to scrub an 1/8 inch. A 245/45/17 tire does something like 785 revolutions per mile. That 1/8th inch amount of toe equals about 98 inches of scrubbing every mile! THAT'S what eats up tires. It really isn't that difficult to keep your toe around zero for the streets and add in your competition toe settings at the track.

Some drivers very actively use toe as a tuning tool. Eric Sung, one of the few local drivers that was able to beat Ken in ST, with an RS Subaru at that, would custom set his toe after doing his course walk ... making his car looser or tighter by adjusting both front and/or rear toe. This after going to Darren something like 10 times!

STX National Champ Josh Sortor used an especially low mechanics crawler to get under the rear of his STX WRX so that he could adjust his rear toe ... in Grid. It was fascinating watching him and Jeff Barco trading times at a National Test and Tune. Josh finally did beat Jeff with a couple of in-Grid rear toe adjustments (using his adjustable rear WRX links.)

Tom B. mentioned to me how one can continuously compensate for the wear of the rear C5 tires by increasing the rear toe-in.

It really does pay to learn how to do ones own alignment work. Here is a long rambling thread on DIY alignment: http://forums.nasioc.com/forums/showthr ... ?t=1093484

I've used the string method and didn't care for it. I used to use homemade trammel bars, but now use Longacre toe plates:

http://www.longacreracing.com/catalog/i ... 52&catid=5" onclick="window.open(this.href);return false;

If you don't want to spend the $60, you can easily make up something similar out of scrap.