SpiritOf76

So I'm CONSIDERING trying to spice up my original L-48 motor in my '76. Right now it is 100% stock, other than the headers and true dual exhaust. I'm thinking of starting with a cam kit and intake upgrade.
Of course, I'm looking a an Edelbrock Performer, but not sure which one.
I also have NO IDEA where to start when choosing a cam kit. As far as lift/duration, I'm clueless.
What has worked for you guys? I'm trying to get some more pep and get a nice deep throaty exhaust sound. Not TOO worried about speed, I won't be going to the track, but I would like a bit more power.

Crimson Thunder

Nice looking Corvette. With your wimpy 8.5 compression ratio,cam selection will be tough. If you go too much bigger on the duration you could bleed off more compression and make your car slower. Make a call to your favorite cam company and see what they recommend. It would be nice if you could throw a nice set of 64cc heads on at the same time. Good luck.

96 lt-4

If you aren't going to do heads then I(my opinion) wouldn't bother if more power is the goal.You would need to do valve springs for the cam.New springs and 1.6 roller/roller tip rockers would help your cam but then you are so close to a GOOD set of heads.Some 180 runner 64cc heads and a mild cam would be a good upgrade.

Intake depends on the carb you plan to run(q-jet or ???).At your power level an Edelbrock Performer will be fine for an aluminum upgrade.

Consider recurving your distributor to get your advance in sooner and more initial advance will help as well.

cv67

Assuming from the pic you have an auto and also assuming you dont want to change the probably tall gears or converter
Torque is cheaper to build than hp; youre headed in the right direction with reasonable expectations
What kind of budget are you looking at?

7t9l82

I agree you need to get that compression up.without that any improvement is peanuts.

dochorsepower

Assuming that you have not previously had any work done to it, you may be needing valve seals and valve job. In that case get rid of those wimpy L48 heads and get some good modern technology heads. Otherwise a cam change isn't going to do a lot of good. Modern design heads/combustion chambers provide better torque across the full range and even better cold start response.

SpiritOf76

For example? What do you recommend?

GUSTO14

I would give someone like JEGS a call and tell them what you are looking to do and your budget. Unless you want to spend some serious money and change pistons, I would ask about their Dart Iron Eagle, 180cc intake runner heads with the 64cc combustion chamber. These heads will give you a bump in compression and flow better than any heads GM put on the Gen I small block back in the day.
http://www.jegs.com/i/Dart/301/10111111/10002/-1

They will also wake up any cam you go with. Even the tried and true L82 cam will perform well with these heads.

Good luck... GUSTO

63mako

https://www.summitracing.com/parts/t...make/chevrolet

https://www.summitracing.com/parts/l...make/chevrolet

https://www.summitracing.com/parts/w...make/chevrolet

cv67

That will run pretty good for the buck spent

68post

Trick Flow makes some very nice heads and at a very reasonable cost also.

AboveTheLogic

Blue Print H8002K heads, ready to bolt on brand new for under $1k. I like mine so far. Plenty of power.

Crimson Thunder

I second the Iron Eagle heads that Gusto recommended. Use them with a Fel Pro 1094 head gasket.

MotorHead

You will not "feel" any change in HP unless you swap your heads out. There are a few iron heads ( to keep costs down ) that will get you near 250RWHp such as the Dart Iron Eagles and my preference the World Products Sportsman II heads that will support 500HP with the correct matching parts.

NewbVetteGuy

I'll just "10x" what everyone else is saying. Do not bother with the intake or cam, if you don't change the heads.

The article's getting a bit old but any of these heads would work: http://www.hotrod.com/articles/ccrp-...head-shootout/

Vortecs on the low end, Dart Iron Eagles, Jegs Heads, if you want the best heads for under $1200 a pair, IMHO, that's the Profiler 185cc / 64ccs if you want to focus on low end torque. -Don't forget the 0.015" FelPro gasket to keep the CR up as high as possible.

Then call a few of the big cam companies and tell them what heads you went with and they'll find you an appropriate cam for your heads and goals (torque vs. rpm focus). The L48s have very low stall torque converters (1650-1800) so unless you plan to get a higher stall torque converter, you probably should go with a smallish, torque-focused cam; although if you get some good flowing heads a larger cam could get some good perf gains and if you're willing to get a larger stall torque converter, that will make the car FEEL a lot faster (and actually be a lot faster).

-I think you'll be amazed at the difference some decent heads, a matched cam (which also means fixing the front-the-factory 2-4degrees retarded cam timing -probably more if your old original timing chain is stretched out); if you go with a higher stall torque converter to match the bigger cam -you'll have dramatically improved acceleration and the ability to do burnouts again. (A corvette that can't do burnouts is just a sad, sad thing, IMHO.)


If you haven't replaced your timing chain, you'll want to do that too to avoid catastrophic engine destruction. Then if you come across a current generation used RPM Performer or even an aluminum L82 intake for cheap, you can add one too, but don't expect much from the intake.


Adam

cv67

Like makos suggestion. That profile makes great tq on 350 383s, smaller TF heads and a dual plane he will have plenty of fun with it all cost effective. Good 650 carb curved dist probably got an honest 13 sec car that has good manners

ayellow56

I've been following this thread for a while now and have noted an omission that should be addressed. In regards to a cylinder head change no one has stressed the fact that if the block is not near perfectly flat the use of a .015 steel head gasket will almost certainly fail upon the initial startup and run in of cam etc. I've had numerous engines that have come to me in this failed state because that critical dimension was not checked when the heads were changed. So if a full rebuild is not in your budget use the Fel Pro composite head gaskets , giving up a little compression, instead of doing the job twice appeals to me. I just ad some initial timing to low CR engines ,seems to help some that have basically sound bottom ends. See Ya. Steve.

63mako

These Trickflow heads are 56 CC.

Sunracer

I would say find an inexpensive used L-82 aluminum manifold, keep your carb, stick with mild cam and associated bits, spend the money on some of the heads recommended here.

My thought is this will get you the best hp vs. $$ spent and skip purchasing a new carb and intake. The money spent gets you a long way to a good set of fresh cylinder heads with much better technology and a fresh valve seal.