Need more power!!!

[delta949]

Hi.

I have a Corvette from 1975.This is a L-48. The engine is 100% original and has only 165 hp.
Could any one give me some advice on how to get some power from this engine. What is the diffrence between the L-48 engine and the L-88 engine?
I have been looking at the tuning parts on Summit, but there are so many parts to choose from ;help

 

[Vette79]

Do you want to break from originality?

 

[KANE]

Hi.

I have a Corvette from 1975.This is a L-48. The engine is 100% original and has only 165 hp.
Could any one give me some advice on how to get some power from this engine. What is the diffrence between the L-48 engine and the L-88 engine?
I have been looking at the tuning parts on Summit, but there are so many parts to choose from ;help

More power- heads, intake cam, carb
Lots of choices. For the money, you'd do well with a top end kit and then have them installed by a shop in your area. The cost of a GMPP crate with shipping would be very high.

L-48 and L-88- The L48 is a small block and the L-88 is a big block.
L-88 Stats- http://www.corvetteactioncenter.com/specs/l88/l88engine.html
L-48 Stats-
http://www.corvetteactioncenter.com/specs/c3/1975/75specs.html
http://www.corvetteactioncenter.com/specs/c3/1975/75id.html
Hope that helps!

 

[Vette79]

That's what I did. Top-End Build with Heads, Cam, Intake, Roller Rockers, Headers, Carb, etc. Still trying to dial her in though. Good place to start if you want to work off the original block. Keep all of your old parts in case you sell later or want to go back to original.

 

[Rodney Gold]

I did my weak 81 over , Edelbrock ally heads , 290H cam , 10:1 compression , aftermarket intake , holley 770 street avenger , MSD, ceramic coated headers , new SS exhaust system etc etc , got great power.
BUT the biggest difference after doing all that was to swap out the Torque convertor to a 2200 rpm unit and change the rear end from 3:1 to 3.55: 1
Best bang for the buck in most cases is intitally a set of decent headers , then the cam and heads etc.

However the lesson I have learned form many build ups is that the car as a whole has to be looked at and that incremental upgrades are generally not satisfying or cost effective. IE if you gonna do the hop up , bite the bullet and go the whole hog rather than a new carb and then a new intake and then a new whatever.
There is of course another option and that is to remove the original motor and store it and drop in an aftermarket crate type motor .....you have to work out what would suit your pocket better and if yours is a desireable nos matching type model or is potentially one some time in the future , this is the way I would go

 

[delta949]

Hi.

I have been looking at some cylinder head combos at summit racing.

I have found two set that I think will do the work for my engine.

http://store.summitracing.com/partdetail.asp?part=SUM-CEDL402&autoview=sku

http://store.summitracing.com/partdetail.asp?part=HLY-300-503-1&autoview=sku

 

[grumpyvette]

of the two, the second kit looks better if youve got a manual trans, youll need a 3000rpm stall converter to run an auto trans correctly

http://store.summitracing.com/partdetail.asp?part=HLY%2D300%2D503%2D1&autoview=sku

 

[delta949]

I run with a new ovehauled TH 400 automatic trans.
The tourqe converter is a:
http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM-G2700-1&N=700+0&autoview=sku.

Do I have to replace the orginale Rochester Carburetor?

 

[GerryLP]

Again, this is common question posted here, and you can find lots of recommendations on what to do. Just remember, that the way the L48 is right now is due to the "balance" in components matched. Think what you want to do, and aim for a matched combo. There is no magic one-component change that will yield gobs of horsepower.