Neil was also working with Craig Breedlove on a 1000mph LSR car, which was to be driven by another college friend of mine (who holds the record for a semi truck tractor...who knew there even was such a record?). Only a lack of funding has prevented that project from going forward. I know another guy from college who went to engineer for the Hall/VDS Indycar team. Another friend went on to work in Mission Control at NASA for years, after he spent several years in a prominent speed shop running their dyno and modifying cars in very badass ways, all while earning a physics degree. I know all these cool people from back in the day, but none of it rubbed off on me!

 

Ha ha...that ain't true.

 

Thank you. Nice explain

 

I just ordered the VanSteel Full Race Double Adjustable Coil Over Kit from VetteMods (Which shipped Direct from VanSteel with Ekler's Paperwork) and it came with:
Hyperco Springs:
Front 186A0800 The "A" stands for 2.5" I.D. 800 is the spring Rate.
Rear 186A0600

Save yourself nearly $300 dollars and just deal with VanSteel. One thing I did note is that VanSteel has suggested spring rates for Street(400/350), and Aggressive Street(500/425), but prefer a phone call for Race setups. Ordering thru VetteMods I did not get to choose my spring rates so I figured I better call and find out where I should be. Had an Amazing conversation with Paul "The Old Guy" (His words not mine) about my car(Stock '92 Coupe LT1 6speed) and how I planned to use it. I'm looking for a track oriented car I can drive to and from the event. He said this was a good baseline. While looking at their site and your pictures I noticed quite a few parts I don't have. I have the time just need to find the $$$.

Since I will already be under there I am looking at adding:
Front Camber brace
Front and Rear Heim Sway bar links
T-Arm/Toe Rod/Strut Rod Combo Kit w/Racing Heims

Best take away from my conversation with Paul was knowing what I planned to do about Tires, wheels, and Alignment. Having his parts allows me to adjust to or get the most out of what I have actually touching the road.

l98tpi I appreciate you taking the time to post pictures and videos of your C4 journey, it inspires more Forum Lurkers than you will ever know.

 

FWIW, in the interest of working with your budget, I'd prioritize the Strut Rod and toe link with heim joints at the top of the list, followed by the trailing arms, followed by the sway bar links, and last (and least) the camber brace. The strut rod is super important because the stock camber adjuster has a bad habit of slipping and you lose your camber. It also allows more negative camber. It's vital, IMO. In 4.5 years of autocrossing a well sorted C4, I never felt compelled to swap the poly-bushed sway bar end links with expensive heim-jointed ones. I had a camber brace sitting in the garage and didn't use it. It is heavy and makes front engine service harder, and I had no issue with loss of front-end camber.

PS - Tom, I got the club to update my article with the change on coil springs being torsion springs, but I forgot to update the C3 rear suspension. D'oh! It may have to wait because the webmaster is offline due to health issues (not covid, but not good).

 

I had been busy later last year after I went back and made some changes and didn't post some changes I made. After a few runs once my C6 went down again, I was back in the C4 and felt there was just a little too much body roll going on. So, I went back to recalculate my rates and look at the suspension frequencies. Once completed, I came up with 650lb front and 750lb rear. Installed those rates and got two runs and transmission pump failed. But those two runs felt great. Times were competitive too and I was running on two year old Rival S 1.0's. Im excited to get to run this year whenever we finally get to. I got new Yokohama Advan A052's now, so should really get a good test with the new springs. Ill try to update once I finally get to run.

 

So I did the EMRracing coilover conversion and VanSteel Camber Brace on my C4 Corvette with 400 Front and 300 Rear springs, but often felt like the 300lb springs in the rear seamed to wash out in turns during autox events, like trying to compete with a Hay Wagon. Also, too soft for my 383 SBC TPI motor, which was leaving out of the hole almost raising front wheels on a wheelie - alarming me that rear end was bottoming out in travel - so I'm switching rear out and trying a 400/400 spring setup. What ride heights have you guys found effective on a streetable C4 corvette, without scraping of front wheels turning and front spoiler issues on driveways etc.? And also wheel and tire combo sizes? I read between 26.5" - 27.5" ride height to fender lip is recommended for shock travel on the streetable C4 Corvette - but I don't like all the gap above tires in wheel wells!!

( I'm running 245/17" front wheels and 285/18" rear C6 wheels and Bridgestone Potenza RE-71RS tires with the C5 Big Brake Conv in front with different hubs which allow clearance for turning)

Some added info for heavy cornering
https://grassrootsmotorsports.com/ar...orner-weights/

 

So, with changing the rear springs out to the new QA1-HT10400 (High Travel springs) I get roughly 26" in front ride height and my rear is now at 26.500" ride height - which equates to roughly 2 finger high clearance between top of tires and wheel wells front and rear using the C6 rim and tire combo listed in thread above. Tomorrow when it isn't raining outside, I will go out and bang some gears to test it out!

 

I don't really know what you mean by the rear "washing out" in turns. However if you mean the real breaking loose - i.e. oversteer - then you would not want to go with stiffer rates in back, but rather stiffer in front. However, it's also very possibly the shock valving that is too stiff in rebound or compression or both. I don't know for sure which shocks the EM coilovers are built on, but it doesn't look like they're adjustable, so you may be out of luck. Also, I don't think the EM kit does anything to relocate front or rear shocks, so you may be experiencing contact between the rear spring or spring perch. If so, that might be causing a sudden spike in wheel rate, which would cause a sudden oversteer situation.

 

Being as straight forward as I can; you have to make a decision if you’re main goal is to have the best handling car you can or if your goal is to have a nice look for the street and Cars N Coffee. I’ve seen a few mentions of ride height; that’s a start point but the best handling will be achieved by corner balancing the car. If you look real close at competitive AutoX or Track cars you’ll see different heights or gaps between tire and fender side to side and front to back.
Also, there are different ways to set up a car suspension with spring rates and you can adjust handling with spring rates or with compression and rebound settings or with changes in the anti roll bars.