1Cerberus4u

Hey All,

I have a 65 and want to set it up for more aggressive street/track day suspension. Car presently has FG mono spring in front, 7 leaf in back, 1 1/8's bar in front, 3/4 in back and Bilstein sports.

I am interested in;

Lowered ride height but still within suspension operating specs - What should ride height be?
What mono spring rates are people running
For giggles, what coil over springs are people running (rates and lengths)
What shocks do you like/
Sway Bar sizes
Alignment specs?

Thanks!

Gordy M

Back in the day when I was autocrossing my 64 a fellow club member told me to use the 66 big block with air front spring as it was the shortest available and had larger coils. That lowered my F40 front suspension almost 5/8". For the rear, if keeping the leaf springs, get the 69+ control arm and it will lower the rear about 1/2", then get grade 8 bolts 8" long for the rear spring. When setting up the suspension, I added 1/2" longer bolts in the front A-arm for more camber. For the street/track set up I was running 2.25 camber front and back and 0 toe in the front. Today there are a lot of other options available plus the L88 suspension set up.

cagotzmann

Well most of your questions it depends.

1. What is your experience level for track days
2. What track are you going to drive on
3. What tires are you running

So if this is new to you.

1. Start with training the guy behind the wheel. There are many good advanced driving schools. eg SpringMountain etc. Local track day instructors.....
2. Drive the car as is. (make sure the car is safe for track days)
3. Start with alignment settings more suited for the track you will be driving.

See below
https://tech.corvettecentral.com/201...ignment-specs/

Then once you have some track day experience check your tires for even tire wear. If they are uneven, then adjustment alignment to try and compensate.
Then look at a more aggressive tire. Once you are running with soft tire compounds then the suspension may need tweeking. But this will also depend on how aggressive / experience you are comfortable with.

If you are interested in learning the effects of suspension changes / tires / etc then only make 1 change at a time.

1Cerberus4u

3x defending North Atlantic Road Race Champ. I hold 6 or 7 track records....
I run tracks east of the Mississippi from NH to FL, to Atlanta to Road America, but this will most likely be a hard driving street car with some track days as I have several race cars.
Tire choice are limited due to size by either R rated Hoosiers for track days and high performance street tires

My high water mark is 70 days on track in a single year, but typically about 30-50

I have my own garage what multiple lifts etc...

The guy (and his wife) behind the wheel are experienced.... just that Corvettes are new to us..

Best

Andy

fleming23

It does not sound as though you plan to compete in any series so this is just a fun track day toy?

If that is the case, I would personally recommend visiting any of the big three aftermarket suspensions for these cars and pick the one you feel most comfortable with, and fits your financial plan, unless you are trying to do all the hard work and build your own stuff.

Ridetech - https://www.ridetech.com/application...7-c2-corvette/
VanSteel - https://www.vansteel.com/index.cfm?f...oups&navid=108
Detroit Speed - https://www.detroitspeed.com/1963-19...ont-suspension

I went with Ridetech, and have the entire catalog on my car at this point with their Track1 components and Instinct electronic dampers. Even with their mid-range stuff, and single adjustables, I was turning hundreds of laps at Road Atlanta in my car.

This was 2016. It's a completely different car now.

1Cerberus4u

Hey Flem. Can you share what your ride height is front and rear?

At this point I have the full Van Steel kit on the Black car (65 vert) and the other car Red Car is also a 65 vert, but BB, fibreglass mono in front, 7 leaf in back, 3/4 bars front and rear and kyb gas shocks.

I'm thinking of trying the Koni ACT shocks with a coil over kit - 550lb front springs, 450 rear, (adjustable mid range shock used in Trans Am II racing and a bunch of stock car series), 1 1/8" front bar, 3/4 rear bar and as Gordy said, -2.5 camber all the way around, 1/8 toe out in the front, 0 in the back and all the caster I can get up to 6 degrees and see where that takes me, but I'm jsut spit balling all this..... Its be great to get some insight from all you who have set these cars up.

I'm new to the Vette thing so I'm trying to find what works for folks...

The Black, car, with the full Van Steel, don't plan to change hardware, just work on alignment

Best

Andy

cagotzmann

Well I think you have the suspension thing on the right path, as for brakes whats the plan ?
With my 78 with a full VB&P street slalom setup the weak link is the 360LB rear composite spring. I get too much rear body roll with a 3/4" rear sway bar. Looking at finding a 460lbs rear spring.

As for the brakes my 78 is using factory size rotors 11.75" with wildwood Alum Calipers standard D8 type pads single pin. The best brake pads I have found for the standard corvette calipers are raybestos ST47 pad in the front with ST43 in the rear.
Here are the raybestos specs.
http://racetrackdriving.com/tech/ray...ion-charts.pdf

As for alignment. I have SPC Upper control arms so I can get 6 degree caster and for my 275 40R 18 (Nitto NT01) tires at my track I have ~ 2.8 - 3.2 degree camber so I can get even tire wear with the 275 tires.
These are the upper arms I am using.
https://www.spcalignment.com/compone...AFrom&to=USATo

As for rear toe specs if you will be experiencing high speed braking 100MPH + then 0 rear toe may make the car loose in the rear under hard braking. I have kept the rear toe ~ 3/16 - 1/8 total toe in to prevent the rear from dancing and it may break loose if you lock up the rear brakes ( no ABS ) before the front lock up.

Also you should be able to get front / rear weight close to a 50 / 50 distribution. I am currently @ 800kg (1760lbs) front with 810 kg (1782lbs) rear. total 3542lbs with a full tank of gas (24gal) and me in the car. I am also running a T56 Magnum 6-speed Close ratio with a 3.08 rear so at my local track I get max HP / RPM at the end of the straights. This will vary track to track what works best but I don't like short shifting and prefer to run out the RPMS on as many straights as possible.

Steering has been changed to a r&p because with the factory design setup I had too many hose failures. Buy design the hoses from the power steering to the control value movement requires back & forth movement (not a stationary connection) plus the additional heat hoses would last 4-5 track days.

I also use a standalone TPMS to monitor real time tire pressure
https://www.minderresearch.com/tireminder/

Cooling System is Dewitts Alum with dual fans. GM Serpentine Belt system. Engine is a ZZ383 with a carb & I run a Zeitronix AFR / O2 system to keep the engine running in the proper AFR range.
http://www.zeitronix.com/
The ignition system is a MSD Programmable unit so I can adjust the engine timing based on RPM & a MAP Sensor for vacuum / boost demands.

My next engine will be a LSX setup and go EFI so I can better tune for the day requirements.

The biggest lap time improvements you will get from your car is tires. The wider the better. So if you make additional changes to the suspension allow for 295+ Tires.

1Cerberus4u

Plan for the brakes is to convert to power brakes and upgrade to a wilwood 6 piston front 4 back. Car has 17" wheels on it now,so I'm guessing an 11.75" rotor... I tend to run Performance Friction and I look for pads with a very strong initial bite and then roll off, as that meets my driving style, while the wife likes a pad that does not have quiet as much initial bite as she likes to roll on weight transfer a bit differently... Yes, I do run some PF on the street. A bit noisy, but so aren't the cars..... On my cars with CF brakes, I have not played with different compounds.

This 65 has spc a arms already.

I agree with a bit of toe in on the rear if you have a bit of toe out on the front.

Andy