i've got a 89 rs. 5.0 tbi. to my knowlege the motor has never been disassembled. it has 200k on it, getting tired and i'm prepping for rebuilding it. i've already got some lt1 aluminum heads (#10207643) and pretty much all the bolt ons with a small shot of NOS. my major concern is when i decide to upgrade the cam, if i put a high lift on it, will my idle raise considerably? being as its speed density, will it lope or just keep constantly raising the idle until it smooths out? i would like to build it a little mean, cuz this thing will probably get taken off the street. i'm pretty new at this electronic thing so any help would be greatly appreciated.

 

well lt1 heads won't work without extensive modification, lt1 motors cooling system is a good bit different it would require welding passages in the deck of the head and then once again flat milling it straight along with other odds and ends.

 

and if you want performance, why are you contemplating rebuilding a 305?

 

i know the lt1 is reverse flow cooling, but i've put some of my old head gaskets up to the heads and they looked like they lined up. but it's not that big of a deal. i just thought since i had them i'd make them work

 

i was thinking about the 305 since since i had it. but i was also contemplating going with the 350. which in that case, how much of the wiring harness do i have to swap? just the computer/chip or wat? i've also been thinkin bout just scrapping all the wiring, converting my 700 to vacuum shift, and throwing my 327 in it. which if i did that, would i still be able to utilize my in-tank fuel pump?