Hey everyone,
First of all I want to thank everyone in advance for all the help I just bought a 76 with the L-48 engine with 128,000 miles and I need all the help I can get. My mech. skills aren’t the greatest but I'm willing to learn and bear with me if I ask a lot of dumb or amateur-like questions. I've been browsing the forum and have picked up as much general knowledge as possible. I'd like to mod the car to where it has some oomph to it (300-350hp?) and still maintain it as a daily driver and get somewhat decent gas mileage. I noticed that a lot of people are converting to the LS1 engine with a T-56 tranny which would seem to be the best of both worlds when it comes to power and fuel efficiency but it seems way above my skill level right now.

Well here are my specific questions:

1. Everyone on the forum seems to say the first thing to mod is the exhaust. I live in Ga and to my knowledge there is no inspections. The guy I bought the car from (he also introduced me to this site) said that the car right now is running straight pipes with no cats (I haven’t actually crawled underneath to check out the setup). Is that considered true duals? I have no idea what the diameter of the piping is but I'm assuming I want 2 ½” or 3” right? What would be a good exhaust combination? So far I've heard hooker super comp 3 1/4? with flowmaster 40s mufflers or magnaflow mufflers with an H or X pipe. What about chambered mufflers from a company called sweet thunder? Are those worth the money?

2. How long can a L-48 block last? Mine already has 128,000 miles how many more miles do you think I can get out of it. I don't want to start bolting on stuff and eventually have to replace the block. Would I be better off in just buying a crate motor?

Again, I'm sorry for all the questions and I'm sorry to ask the same questions every newbie seems to ask.

Thanks,
Yuchen

 

Sometimes crate motors are a better deal then bolting stuff on to an old motor. Getting You can get a motor in that HP range that will be very streetable.

An overdrive will definitely save you some gas money. If you want the best of both worlds, saving some money in the process, bump up your rear end ratio to at least 3.70. You might want to get the OD tranny first though.

 

WELCOME

Have you ever pulled a dash before??
come help me out on my other thread

 

Welcome to the forum and Corvette ownership. This is one good place to get advice. Just beware that you need to verify anything you see coming back at ya.

So, now for the free advice. If you're looking for over 300 hp, it will probably cost you $2K+, whether you rebuild yours or go the crate motor route. If you're not fussy about numbers matching, going the crate motor route is the cleanest and quickest way to go.

Yes, true duals seem to be the favorite quick bump in power, but it won't snap your neck. I think some if it is imagined, because of the noticeable increase in noise, when dropping the cat, and the pulsing of the separated cylinder banks.

Happy motoring!

 

From one new owner to another- welcome to the wonderful world of the all-american dream machine. Given the fact that your bicentenial year C-3 just turned 30, and mine 27, I think we found the right place to seek help and advice. I have gained a great deal of courage while reading this forum nightly. Good luck!

 

If your block is not cracked or otherwise damaged, it could last many, many miles. I've got more than 300,000 miles on mine, and many folks get 500,000 miles or more from blocks.

 

Welcome to the insanity!

Lots of luck w/the new money pit!

 

I say go with a crate motor with that many miles instead of tearing the whole thing apart. Pull one out drop the other one in.
"Wham Bamm Thank You Maam" deal
Welcome to the forum

 

WELCOME NEWBIE DUDE!!!
I'll be a one year owner of a 76 this coming May....these guys are great with advise and the comradery is outstanding!!
My 2 cents?....make sure she can breath well on the back side...2.5 or 3 inch...I have 99,983 on my vette and aside from valve guide seals needing replacement, I'm gonna keep her with the stock engine...IMO, it's a privilege just to drive her, nice and easy, like taking your grandmother for a walk...if I want to go fast, I beat on my 2000 Mustang
Have fun, I KNOW you'll enjoy the 76

 

Thanks for all the advice! You guys are great!

 

A word of encouragement, if you are thinking of keeping the old block. When I rebuilt mine at 106K miles, the factory honing cross hatching was still visible on the cylinder walls. I bored it out anyway.....


Z-man is right. Those SBC blocks will go a long way if not mis-treated.