Heads For Lo5

LeRoy_93 · November 15, 2009

Hey all! So after 215K miles it was time to put a new engine in my 93 GMC Yukon. When I did the install I had them put Cam/Lifters/timing chain, valve springs, aluminum water pump, 160 degree stat, power pulleys, MSD distributor, Taylor wires, intake manifold, throttle body spacer, headers, and a Jet Chip. I've also got a K&N filter and full exhaust with flowmasters.....but would like to do some head work to the new engine. I've thought about going the Edelbrock route to match my cam and intake manifold.....but the price seems steep to me. Where are some good budget places to look towards for heads that would give good bump in numbers?

Oh, and I've been rattling the idea around of doing a new TBI unit from Holly. It claims to have good power increase....but can't seem to find much on it except from them. I'm thinking that after those last two engine mods unless I was to tear into bottom end with new pistons/crank that it would be tapped out for the most part. Unless I went with forced induction, and that's not really a route that I want to look down. Any help would be much appreciated on where to look. Thanks for the help!

Nytemare · November 15, 2009

Edelbrock is a budget performance parts company.

You look at any other performance heads you will find that they can be almost twice the price of Edelbrock.

Get yourself an LT1 intake and bolt it on...everything on a vortec 350 is so close, with the addition of a TPI intake, that you can use an LT1 computer chip in your ECM

I have been getting Conflicting info on this....but I beleive you can replace the heads ones from an LT1 also. If this is true, they have 58cc combustion chambers compared to your 64cc, this would boost your comp ratio by about 0.7 points.

Some guys say that the coolant passages don't line up...that's the only problem. Easiest way to check is just take an old head gasket from your truck and check it against an LT1 head.

Just the addition of the Intake should boost your Low end significantly, having individual injectors as opposed to a TBI with only 2 and working basically like a Carb

LeRoy_93 · November 16, 2009

Well the intake manifold is already set to roll....I've got Edelbrock's aluminum TBI unit....not sure if I mentioned that before. That thing has been bullet-proof for me. That's why I am kind of left to just doing the heads without tearing into pistons and crank. And with the ECU already done it runs strong....I just want to dump the factory heads for the last little bit of juice.

And I hear what your saying with individual injectors....but I think if that was more the route I wanted to go I'd have just put an LT1 in the first place. Which is why I'm also looking to just do the Holly Pro-Jection conversion for the TBI Chevy's. Anybody had much luck running that kind of a conversion?

Nytemare · November 16, 2009

You are better off with your block, and converting it than running an LT1

All LT1's are 2 bolt mains...aside from the corvette ones...and you have to be really careful getting one...they put 4.3L LT1's into a lot of caprices and similar cars. The only way of telling the difference is the 4.3L stamp on the rear driver side of the block.

Either way...

For a nice upgraded head try These

or These Edelbrocks and you get a new set of valve covers with these ones too.

The Edelbrock ones have a smaller Combustion chamber and larger valves than what you have now... and for 1200 bucks you cant go wrong.

96chevy7.4L · November 17, 2009

The only other thing about the LT1 that came in the corvettes is one they were reverse rotation on the cooling. Reverse rotation being the coolant went to the heads first not the block. The water pump is different basically everything. Also the water pump on them is driven off the camshaft. My dad had one in his corvette. Nothing conventional about it.