I've had my 1981 Corvette for about 4 years now. The old 350, 190 hp stock
engine has about 87,000 miles on it, and I was thinking about modifying it
to get more horsepower. So, I took it down to the chevy dealership for them
to check it out, and they tell me I have something called "blow by" with
major oil problems that can't be fixed. They said I will need a new engine,
so I went down to the local speed shop, and I'm getting them to build me a
new 383 with over 550 horsepower.
I was at school today, and I realized that going from 190hp to 550 is quite a good jump, considering my car is the most powerful car I've ever driven. I'm kinda worried about all the parts in the car like the transmission (wich I think is a 400, but it could be a 350, does anyone know what type of transmission they put on an 81 vette?), the driveshaft, axle, or any other part that has direct relation to the engine, will they be able to handle that much power? I'll have to drive it every day to school, and it's my only ride, but I was wanting to take it down to the local drag strip every once in a while to test it out.
What I really want to know is how hard can I push it without having to worry about breaking something? I've gotten pretty used to flooring it with the old 190hp, but I'm pretty sure flooring it from a dead stop with 550hp will surely break something. I was wondering if anyone could help me out, and tell me what I should, and shouldn't do with this new engine? How far can I push it, and if I must, what parts of the car should I replace to handle this much horsepower? I'm very low on money right now, mostly because of the new engine, so please keep it small. I was also thinking about getting new tires on it soon, so what type would you reccomend with this new engine? Thanks for all your help!
Can't help you at all with any info or specs for your vette, but I can give you some moral support. I'm going through the same thing with my Stealth. Every person I talk to has something different to say. The best advice I can give you, is use common sense (wich most mechanics lack). Any reputable "speed shop" should explain to you some of the changes you will see in your car and discuss other mods to help handle the horses before you build the new engine. With all stock parts I wouldn't push it too far. Any tunning you do will be expensive, that's a fact of life, but any tunner knows that you do one thing at a time, and change it if the desired effect isn't what was expected. Tunning is a very slow and tedius procces. First thing I would do is break the engine in (SOFT AND SLOWLY) and see if it has daily drivability first. Don't go over 60MPH or try to accelerate faster than neccesary untill at LEAST 500mi. Second would be extra sturdy struts and braces front and back. Then of corse the stock clutch has got to go, even if it is equiped for that amount of HP, the wear and tear on it from previous owners or you can mean disaster. I would go with an "center force" clutch designed for your special application. Do you know if your carburator and fuel pump can out-put enough for the new engine?? My best advice is to get ahold of others (vintage vette owners) whom have had engine swaps, they know their cars better than most of the Macanics that work on them. They can give you specifics that are really neccesary for any "in-depth and comprehensive" tunning.
Do yourself a favor and go through the transmission while the engine is out. I would say you will surely kill it without some attention. The rest of the driveline is pretty stout although you probably need two new stub axles in the back as the dif wears tends to wear out the end of the axle where the snap rings go on.
you have the turbo 350 tranny, its a good tranny but will not handle 550 horse in stock trim, actully almost no stock tranny will, I would suggest going to PA performance lookingfor a good tranny
You do have a th350 and it definetly will not handle the hp. Niether
your universal joints on your driveshaft. Most likely you differential
would'nt quiet make it either. and these are just a few of the probs
that you will encounter without haveing the car properly preped. Your
talking thousands. I hope this helps you.
Amen brotha nizzo