just woundering if it would work and if so what the changes would be like power and gas milage?

 

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but, the answer to your question is no.

 

You could find some huge improvements by installing a pair of milled 906 or 062 heads, but you can't use LT1 heads.

 

while lt1 heads look the same, they are actually different, lt1 heads use reverse coolant flow system, basically, coolant on an lt1 goes to the heads first, while ours is the other way around, is this right guys or the other way ?

 

That's it. You "CAN" do it but the trouble involved is not worth it for most people. The exception being if you have a machine shop for free labor at your disposal, a welder and a free/nearly so set of LT1 heads. The other advantage is you get the LT1 intake too.

The last thing I will say is that you could actually put a set of 305 pistons/rods/1 piece crank from an LB9 or L03 into A 4.3L V8 block and it would indeed be a 305 that had LT1 heads on it. An LT1 style 305 would be an interesting combo in the mpg/hp perspective.

With all that being said the idea of making a 305 based L99 is an interesting yet bass ackwards idea. If one did it they would definitely have a 305 that could be considered one of the top evolved 305s that could be created using factory GM parts.

 

could be good , but like u said while go with all the trouble, u can pick a pair of l31 vortec heads, get a machine shop to mill them down to 305 combustion specs and u got the best factory flowing heads for the cheapest buck, an l03 with good heads like vortecs , i nice cam like the lt1 cam , a good intake and a good tune is not a bad combo if u just want a budget 305 that is not such a damn dog, its not gonna be a monster of an engine but it will be way better than factory , if not matching or beating stock lt1 cars. Id be happy if my l03 moved like a lt1, why more if i dont race the car anyways, for now my stock l03 provides me with all the fun of a v8 and nice fuel economy.

 

ok so if i wanted to do the 305 base lt1 what would i need cuz i can get a high mile lt1 for a relitively low price and im looking to make some good power out of the 305

 

or would the vortec head make more power . im looking to get in to time attack or auto cross when summer comes and im trying to get some good power out of the motor

 

how about a 350 lt1 with the l99 crank... ala 302.... those old 302 s in the 69 camaros were a nice piece of muscle and to think of it as a fuel injected updated version makes me get excited...

 

If u can afford an lt1 swap then go for it, remember theres gonna be a lot of stuff ull have to make up or buy for the adaptation, an lo3 with ported vortec heads a nice high lift cam that match the heads with full exhaust done and tuned ofcourse should put u even in lt1 territory or even faster than lt1s if not in ls1 or close , but thats a lot of money but i bet it would be cheaper than an lt1 swap. Its nice if u are able to beat most lt1s and run close to LS1s with an engine that many people will not even take seriously.

 

Vortec heads will make more power. They were based on the LT1 head design, and then improved on top of the LT1 design. Vortec heads use the same chamber design as the LT1 heads, just with a bit more chamber volume than the aluminum LT1 heads. The exhaust ports breathe about the same. The intake ports on the Vortecs breathe substantially better than the stock LT1 intake ports. And best of all - the Vortec heads will bolt on with NO mods required to the heads or block at all to work! They require a different intake manifold, but thats it.