632C2

The car is a 1967 Corvette convertible.

All of the runs were made with the factory 1967 tri-power intake manifold, factory cast iron exhaust manifolds, a custom fabricated 3” exhaust system, all accessories connected (including clutch fan), and power steering.

Here are the numbers from the DynoJet:
STD: 671.05 rwhp / 633.45 rwtq
SAE: 652.77 rwhp / 616.20 rwtq
Uncorrected: 671.87 rwhp / 634.23 rwtq

Some of my friends want to know what that equates to in flywheel horsepower. I hear a lot of people talk about 15%-20% for manual transmission cars.

If you take 15% the numbers become the following:
STD: 789.47 flywheel hp / 745.24 flywheel tq
SAE: 767.96 flywheel hp / 724.94 flywheel tq
Uncorrected: 790.43 flywheel hp / 746.15 flywheel tq

If you take 20% the numbers become the following:
STD: 838.81 flywheel hp / 791.81 flywheel tq
SAE: 815.96 flywheel hp / 770.25 flywheel tq
Uncorrected: 839.84 flywheel hp / 792.79 flywheel tq

There are some people on this forum that insist Corvettes eat up well over 20% due to the independent rear axle.

For any purists out there, I am not trying to pass the car off as an original 435 hp 427 Corvette. It is a 327 car pure and simple. I will freely admit this to anyone who asks. The more I thought about trying to make a tri-power setup produce big numbers, the more I wanted the challenge. Making this combination run with factory exhaust manifolds just added to the challenge.

My goal with this combination is to have it appear factory correct under the hood. I also happen to have a 1967 Corvette coupe with a 632" motor that looks nothing like stock under the hood. I wanted to do something different this time. I have taken a great deal of time trying to make things appear stock. Most everything for this conversion was purchased from Paragon Corvette Reproductions.

This car originally came with a 350 hp 327. I put a 383” motor in it around January of 2006. With cast iron exhaust manifolds and 2-1/2” exhaust, that motor made 416.47 rwhp / 430.4 rwtq and went 11.93 at 114.99 mph in the quarter. (BTW, the 383” motor is for sale.)

The gold color you see on the top of the exhaust manifolds are a result of the exhaust manifold paint I purchased from Paragon. I painted the entire exhaust manifold with this product. It starts out gold and then as they heat up they change to a cast iron color. Since the temperature of the exhaust manifold is lower the closer you are to the exhaust flange of the head, the longer it will take to change colors.

The motor consists of the following: Chevrolet Bowtie block, Dart *highly disguised* 335 CNC heads, Jesel valvetrain, Mike Jones solid roller cam, Isky EZX roller lifters and valve springs, BRC crank, Howards I-Beam rods, J&E pistons, Total Seal rings, Clevite 77 bearings, Dan Olson oil pan, Holley fuel pump, and a trio of *SPECIAL* Holley 2-barrel carburetors.

I have made 52 DynoJet runs to get to this point. My first run was on October 20th, 2011 and the final run was on November 20th, 2011. I have tried everything within reason including moving the cam timing 4 separate times. I am not talking about ignition timing here. Anyone who has moved the cam timing on a motor that doesn’t have a belt drive while the motor is in the car can attest to the amount of work it requires. The entire front end of the motor has to come off every time.

I'm sure I left a bunch of stuff out but this is a start. I have a friend that owns a machine shop that bored, torque plate honed, align-honed, and decked the block to my specifications. He also balanced the rotating assembly. Everything else was done by me. This includes the assembly and necessary massaging of the components in the motor. For instance, since I now have a mill and a lathe, I was able to flycut the pistons and machine my own pushrods. I also made significant modifications to the oil pan and fabricated the 3" exhaust system including making my own 'X' pipe. The exhaust system consists of (2) DynoMax bullet mufflers and (2) DynoMax Ultra Flo oval mufflers run in series.

One last thing. I will be drag racing this car this spring. (Sorry for the long-winded post.)

Steve

62Jeff

Ummmmm, holy chit?!?!

That's amazing work.

provette67

Wow great job

5thvet

Very impressive~~~~~~~

Kerrmudgeon

What are the specs on the cam? Can't wait to hear it run. Great sleeper until you hear it run I'll bet! What quarter times are you expecting with street tires? Great camo job....

65-StingRay

632C2;

Well you sure "impressed" the hell out of me. That's real healthy power.
Don't worry if you thought it was long winded. I'd like to hear more about that project of yours.

65-StingRay

Plastic Pig

Cool project. Looking forward to seeing it in action. Don't forget the vids.

claysmoker

Very nice.

What are you doing for a rear end that will live?

provette67

you had better buy stock in a tire company it looks like you are going to need it

632C2

Thanks guys!

Steve

632C2

The cam specs are 254*/258* @ .050", .701"/.700", 114 LSA. It sounds as close to the stock cam in a 435 hp 427 as myself and a couple of friends can remember. Nothing radical in any way, shape, or form. This thing is shockingly smooth.

I will be running Mickey Thompson DOT radials. Hopefully they will get the job done.

Thanks again.

Steve

632C2

Between this thread and the one in the C3 section, you will probably get all the info you would like.

Thank you for the kind words.

Steve

632C2

Here is a link that will answer your question.

http://forums.corvetteforum.com/c3-t...onversion.html

Steve

Donny Brass

very well done.....

I love a lot of power out of a stock looking car

632C2

Thanks, Donny. My inspiration for this car was the F.A.S.T. cars. I know you know something about them.

I just wish I knew more details about their cars. I lurk on their forum trying to glean information but to no avail.

Steve

claysmoker

Thanks, saw that thread before but didn't put it together with you. That will hold the HP OK. Is the car tubbed or do you have flares to contain the tires you'll need?

vetrod62

Wow, great numbers. It has been a long time since we have talked and have not seen your posts on the c1 forum. I am looking forward to you setting some new records at F.A.S.T. racing.

BTW, if you are going to use the TKO-600 trans as in the linked post, it will cost you big time in ET. I dumped mine after 3 years of racing, and that included mastering the 2-3 high speed/fast shift. I picked up .3 seconds with a M-22W. Jim

babbah

What makes the carbs "special"?

BarryK

well, they aren't as smart as the other carbs, they have to wear protective helmuts and large soled shoes, and they ride the little school bus.....

65tripleblack

Congratulations, your hard work has paid off! 1.416 HP/cu-in is stout indeed. I don't know that the cast manifolds are hurting you, especially if you had them extrude honed by Brzizinski. The tri-power setup is killing you. Ever thought about "cloning" the L72 instead?

The very large intake ports hurt the bottom/midrange torque.........and it shows. Good for peak power number and pushes the peak RPM further up by a few hundred.

Now, if you can only "disguise" mechanical front/rear carbs, you'd lose that big dip around 3150.