I haven’t posted in a good while- nothing really to post!
Just to refresh, I modified my 68 Corvette into basically a track car (1/4 mile and standing mile) in 2018 and raced in many events until late 2022. The car has all ride tech suspension with coil overs, Willwood 4 wheel disks, built rear end and we were racing it with a 632 and built 4L80 trans with brake. We ran a Holley super sniper set up and E85 fuel. I had a 185 Nitrous shot, but only used it once. The car ran consistent 9.50’s in the quarter and we retired the car when we ran 203 mph in the Texas mile in October of 2022. Since the car was only teched for 199.9, no more mile races without major modifications. Due to this and Raceway Park in Baytown, TX being closed we retired the car, sold the race drivetrain and started building a chassis car for standing mile and drag & drive events.
It hurt my heart to see the vette covered in dust in our shop, but didn’t have time to dedicate to the 68.
I pretty much completed the race car late last year ( as much as you can) and committed to getting the sweet vette back on the street. The goal is a nice driver.
I bought a BPE 540 and Hayes 4L80 transmission. We are using the 8 injector sniper, with a Holley Terminator X ecu to control motor and transmission. The motor and transmission are currently in the car. We had to modify one header tube (the 632 was a tall deck with raised exhaust ports). We are hoping to be back on the streets in mid April.
Life is not complete without a C3 cruiser!!!

 

Great to hear. As an owner of my own '68, I completely agree about having a cruiser. Good luck with the car!

 

203 mph in a Stingray sounds wild.

 

You are definitely on another level . Very impressive. Would love to see pics and video links of you crushing the 1/4 and standing mile in it.

 

We the few, the lucky ones, the ones who own one of the greatest Corvettes of all times, the 1968 Corvette, salute you for being brave enough to take a C3 up to 200 mph. That takes some huevos to go that fast in a car not designed to do that! Congratulations!!

The BIG question I have is How did you hold the front end down while going that fast? The extra engine size/weight would help a bit but what else did you have to do to get past the lifting force? It scares me when the wheels are not solidly on the ground. I purposely stay below 130 mph because of that lifting sensation.

200 miles per hour is blazing fast and with the lifting shape of the nose of the C3, I would really like to know how you managed to to keep the directional control above 130 mph or so.

Did you run with the 1968 Differential or was it replaced to be able to achieve the speeds you were trying for? After reading some of Gary's posts it seems that the 1968 differential is not a great thing for high horsepower applications.

 

Man you’re not kidding. That car has to be extensively modified but still I can’t image 200 in a ‘68.
I don’t doubt you did it but dam !!!
My ‘68 has the L68 thats got a bit more hp with the rebuild but I’m sure its no where close to what it takes to run 9.5’s in the quarter. Still when I punch it the front raises up and stays up till I let off. When it had the 3.08 gears I had it up to 125 with the nose up and it hadn’t stopped pulling hard. I ran out of nerve before it ran out of power. It was kinda terrifying as the front felt very light at that speed . To think that guys buried the speedo back in the day on bias ply tires is nuts. Hitting over 200 even on the best of tires is equally nuts.
I have a ‘73 Rallye Charger I’ve modded and lowered with more than twice the original spring rate. I’ve had that up to 135 and it sat like a rock compared to the vet. It’s only about 400lbs heavier too. I’m sure the Vette is a lot faster but at speed the Charger is more confidence inspiring.

 

That feeling of 'disconnection' with the front-end of my '68 is not a pleasant 'experience', certainly on OEM sized wheels and tyres - surprising using 18's with same height but low profile rubber seems to help that 'feeling' significantly. As for 200 mph with a 3.08 rear end and Muncie 'box......no way without some form of overdrive transmission unless you can use seriously tall rear tyres I'm guessing.

 

5 degrees positive caster would help stability quite a lot dropping the front in at least an inch or inch and a half is what Chevy recommended to raise these things back in the day that helps with stability as well on the nose