# Heads reworked?



## Pontiachris (Oct 30, 2009)

i have a set of 7h1 heads that i pulld off my old 350 when i swap in my 455 the 455 has 4x heads with 114cc chambers giving me like 8.2 to 1 and being that i want to run all motor on pump gas i want to use the 350 heads which have 89cc chambers giving me an ideal like 9 or 9.2 to 1 the exhaust valve is the bigger 1.77 but the intake valve is the smaller 1.96 is it possible to have a machine shop drill them out for the bigger 2.11 intake valves i have in the 4x's?


----------



## geeteeohguy (Feb 2, 2008)

You can have a machine shop hog out the seat recesses and install new bigger seats that will take the bigger valves. It's what I should have done when I put a pair of #15's (87cc) on my '67 400. You need a competent machinist, though.They work fine, though. With the 89cc chambers in a 455, particularly if it's overbored any, you'll be close to 10 to 1 on the compression....maybe 9.75 or so. You need to do the math. May be a tad high, but it should run really strong. On 91-92 octane, depending on climate conditions, you should be able to run 9.5 or a smidge higher.


----------



## Pontiachris (Oct 30, 2009)

thanks for the reply ive been trying to narrow down my choices and i found a few reputable shops i just hope they dont charge and arm and a leg for the work


----------



## geeteeohguy (Feb 2, 2008)

I paid about $1100 to get mine done in the last year or two, and that's at a cheaper labor rate here in the Central Valley. But I needed all new valves, seats, studs, guides, etc. etc. Be prepaired to spend $600--$1800.


----------



## Rukee (Feb 8, 2007)

Just had mine done last summer, they were around $900 with all new seats, guides, valves and springs.


----------



## Pontiachris (Oct 30, 2009)

do they usually clean up the heads and resurface them when they do any kind of head work at a machine shop?


----------



## 646904GTO (Feb 10, 2008)

Yes most do but listen to these guys! Replace the guides, valves, springs, etc. Don't go cheap on the heads, you will regret it every time you start the engine and see that puff of blue smoke out back.


----------

