unsure what to do with my Head

[boblong6]

I have a 7bolt head and I am unsure if I should get a 5 angle valve job and 1mm over size valves. Could someone tell me if there is an actual big gain from getting the head done and putting +1mm valves in it? how much hp do you gain from it. I heard you dont gain much and then I hear its a good idea to do it. I am going to be runng a gt35r with 272 hks cams, with bronze guides, bc springs and retainers and supertech valves. block is .020, redecked Brian crower rods, wesico pistons, multilayred gasket, ARP head/main studs.

 

[BogusSVO]

Here, read this

http://www.dsmtuners.com/forums/art...1g-head-flow-numbers-intake-designs-long.html


No one can promise you "big gains" with +1mm valves.
There are too many other things that play into that, intake, turbo even the air filter.

Will there be a gain in air flow... Maybe.. that will depend on the machine shop you use and how they install the valves.

If they are quick, and just cut the seats to fit the valves, doubt you will see much if any of a gain.
If they install them, and open the throat, thats where the gain will be.

Why a 5 angle valve job? why not a 6 angle ? or an 8 angle?
Do you understand what the angles are for and what they do? or how they are applied?

So you need to talk to the machine shop and find out just how they will install your OS valves.

This thread is not much diffrent than the one you started last week.
http://www.dsmtuners.com/forums/cyl...3049-questions-about-1-over-sized-valves.html

There are 3 machine shops that speak openly on a regular basis, and that is very odd to have that many on any one fourm. Then add to that a few others that are supporting vendors, and they post now and then.

Unless you wnat to pay some extra money to a machine shop to have your head flowed before and after the valve install. Your gains will be unkown. But a shop that has installed and flowed heads can give you a good educated guess of how much of an increase you can expect.