I have a set of L98 heads, casting number 083 and was wondering if these would be worth keeping for a 350 re-build? the block is from a 75 chevelle and i have all the tpi stuff.

just looking to build a decent street engine, i'll be able to do any porting myself when the time to build the engine comes. id probably stay N/A and keep things simple. id like to shoot for 350-400hp at the crank. could i do it with these heads with enough machining and a TPI set-up with siamesed runners, ported plenum and manifold?

I only ask now because i'll be junking my thirdgen and wondering if i should keep these heads, to use or sell, or just junk em with the car.

 

L98 heads should be 083. But L98 heads are very good for what you want to do. Follow the link at the end of my sig for a how-to.

 

ok, just double checked they are 083's. thanks for the quick reply

 

I don't think you can make 400hp with any form of TPI, even siamesed runner and ported crap. The runner length is just to long to make that kind of power.

 

I'm currently installing a fully ported set of 083 heads still using stock cam and Accel TPI. Have some 083 heads on now with mild bowl blend. See sig for times in 8th mile. Strong mid range power and good power down low. Not much on top end though. Will see if more head flow results in more go under current modification conditions. We'll see if cam is holding me back or if heads are still the weak point. The stock cam is 206/213 & .415/.430 BTW using 1.5 ratio rockers. When I install these fully ported 083s I will use some 1.6 rockers. Hope to have running tomorrow, and some times next weekend...8th mile for now of course.

 

are those numbers off all stock L98 cams?

 

Yeah, you need more cam. That stocker only breathes up to around 4500 rpm. Even a cheap old LT1 cam ($50) will make a big difference for you.

 

I realize I can use more cam...but still hoping for improvements with the heads and 1.6 rr. I can still even get a new torque converter and some suspension mods, etc. and theoretically make improvements before diving into the short block. Looking to go low 8s/ high 12s with this cam actually. I have some other cams and short blocks ready when the time is right.




I believe the earlier L98 cams had some milder numbers.

 

You don't need those L98 heads, I'll take them off your hands for the cost of shipping. :P

seriously, i need some heads for my new project. It is called project cheap-***. I want to see how cheap i can put together a 350 motor. I've already got the block, and intake. I need cam, pistons, heads, crank. I think i'll splurge and actually buy new bearings and whatnot.