Phoenix64

When I got the car, the left front bolt was almost full down, right front 4 turns up. Rears were opposite, but the ride height measure from the the jacking pucks was within 1mm front and 2mm rear. With about a half inch of rake. Fender gaps were all about the same too.......BUT

Found a shop that would loan me scales for 40$.

Full of fuel, only mods a Momo steering wheel, and borla exhaust.




Zeroing all the bolts got it pretty close, 2-3 adjustments later.....



Seriously do you guys think this is close enough? I also got the car aligned, camber and toe were way off side to side.

After all this the car changes direction like a cracked out spider monkey. Its almost too responsive, and a little nervous feeling. Could be the 0 toe.

bdanyluk

Gained 200 lbs from 1st shot to second shot.

So you sat in the car then?

So then it's not an apples to apples comparison.

If you had the same Weight in both shots, i.e., you sat in the car in the drivers seat both times, then it would be a better comparison.

Sitting in the car dramatically affects the loading on the tires.

Phoenix64

Here is your apple. Same number of threads on each bolt, me not in the car.

froggy47

IIWM I would not corner weight with a full tank, but that's just me.

strano@stranoparts.com

I'd corner with a full tank... because that's how I run my car.

Looks good "after". How different are the bolts now, just curious. My car is going back on scales next week (it's too cold to work in my shop right now). I'll be curious how yours compare.

fatbillybob

FYI:
Corner weight with 1/2 of predicted fuel load and driver weight properly distributed in car wearing all gear. Fill any cool suit tank too as raced. Tires with hot air pressures as raced.

Phoenix64

They were within 1/2 - 1 turn in the front, and 2-3 turns different rear.
How close do you shoot for Sam? I figured less than 1% cross weight was good enough for a daily driven car that see's 2-3 track days a year.

While I was at it, I weighed my Formula with your Springs, Bars, and koni shocks. Needless to say I was pleasantly shocked with how close the corner weights were. Car is full of fuel, no driver, and about 50lbs of sound deadener in the back.
Thanks for making a great product.

Xian

For a street/DE/autox car, I like to get within a tenth or 2 on cross with 1% variance being more like the initial starting point.

BTW, are you using slip plates or ramps when you get the car onto the scales?

Sidebar: curious about this ^^^. Mind sharing the reasoning? Is it a matter of reducing slosh/weight migration, front to rear weight split, or does the extra weight in the rear aid with rotation or putting down power? Thanks!

froggy47

I tried that once, but the flaggers got mad at me stopping every lap to top the tank off.

Painrace

Corner weight is very important! Ride height, not so much!

Jim

Xian

Why is ride height not important? Too low and you're into the bumpstops, too high and you've raised the CG as well as missing out on some of the camber curve. That's without even look at the impact of rake on handling.

Or do you mean that ride height "for looks" isn't important?

dhowdy

Which is? My front seems to sit right, but for some reason the back seems high despite lowering as much as I could... wondering if raising the front for less rake may help.

Xian

May help "what"? Are you trying to get a certain "look" from the ride height or tune the car? I'm not trying to belabor the point or anything, just not sure I understand what you're trying to do.

The less front to rear rake you have, the tighter the car should drive (based on feedback from folks with way more seat time in these cars than me). My personal experience in other platforms has mirrored this though the Corvette may be more sensitive to rake than other cars that I've had.

IMO, all Corvette's look kinda like they've got a 4x4 ride height with the notable exception of some dedicated track cars and others that are at an impossibly low ride height. You can't get away with that sort of setup on a street car without being all over the bumpstops and scraping on everything (assuming stock spring rates & stock length dampers).

dhowdy

I don't know... I just like fiddling... I also have very little total seat time and this is only car I have competitive driving experience in, so mostly I just drive it for a while until someone else drives it and says something is wrong. It does look a bit silly though, haven't taken real measurements. I'll just leave it alone for now...

Xian

No worries. If you need ride height measurements, I can take them and post them up.

FWIW, I think the ride height on mine "looks" higher than most cars that I've owned but it's (apparently) in the right place. I've got relatively little seat time in mine thus far but prior experience in club racing/autox.

Painrace

You get the lowest CG you can with the proper corner weight and alignment and let the ride height be what it is, If you want to be fast!

Jim

strano@stranoparts.com

Because they car is faster and IMHO easier to drive with a full tank of fuel. And yes power down is no small part of that.

However, I know the 'internet' says I'm nuts for it. So, well I'm nuts.

I've full, dead empty, in the middle, etc. I tend to.... oh, do "ok" speed wise and I'm already the biggest heaviest guy in the class. Add fuel and the car is that much heavier, doesn't seem to hurt me much. If was faster with less fuel I'd do it. I'm not.

Cornering with 1/2 the predicted fuel load, why? With driver makes sense, you don't corner with 1/2 the driver's weight in the car do you?

Xian

If you mean visually how the car looks from corner to corner, yeah... that's not important. That doesn't mean that you can ignore ride height completely as you've got to make sure you're as low as you can without running out of travel.

Cool deal. I'd had someone at Dixie a couple weeks ago ask me if I was "running a full take like Sam"... and I obviously wasn't. I figured that you weren't the type to run the fuel if there wasn't an advantage but wondered what the advantage was.

dhowdy

Some of my fastest laps are with passengers. I'm willing to believe a full tank could lead to faster laps.

96CollectorSport

I think it depends on what you are using the car for, in your case - autocross you're done in less than 90 seconds.
When I set a car up for NASA races I like to set it up with around 1/2 tank so that the balance doesn't change too much through out the race. From dead empty to full I see around 1/4" difference in ride height, if I set up with 1/2 tank I'm only changing 1/8" lower at the start of the race to 1/8" higher by the end.
The way I see it the cars only going to full for the first 1/4 of the race - and you aren't going to be empty for very long. If I set it up with 1/2 tank I should be in the sweet spot longer.

If I were setting the car up just for TT it would be a different story, plus we always have to worry about those pesky scales after races and TT sessions.