big lift on ported irons

[slimtastic]

im gonna be doing some port work to a set of stock 8445 heads and i wanna have them ready for a big lift cam as well(valve lift a bit over .500") i know that im gonna need springs and ill be changing the valves as well, but the tops of the valve guides for the exhaust valves will need to be cut down. how much of a cut on the top of the exhaust valve guide(and intake if needed) will yeild me enuff safety to run around a .510" lift? if ive left anything else out for running this setup then please dont be a stranger

 

[slimtastic]

can anybody help me out??

 

[NCTURBOS]

I don't have a specific answer for you, except... I can tell you that I run more lift than that on my Champion iron heads. You may want to call Tom @ Champion to see if they "need" to be cut down. You'll want to know what rocker ratio you'll be running also.


K.

 

[bruce]

Originally posted by slimtastic
im gonna be doing some port work to a set of stock 8445 heads and i wanna have them ready for a big lift cam as well(valve lift a bit over .500") i know that im gonna need springs and ill be changing the valves as well, but the tops of the valve guides for the exhaust valves will need to be cut down. how much of a cut on the top of the exhaust valve guide(and intake if needed) will yeild me enuff safety to run around a .510" lift? if ive left anything else out for running this setup then please dont be a stranger

Preassemble and measure things.
The pushrod length plays a big role in the actual valve lift.

 

[boostedLC2]

Re: Re: big lift on ported irons

Originally posted by bruce
Preassemble and measure things.
The pushrod length plays a big role in the actual valve lift.

Actually with hydraulic lifters the push rod length doesn't affect valve lift at all. The push rod length will set how much dry lash (distance from bottomed height) you have but as long as you're within the plunger travel there's no effect on lift.

HTH,

Jim