Hey peeps, currently own a nice 1986 greenwood corvette. I want a second vette but have a dilemma and am not sure if i want to step up and get a good looking c3 with a decent Big Block or a C5 with a supercharged LS2 to satisfy my craving for neck breaking acceleration and cornering. May I ask questions about C3's

I know C3's were not designed to have a high top speed or to be perfect around corners. But, with modern add-ons, are there any around? Are there any trannys and add ons that would permit C3's to be decent around corners and stay stable at higher speeds (150-160MPH) without having to pay crazy amounts for one with drag components?

Thing is I love the looks and the style of C3's but I've driven a couple and despite the good shape they can be in, find them quite shaky at 80mph and unless one has a 383 or a big block, find them pretty eh...darn um...slow

So, lets say, I want one that can outperform my non-stock C4 which accelerates for 0-60 just under or around 5 seconds and can hit higher speeds confidently. What kind of cash would I be looking at spending on such a C3?

Let me put it this way, the competition to my interest on a C3 is this rich dude moving out of the country, selling a very nice 1999 C5 with a supercharged Ls2 pushing over 700 horses for 25 grand canadian. Considering I love the looks and wildness of a C3 much more, although I'd never expect a C3 to have the same performance values of a more modern car, what kind of performance could I get from a C3 for the same price? thanks!

 

As your focus is clearly on performance, get the latest Corvette you can afford. No comparison, the latest is going to be the "Best Vette Yet".

C2/C3 technology is from the 1950s. You have got to throw a LOT of money at a C3 to get it to perform like a C5/C6.

That 1999 is a 14 year old car, you might want to look around a bit given the C7 is on the horizon and folks are looking to upgrade.

 

Based off the performance you are after, go with the C5.

 

Super,

You will be disappointed with the C3s unless you dump in 20k+.

 

A c3 with overdrive and a big block is your only hope of being satisfied comparing to a c5 with a supercharge. After that you'll beat your head against the wall trying to balance the tires to run smooth at all speeds up and over 80mph but it is doable!

 

excellent advice from everyone

 

From a logical point of view, I agree with the above posts. That being said, I would love to get a C3 and put in some serious handling/ power upgrades.
$9,000 will get you a solid C3. If your budget is $25,000, that leaves $16 K for upgrades. If you do your own wrenching, I bet you could set it up very nicely.

 

Supercharge a C3

 

Mine will go 60mph in first gear, no power adders but it cost me quite a bit

I was told by a shop owner up here that builds s/c C5-C6 that he puts a pulley on it to get the numbers on his dyno for his customer then puts another pulley on it so he can actually drive it around on the street, I don't make this stuff up that's what he said because I asked him.

 

You can make a C3 as fast as anything else out there in a straight line, but the high speed handling will not be comparable to a C5 or C6. Even putting a custom $$$$$$ tube frame under a C3 with C4/5/6 suspension doesn't overcome the aerodynamic deficiencies of the C3 bodystyle.

Buy a C5, I think it is more what you are looking for.

 

Late ones definitely for more speed cheaper, but C3 shaky at 80?

That's a little odd.....my '73 underwent a suspension rebuild (springs/bushings/Bilstein shocks) about 5 years ago and feels pretty stable at 80. I would prefer some kind of upgrade rack and pinon steering, but it's just money. 80 with 308s is about 3,000, so a 5th higher gear would make it a lot more comfortable in high speed cruising. Actually, as I recall Duntov said the in some interview that the suspension was designed for sustained 80 - 120mph. In the movie Le Mans with Steve McQueen (much of which was filmed during an actual race) there are scenes which include racing L88s which reportedly ran as much as 170....and that was definitely on old technology. Seems to me with gearing and modern technology applied to the suspension, it'd be possible to create a reasonably stable high speed car. How did the L88s stay on the ground in the 60s at speed?

Beside, I think a cool C3 will always garner more admiration than a one of a zillion late models. But it's going to take some bucks.

Maybe a resto mod. There's a 'vette guy here in Plano that can provide a completely new chassis and late model running gear with an LS motor of your choice which will take a C3 body and interior. Big bucks, though. I was in there the other day and took a pic of a frame, with late model disk brake running gear they had just gotten in for a C2, as I recall.

 

Mine is stable at 120mph it's the front air dam and rear spoiler they removed for most of the 70's that make them unstable at speed allowing too much air under the car. My Cuda was scary at 120mph but I could drink a coffee in my '80 at that speed.

 

I had a 99 and it was far superior to the C3 I bought using the C5 money. But C5 and C6 cars are a dime a dozen. I like the looks and the feel of a C3.

 

So go talk to him. Take your check book. Instant pocket rocket with no further mods. Wear your HANS device.

 

If your up here in Toronto, go see my friend Mike at Active Engines he'll tell you what to do, I already know what he will say. Tell him Wayne sent you, he is in Oakville at Winston Churchill and Lakeshore

 

You can buy a C-3 minus engine and trans if you look for cheaper, then drop in an alum ls based engine/OD trans and do the tire/wheel and brake upgrades. I am sure you would be satisfied with a lightweight combo like this. Maybe someone can say what handling difference their is between an upgraded C3 and "stock" C4? Is their any advantage to up keep of parts one way or the other?

 

Often wished I would have kept my 93 & SC'd it, but it's gone & I have the 79. Oh well, it's still a Vette & better than 99% of what's out there.

 

Horsepower is the easiest part of the equation, as long as you've the funds. Just build and/or install whatever floats your boat, whether that be an all aluminum BBC, big inch SBC or LSx. (I'd caution building a large amount more torque/power than the rear tires can handle if AX/RR type performance means more to you than 1/4 mile ET's.)

The transmission is only a matter of making the selection which best matches your torque curve, rear gear and purposes, again if you have the money. For serious AX/RR type driving, best to opt for a manual (on-track based opinion), and if you're bucks up you could even think about a sequential no-lift-shift setup. Oh, and while we're on the topic of driveline, be prepared to invest a good bit in your diff if you expect it to survive regular abuse behing a stout mill. IMOE you don't have to be on slicks or dumping the clutch at insane revs to break a 10-bolt.

Where simply throwing money at things won't fully pay off unless you really know what you're doing is in improving C3 handling. First order of business is to install the largest (footprint), stickiest, modern, high-performance tires practical, and put the car on a weight loss diet (without compromising safety). Next, study up on the C3 road-racing recommendations found in the Chevy Power book Corvette chassis section, and do everything you can with them. Beyond that, there are a number of further mods and tricks that can put your shark in the G club, not the least of which would be eliminating or at least minimizing the adverse effects of inherent C2/C3 rear toe-steer. In any event, the more serious you get about this, the less likely you'll find everything you need bundled into an off-the-shelf kit.

Aero wise, fastbacks ('78 & up) slip thru the air a bit easier than do earlier C3's. Also, installing a Pace Car style aero package (front dam and rear spoiler) on a '78-79 reduces drag by a further ~15%, and definitely helps stabilize high speed characteristics. (The factory PC dam will need additional bracing for much high-speed driving, BTW.) '80-82's are almost certainly the slipperiest C3's, and already have integral dam and spoiler, but not sure how they compare to '78-79 w/PC kit on lift/downforce. Contrary to common myth, the C3 body can be safely pushed well beyond 120. You should readily find plenty of discussion on C3 aero here in C3 Tech/Performance.

FWIW, I had a '92 6-speed LT1 (below) which I ordered new with everything except the hardtop and luggage rack (), and it handled very well, but having gotten my '78 chassis fairly well sorted over time I always left the C4 to cruising and looking pretty, preferring to do all my "spirited" driving in the shark. Nope, not anywhere near done modding it...

There's much more to all of this, of course, and if your not up to doing a lot of work to get there it will be much easier to just buy a later gen Corvette. In any event, bear in mind that handling performance and ride comfort are pretty much at opposite ends of the spectrum here, so anything you do in favor of either will necessarily compromise the other. BOTTOM LINE: Which ever you might prefer, the best solution is obviously to go with both choices.

Hope something I've offered helps your decision.





Had the aero kit on hand before the car was even built.

 

A "hot rod" C3 will never be the equal to a "hot rod" C5. Just keep in mind "hot rods" are just that "hot rods". Unless they are well sorted out they can be temperamental and will always be some type of compromise. Forgetting about bragging rights I'll throw a 3rd choise into the mix. How about a C5 Z06 for about the same money? There are plenty around. Many of them low milage and still belonging to the original owners. Those cars were pretty well sorted out by GM. No drama. Very high fun factor and reliable. Just thinking out loud.

 

I Have a modified C3 383, 5 sp with a bunch of good stuff, and a base model stone bone stock C5 with a 6 speed trans. I have a ton of fun with both cars but thay are and drive entirely different.

As for performance IF and only IF I can get the the C3 to hook, it is quicker than the C5 in a straight line until the front end gets light. Other than that it has no chance in any other aspect against the C5. Don't get me wrong I love the C3 for lots of reasons but if overall performance, cornering and also important, braking is your goal, the C3 would have to be heavily modified to have chance.

TheSkunkWorks post has it exactly right, it can be done. But I continue to work on the C3 and I'm not convinced you could get there (including 700hp) for 25g's total.

BTW, if I want to get a passangers attention, we take the C3, its just nasty, they tend to hang on tighter, it just feels like it is kickin serious azz. And tires are cheaper!