Im doing a budget tpi build stock bottom end port headss n intake and lt4 hotcam.i want to find stock heads that flow the best and make the best power. I plain on getting them at a junkyard. Anyone know a casting or part number to some good heads to look for? I heard chevy used some heads that made 285 hp on tbi systems but not sure if its true.

 

Ok so ive done some research. Found that the stock l98 iron heads with 1.94 valves are pretty nice after there ported and go with ****** valves. But I also just picked up a set of vortec 906 heads in a junkyard today. Not sure wat valve size they are or what valve size they can go to. Any suggestions on what woild make more power?

 

Vortecs. But, will require a new base. So, you're gonna' spend money one way or another; reworking the stock heads or going with the Vortecs. Also, keep in mind, stock Vortecs are only good to about .450 lift, so you may even spend some money on springs and what not. Power/speed require money.

 

Me personally would rather use the stock heads on TPI systems when on a budget build. Just have some porting/machining work and upgrade the cam & use 1.6 roller rockers & new bearings.

 

If both heads are ported and have the same size valves then wats the difference between them? Not sure of the cc size on either of them tho. But if there is a differee how much hp difference would there be using vortecs over stock heads?

 

Vortecs outflow the stockers by a good 30+cfm on the intake exhaust isnt much different. Better combustion chamber on the Vortec too.
Porting an L98 with stock valve size will only get you 220-230 if youre lucky. Exhausts pick up easily

 

Well if I did go with stock l98 heads id go with 2.02 valves but I head u cant go tgat big on stock l98s.. Its more like 201 or something close tho

 

I am going with rebuilt L98 heads. I think you'll be surprised with how well the stock heads can perform after being rebuilt.

 

Here's the flow numbers from my ported 113s with 2.00/1.56 valves

100 68 56
200 143 97
300 193 139
400 224 169
500 245 185
600 258 195

 

The 113s are stock l98 heads?

 

I had 2.02/1.60 valves installed in my 083 TPI (iron) heads.

 

113s were stock on 88-91 Vettes

 

If you go iron look into EQ cyl heads they have some decent stuff.
its an option

305 or 350?