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For sale, 305 Vortec heads 1996-2002 design. These are the performance heads, not the old style heads. $300 plus shipping. Below are the pictures of them.
Come on guys, somebody with a low-mile 305 TBI needs these. They would make a great improvement over the throttle body heads with the addition of a carb manifold and a carb-tbi adapter. You can leave them un-touched or port the exhaust side. With exhaust porting and the factory peanut TBI camshaft, you can have 300 flywheel HP. Put a nice little cam in it such as the GM Production LT4 and with full exhaust upgrades you can have 315-330 FWHP @ 5,500. Someone needs to grab these 059s before I have to. This is what my last set looked like. I put 265 RWHP down through the factory cast-iron manifolds and factory exhaust in a 1991 Fullsize G20 Van using a 9.5:1 compression ratio and a factory 305 HO cam.
They are the L30 heads, later 059 castings (2000-2002ish express and marine 305s) from the looks of the pictures. The ports are identical to the L31 heads. The chambers are different though, because they are 6cc smaller. They are shapped much like the older TBI heads but are still classified as a high flow, high swirl head. They do not have a swirl ramp in the floor like the TBI heads, thus flow much better.
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Quote:
Originally Posted by gchu
Will these work on a 88 305 TPI - not TBI?
If you buy the Vortec style TPI base manifold.
Last edited by Fast355; 09-13-2007 at 02:49 PM.
Reason: Automerged Doublepost
However, these heads will produce slightly less power due to a less efficient combustion chamber, L31 heads have a heart shaped chamber. You would be surprised how mcuh chamber shape can do for flow.
However, these heads will produce slightly less power due to a less efficient combustion chamber, L31 heads have a heart shaped chamber. You would be surprised how mcuh chamber shape can do for flow.
You would be wrong sir. The 305 Vortec makes MORE HP/TQ per cubic inch than the 350 does. The 305 Vortec uses the same spark advance tables in its PCM. The 305 heads have the same efficient chamber design as the 350s do. They are just smaller and do not need the little widows peak on the back side away from the plug.
You would be wrong sir. The 305 Vortec makes MORE HP/TQ per cubic inch than the 350 does. The 305 Vortec uses the same spark advance tables in its PCM. The 305 heads have the same efficient chamber design as the 350s do. They are just smaller and do not need the little widows peak on the back side away from the plug.
I stand corrected
However, i do know the Heart shape chamber promotes a better burn? Maybe its a bigger quench pad? There was an article somewhere that went through the advantages of this design.
