ok, for the truck 350 i am putting into my RS, i bought a set of higher compression heads (641 casting 305 heads, have been mildly ported, 58CC combustion chamber)

my teacher told us that for mechanic school, we can rebuild a set of our own heads this semester........only thing is, these heads have barely been used, so their in great shape

what i would like to know is, how hard would it be to change the valves to 1.94/ 1.50 valves? do i just disassemble the heads and re-assemble with the new valves OR do i have to modify the head where the valve seats?

thanx!

 

You must have the valve seats machined out from 1.84 to 1.94 inches. This requires a special grinding machine that head shops have. Once that is done and the proper angles machined into the new seats, you can have the new 1.94" valves ground to properly fit them.

It should already have 1.50" exhaust valves.

 

You sure about that casting #? I saw "601" and "416", but not "641".

Just asking, because if they're swirl-port heads, you don't want to bother with them. Bigger valves won't help anything. 416's would be okay, and I believe the 601's are what you ported, right, Bull?

 

sorry, they are indeed 416's

i wasnt thinking when i typed that

well, in class i dont think we are allowed to machine the heads, so i guess this idea is out

although, next semester i can take a machine shop class if i have the time, in that class we are allowed to do cool stuff like that

 

Yup, 601s are what I have. Although one of them says 801, no matter how hard I try to see 601