Help! Need help with engine upgrades for my 1975 L-48

[MTC_75vette]

I have just purchased a 1975 L-48 that has comp. roller rockers, heads were ported and decked, new Stainless steel valves, 3 angle comp valve job, new Edelbrock Perma Star polished billet Manifold, new Edelbrock 650 Thunderbird 4 barrel carb., Edelbrock tri-angular Elite air cleaner, new super comp. headers, new Flowmaster Delta 40 dual exhaust, torque converter, and rebuilt rear with 370 gears.


I want to get more power and I was told new cam, pistons, and heads will bring me a lot of new power to satisfy my needs. After doing research I saw there are a lot of different combinations I can order and I need an experts recomendation. I would like to keep price range to be reasonably affordable. My last question is if price is over $3000 am I better off tossing a crate motor in?

Thank You!

 

[KANE]

I have just purchased a 1975 L-48 that has comp. roller rockers, heads were ported and decked, new Stainless steel valves, 3 angle comp valve job, new Edelbrock Perma Star polished billet Manifold, new Edelbrock 650 Thunderbird 4 barrel carb., Edelbrock tri-angular Elite air cleaner, new super comp. headers, new Flowmaster Delta 40 dual exhaust, torque converter, and rebuilt rear with 370 gears...

Sounds like a good start with the parts above! Perhaps you just need a bigger carb (matched to your cam and heads) and a good tune up.

What do you want in terms of power? 300hp? 400hp? If you want those numbers, you'll need a good set of heads, matched cam, and the right carb.

 

[MTC_75vette]

Yes 325-400 hp is where I would like to be, what heads, cam, and carb do you suggest?

 

[80RedL82]

After mulling over this question myself, I decided on stroking my L82. Target was 400/400 motor as to not have to totally upgrade my drive train with the exception of solid u joints. My rational was that i could build a 383 stroker for the same price of modifying my 350 and could build a much milder engine (read reliable) engine without sacrificing performance. To be honest the difference between building a 350 and and stroker are neglishable but the tourque and HP numbers are worlds apart. Anyways I missed my mark and built a 460HP/480TQ stroker that pulls through 6500 rpms with more left in the tank.

 

[MTC_75vette]

You car sounds like it has a lot o power but how much are those stroker kits?

After mulling over this question myself, I decided on stroking my L82. Target was 400/400 motor as to not have to totally upgrade my drive train with the exception of solid u joints. My rational was that i could build a 383 stroker for the same price of modifying my 350 and could build a much milder engine (read reliable) engine without sacrificing performance. To be honest the difference between building a 350 and and stroker are neglishable but the tourque and HP numbers are worlds apart. Anyways I missed my mark and built a 460HP/480TQ stroker that pulls through 6500 rpms with more left in the tank.

 

[80RedL82]

To be honest, my engine isn't anything special. There are guys on here making much more power. I just couldn't think of a reason NOT to stroke it when I was doing the rebuild. Gobs more torque and easy making HP. I have an 80 with at least two weak points in my drive train, the TH350 transmission and the aluminum Dana rear. When I was thinking about my engine it was about the same price to rebuild the 350 and stroke it to 383 ci. I went with all forged components simply because thats what I was replacing in the L82. I bought from CnC motorsports, they have every conceivable set up. If you are rebuilding and switching out the L48 dished pistons, might as well just add the stroker crank. I stayed with 5.7 in rods for piston choice. The rest of the build is in my sig. To answer your question though I think I paid 1200 for the forged reverse domed sealed power pistons, SIR rods and eagle crank, bearings and rings. All internally balanced. My engine sounds very mild at idle ...that is no lopy idle no shaking at the light, but plenty when I push on the go pedal. Hope this helps in your build.

 

[MTC_75vette]

Thank you I will let you know what i decide to do.

To be honest, my engine isn't anything special. There are guys on here making much more power. I just couldn't think of a reason NOT to stroke it when I was doing the rebuild. Gobs more torque and easy making HP. I have an 80 with at least two weak points in my drive train, the TH350 transmission and the aluminum Dana rear. When I was thinking about my engine it was about the same price to rebuild the 350 and stroke it to 383 ci. I went with all forged components simply because thats what I was replacing in the L82. I bought from CnC motorsports, they have every conceivable set up. If you are rebuilding and switching out the L48 dished pistons, might as well just add the stroker crank. I stayed with 5.7 in rods for piston choice. The rest of the build is in my sig. To answer your question though I think I paid 1200 for the forged reverse domed sealed power pistons, SIR rods and eagle crank, bearings and rings. All internally balanced. My engine sounds very mild at idle ...that is no lopy idle no shaking at the light, but plenty when I push on the go pedal. Hope this helps in your build.

 

[Vette79]

Here's what I did this past spring. Hope this helps you...http://www.corvetteactioncenter.com/forums/showthread.php?t=103334&highlight=79+top-end+rebuild

 

[captdave]

more hp

Here's what I did this past spring. Hope this helps you...News: 79 Top-End Rebuild

Summit racing ,racing head service have top end kits, with matched components to get to 350 24 horsepower and it's all matched up and ready to go . I just bought 1 for 1300 dollars for the same engine.

 

[6880 Mike]

Why not drive the car for the rest of the summer and learn what you have before thinking about changing it? You might like the car as is.

 

[Vettehead Mikey]

This thread has been dead since 2008............................