TBI to CARB need advice on the heads
 

i have a 92 chevy truck with a 350 tbi engine but i want to convert it to a carb and my problem are the heads my cam is a hydraulic flat tapped and i bought the intake from edelbrock a holly carb and an extreme energy cam from comp cams mine is not a racing truck i just want it to sound nice, but the problem is that the guy that recommended te cam he gave me a 507/510 lift now i dont know if the heads will support the cam offcourse im changing the springs thats my problem i dont know if some one could help me out.

Re: TBI to CARB need advice on the heads
 

i dont think stock tbi heads will support that much lift, u need to trim down ur valve guides to make up for the extra lift , if u dont they will hit the guides when at full lift and ur engine will get fuked over, but why did u get a cam with so much lift if ur not going to race it or want more power out of it, theres plenty of cams with lift that stays under the heads specs and will give u that same loopy sound u are prolly wanting. More lift is not always good with stock smog heads, for one ur prolly gonna end up with shitty mpg, but since u wanna carb the motor u dont rly care about mpg anyways

Re: TBI to CARB need advice on the heads
 

thanks i got it cause the guy that sold it to me he works on a performance shop and i told him what i wanted and since my truck is manual trans he said that it was not going to be a problem.

Re: TBI to CARB need advice on the heads
 

stock heads only support about .480 in lift max. I agree to much cam for your needs. and those heads need major work to flow anything. you'd be better off swappin heads to like some sr torqers or somethin like that. Sounds like the guy at the shop just wanted to sell that cam bc he screwed up someone elses order and didn;t want to eat the cost involved.

Re: TBI to CARB need advice on the heads
 

Way too much lift for the stock heads. They're all done around .470" valve lift maximum. And a cam with that much lift indicates it's probably also going to want to operate in an RPM range a set of TBI heads aren't going to support anyway.

Think about a sub-5000 RPM operating range. Not that you can't rev it higher, but a cam that's designed to work in a 2000-5000 kind of RPM range to match the capabilities of the heads will get you better real world results.

A base model Edlebrock Performer cam kit would work fine (as would the identical Summit K1102 clone of that cam). Not very aggressive, but significantly hotter than the stock TBI cam and it would be a good match for the TBI heads.

Another alternative I've found works well with TBI heads is a mild single pattern cam (to complement the weak intake port but pretty good exhaust port of stock TBI heads). Something like the Comp High Energy 260 cam would be about as big as I'd go on stock heads.

Re: TBI to CARB need advice on the heads
 

Crane 272 H10 was a PERFECT cam for swirl port heads.