Valve Choice

[stann999]

I am considering buying new valves for my new 600hp build. I have comp cams serious street for 2400-7300 rpm, and kiggly springs and retainers. I would like to know what kind of valves I should buy and also the benefits of running oversized valves.

 

[BogusSVO]

oversize valves, when installed properly, will open the bowl up and improve airflow, also if the std seats are badly worn the OS valve will keep the valve in the properplace , amd tip height, and spring installed height should all fall with in spec.

for your build, look at the ferrea valves, the EngnBldr ones may not take the stress of 600,

 

[Oliver@Slowboy]

Ferrea makes really nice stuff, but I personally like the Manley valves. Great performance, lower price. Also I would advise against the 1mm over, you can get just as good flow with stock size.

Oliver
[email protected]

 

[TSIfreek]

I would recomend ditching those cams and look into kelfords 272s or GSC S2s for a high HP motor.

 

[stann999]

What is the benefit oversized on the exhaust side alone vs. 1mm over on both sides?

 

[BogusSVO]

I like the +1mm valve as a "repaire" valve, I use them rather than change the seats out.

all you get is an increase in flow, IF the valves are installed properly, the throat of the seat has to be cut out to get the gain, if just the seat is cut, you will have no diffrence in flow.

if the head is ported, the +1mm will help find more flow.

if you go +1mm on the exhaust, you may as well go +1mm on the intake also.

 

[stann999]

Ok that really helps me thanks. I will have to see about getting the head ported before I go for the valves.

 

[BogusSVO]

whats your budget goals with your car?

porting will cost from $300 and up depending who and where you get it done, and if you have flow bench work done....

 

[ist dwa]

ferrea valves FTW