Motor Upgrades
Thread Starter
6th Gear
Joined: Aug 2021
Posts: 6
Likes: 0
From: Milford,CT
Motor Upgrades
I’m putting a question out there for all of you smarter than me. I have an 81 C3 with stock 350 in it. I’m just looking to get more horsepower without building a race car. Just want a vette that moves like a vette, maybe 300 hp. So far I have added a Quickfuel slayer 600 carb, Edelbrock 2701 intake and Streetfire MSD dizzy. Thinking my next move is mild cam and heads. Problem is, I have no idea what direction to go. Anybody have any ideas about which parts gets me towards my goal? Thanks for any input.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Figure out your budget. That's probably the biggest controlling factor.
I would get rid of any computer controlled stuff for the engine (may require replacing the carb with an earlier year 77-79 are among the best q-jets IMO) and any emissions control equipment as well if your state/area does not require emissions testing.
Then look for Lars' papers on performance tuning your car. Replace the stock exhaust manifolds with headers and true dual exhaust.
These things will improve the performance of the stock configured engine dramatically.
Do a search here for info. More posts on this kind of thing than you can read.
I would get rid of any computer controlled stuff for the engine (may require replacing the carb with an earlier year 77-79 are among the best q-jets IMO) and any emissions control equipment as well if your state/area does not require emissions testing.
Then look for Lars' papers on performance tuning your car. Replace the stock exhaust manifolds with headers and true dual exhaust.
These things will improve the performance of the stock configured engine dramatically.
Do a search here for info. More posts on this kind of thing than you can read.
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
search for LARS tuning guides here and that will give you the most out of what you have.
Like mentioned, money and time.
heads and cam is a good base.
There are a lot of threads on this subject where the L48 engine was the base to start with.
L81, what you have is a cross between the L82 and L48 engines.
Anything done to these motors will improve your motor.
Like mentioned, money and time.
heads and cam is a good base.
There are a lot of threads on this subject where the L48 engine was the base to start with.
L81, what you have is a cross between the L82 and L48 engines.
Anything done to these motors will improve your motor.
