My 81 has the 5.7L V8 (Not sure if this is the L48 or the L82, don't really know my stuff too well). But I was looking into putting some engine components into my car to bring it up to around 300 Horsepower, that's my main goal. I think the stock Horsepower is around 220?(Correct me I'm wrong). Is there a way to tack on extra horsepower without huge modifications (Such as cutting the endgine hood panel, etc)
Thanks in advance :D

 

The first thing i would do is exhaust,then a cam.You can do alot with out having to go to cut the hood and even then you can get a custom hood thats raised.Oh and welcome to the forum. :thumbs:


[Modified by patsnitrovette, 8:17 PM 4/20/2004]

 

Both the L48 and L82 are both 5.7L V8s, just so you know. I have a '79 L82 which had 225 stock horses I believe. You're in exactly the same situation as I am... I'd like to acheive around 300 horses.

What I'm doing is scrapping the manifolds and adding headers, going to true dual exhaust, bolting on a new intake manifold (Edelbrock) and will go with a high flow air filter. Internally I'm going with a mild cam and keeping everything else pretty much stock. Eventually, I'll swap out the carb as well. That should (hopefully) get me in the neighborhood of 300.

Those are just my thoughts, but I think that's the least you're going to need to do to get to 300. A new set of heads will without a doubt put you where you want to be, and them some, but it will also cost you.

Best of luck.

 

If it were MY nickel, I'd swap some aluminum heads on when I did the cam/header swap. Air flow is where it's at and don't forget that HP is just math. Torque is what you want. Too often, cam swaps are made for top-end HP without regard to the compression ratio that the engine needs. The end result is a nice rumpity idle, but NO power! Really, you ought to consider either smaller-chamber aluminum heads to match the CR to your cam choice, or go even further with domed pistons to bump the CR up.

But this is starting to look like the proverbial "huge modifications" isn't it?

Sorry. I'll shut up now...

 

Stock horsepower is 190hp. The 81 has the "L81" engine. 8.2:1 compression. Healthy for a turbo or blower setup, but not for an NA engine. Easy mods to raise your horsepower are: 1. Get a custom true dual exhaust made. I just did this recently, and felt a huge bump in performance, but due to my engine combo, I may have gained a few more ponies then you may. If you need to keep your catalytic convertor, at least replace it. It's probably nicely gummed up. If ya don't need it, well, need I say more? 2. Raise the compression ratio. Good flowing heads, or just getting your stock heads reworked and shaved can accomplish this. 3. Almost any camshaft other then stock would be a 110% improvement in power if you have the other mechanical parts to help it work properly. ie. Intake manifold, headers, exhaust, etc... 4. Change your differential gears. I feel your pain man, I have an 81 as well, and the stock 2.87's are DOGS off the line. If I'm not mistaken, the largest gear that you can fit into an 81's rear end is a 3.90... Perhaps too drastic for some with a stock 3 speed, but if you upgrade to a 4 speed auto, or a 5 speed manual, this is a good mod. 5. Last but not least, just spend the $1000 or so and get a 383 stroker kit. I promised you'll be impressed. If you do all these things together, you'll have a very healthy running vette. Of course if these mods are done together, you will probably require a bit beefier carb setup to meet the extra needs for fuel/air. Just think of it like this. An engine is nothing more then an air pump. How can you make your air pump run more efficiently?

 

racing stripe, spoiler, and lots of stickers :leaving: :leaving: :party: :party: :party:

 

Definately. More stickers the better. And make sure they are a good variety and extra colorful. Figure the good ones will yield anywhere from 5-8 hp depending on placement and tackiness.

 

ohh yeah and make sure that u get one of those window stickers that goes across the top of the front window in a color that doesn't even match to give you that seemless chopped look.