Valve Choices

[Rustang Racer]

I'm rebuilding a C3 head that is going onto a 250 with a Clifford 264H cam. The intake is going to be milled flat so I can direct mount a HolleyWeber5200 at first (because I already have it), and later a Holley 500. The exhaust is fully ported and polished, the bowls are blended and pocket ported, and I did all I could to port the intake (which isn't too much). I'm going to unshroud the valves as much as I can. What kind of valves do you guys recommend and could you give me the original application for the valve too? For the exhaust I've heard about using 144ci, 1.44" intake valves as exhaust valves. I've also heard of SI stainless 1.50" valves. For the intake I have the old 1.69" valves right now and could go with the later 1.76" valves or SI stainless 1.80" valves. I'm not sure what application those SI valves are listed under though. What do you guys think I should use? Are there more good valves other than the ones I listed?

 

[Anonymous]

use 1.44 exhausts for the intake and use the late 70's 1.75 for the exhausts. Proceed with the unshrouding and porting and you should be good. I believe if you go up to the 1.80, you will have a few problems and have more work to do.

 

[CZLN6]

Howdy RR:

You've just about covered the relative easy upgrades. Others are limited by the small stem diam on our engines of 5/16".

The 144 ci engine uses a 1.468" intake valve. We have used them as exhaust valves in moderate performance street engines for some time now. They are somewhat hard to find.

The SI Industry valves are made specifically for 200/250 engines. They are 1.75" intake and 1.50" exhaust. The heart ache is that they cost about $10 apiece.

Why did you chose the C3 head to modify?

Adios, David

 

[Anonymous]

czln6 you say that the 144 intake valves are hard to find why is that ? I called the parts store not to long ago and you can buy them brand new for pretty cheap

 

[CZLN6]

Howdy All:

Hey Mav, how about some more details? Where did you call? How much is "Pretty cheap". Share the good news!

Adios, David

 

[Rustang Racer]

Thanks for the help. I chose a D3 head because when it was nice and greasy the 3 looked like an 8 :x

 

[Anonymous]

dang dang dang dang dang dang dang dang dang dang dang dang I called the O`reilly parts store again to see how much they cost and they don`t have them all they have is the exhaust valves :x I gess thats what they thought I said last time and I was gonna go buy them today too

 

[AzCoupe]

I stock 175 intakes and 150 exhaust valves from SI Industries. FSPP price is $7.25 each. I will be stocking valves from Manley as well, but don't have a price on them yet.

I'm in the process of updating my website, which will have a new page on valves. Hope to upload it this weekend.

Cheers....