taken19

Now that I'm figuring this road race thing, I'm learning about suspension and alignment fundamentals. Still running factory C6 Z51 suspension (loweredon stock bolts with rear bushings cut) and street alignment. I have taken 6-7 seconds off my lap times at Homestead between the last two events by improving skill and understanding the car (from 1:58 to 1:51).

I have been reading the DIY articles for track alignment setups and it doesn't look difficult at all with a few basic tools. A couple questions though...

1. How high do you get the car up to access the tie rods and A-arm bolts? I was thinking 3-4 inches by driving up on 2x10" planks stacked.

2. By adjusting camber first, how much difference will than have on toe? Minor or significant?

3. I was gonna ompare the iPhone level with a carpenters level for accuracy. If it is close, I may use the iPhone since it will read tents of a degree. Am I out to left field here? Do you think there will be any issues with repeatibility?

4. After my first attempt, I'm gonna drive around and re-measure. What's the likelihood of an alignment shift? I would guess a small chance as long as the car remains on the ground the entire time (suspension does not become I sprung at any time).

I appreciate any suggestions.

Sean

sla07

cant answer your questions as im a n00b at this...

were you there yesterday by any chance?...i was in the C group...silver 09 stock c6...

taken19

Yes, I was the orange C6 with the blue tape on the nose and rearview mirrors. First time in intermediate, but learned a ton on my alone with experimenting on turn in points and braking zones.

msracing

Sean good meeting you yesterday.. we had a great time ,,, be back out there next weekend... call me sometime and will walk you thru what we have done...

Manny

sla07

Sweet!!...yea I was in the C group with a couple friends, one was a black z06, one was a white BMW 135i...and the other a silver Audi...

The Bimmer and z06 are going next weekend..I might go to watch a little...

I saw you out there...looked good on the front straight...couldn't see anything else though...my instructor was one of the two guys driving the black really loud with big spoiler BMW m3...very good instructor...

taken19

Manny, good to finally meet you as well. I would like to hear more about your custom oil cooler setup. Sounds like you have a good system for the right price. Maybe I could buy some of those custom made brackets from you when I pill the trigger? I don't have access to a welder or other fabrication machinery.


Sean

taken19

I went with 2 guys in group C. A silver M3 and a black C6 with silver hood stripe. Yesterday was my first time in intermediate - learned a lot while experimenting with turn in points and braking zones. I was very happy to gain 6-7 seconds on my lap time. I really think the stock alignment is holding me back now

sla07

Aahh yea I recognize both of those...I had to let the m3 pass me at one point lol...although I passed the c6 ...

How much more did you learn on your own?...I mean did you feel that you could push a little harder since there wa nobody else in your car?...my instructor times me on one of my laps and tagged it at 1:51...figured I was slow but for my first time he sai that's pretty good...

kimmer

Your suspension needs to be loaded.

taken19

The Instructor was invaluable to get the line and specifics regarding the track. On my own I got to play a bit with turn in point and try later braking. This could also be the product of 5 more sessions under my belt though.

He M3 has almost $10k worth of suspension and brakes and an aggressive track alignment - almost 3 degrees of negative camber! He was running consistent 1:54's on street tires and squeaked out a 1:51 on the last lap of the day with no traffic in front of him. I ran consistent 1:52's all day yesterday and ran 1:57-1:58 last time. My problem was trying to learn the car AND the track at the same time after a H/C/I swap.

The C6 guy has only driven his SC car on the track once before so he is still learning the car. His runflats weren't helping him out at all either...

I'm pretty sure I've outgrown my stock alignment since I was pushing the PS2's hard based on their feedback. I even swapped back to runflats for one session and was sliding all over the place!

Running a 1:51 in group C is moving. As long as you felt comfortable in the car, you will advance In no time at all. Look for me at your next event and I will do the same. We can swap stories.

Sean

sla07

Yea that m3 looked like it was planted...looked like my friends z06...

Ah so your frien in the c6 was still getting a feel for the whole thing...only way to do it is bein out there...

Yea it's possible that you are hitting the limits at this point...I asked that in the thread I posted in thi section...I felt comfortable with the exception of brakes and what I felt was body roll...for some reason I feel I needed better brakes, stiffer suspension, and sticky tires (not fire hawk run flats)...the instructor asked me to back off of turn 10 a little bit because he felt that I was hitting the line great but the car would slide slightly to the right...says that the tires are good but wouldn't recommend I push any harder with these...so I obliged......

Yea man next event I'll be sure to look for you Sean!!...im Luis!!

froggy47

You HAVE to have a leveled area to do it, there are a few ways to do that.

Biggest problem is the binding of the stock suspension control arms.

Best luck, when you figure it out it is very satisifying & very accurate to diy.

taken19

Luis,

Yeah, turn 10 doesn't leave a lot of margin for error with a big bump and outward banking.

If you haven't already, look into stainless steel brake lines, carbotech XP8 and XP10 pads and a high quality fluid. The Quantum Motorsports brake duct coolers work well also. That combo makes a world of difference from the stock setup. Very stable!

And that M3? He was entering turn 10 at 110 mph on street tires! He has way more ***** than I do, but he almost lost turn 10 a couple times...

0Fred@ReverseLogic

Which iPhone app are you using? I like iSetSquare since it works in both horizontal and vertical orientations. It is also very easy to set a relative 0˚ starting point.

sla07

Awesome...I will check those items out...thanks!!

Yea I definitely didn't hit 110 on that turn but I'm guessing I was hitting 80's to 90's a time or two...maybe higher when the instructor told me to back off lol...

taken19

I current have iHandy Level because it was free. I would imagine that the accuracy would be the same between apps but that's just a guess. I figure as long as its calibrated properly I should be fine.

gkmccready

I agree with froggy47. Car must be level and must be settled. I also like the SmartCamber tool, well worth the money. Check, check and re-check. Setting the alignment on the C6 is not something you will do quickly as a DIY.

Keep an eye on your bushings. Even on my stock runflats I was generating enough force to walk the bushings in the arms. Also, keep an eye on your oil pressure -- I'm still waiting for my C6 to come back from the dealer with a new motor in place (although, right now they're looking at the diff!). I would NOT track an LS2/3 C6 on DOT-R tires (yes, even R888s!) any more.

I'm at a huge decision point with my car...

davidfarmer

some tips here...

http://www.davidfarmerstuff.com/align.pdf

a drive-on lift (4-post) is the best way to go. If not, you are pretty much forced to measure, jack, adjust, lower, drive around the block, remeasure, repeat......... But, you get the hang of it and hit your goals pretty quickly.

You must set camber and castor first, as Toe is the only adjustment that doesn't change other things, so it must be done last. Don't worry about toe/thrust angle until you are completely finished with Camber, or you'll just keep going around in circles.

I have a bubble gauge that I use most of the time. I have a digital level, but it's too easy to get hung up by 1/100th's of degrees. You just can't get it that perfect. As in my guide above, a good estimate can be made with a straight edge and a level. 1" of lean is roughly 3deg, and you can interpolate from there.

sperkins

2 tape measures
2 four foot long capenters levels or toe plates
1 laser level
1 digital protractor

If you've never done it before or don't have access to a 4-post lift, go ahead and shave your head. It'll save you the time and pain from pulling it all out. Especially if you're on stock rubber bushings.

taken19

Sounds like you lost a motor due to loss of oil in a high G corner? If so, sorry to hear that. I run about 3/4 quart high right now on PS2's and was thinking about an accusump before I put on R compound tires.