oversized valves

[scrape]

is anyone running oversized valves on a cpi engine? just wondering if the stock cpi can send enough fuel to support larger valves. thinking about going 2.02in./1.60ex. in my heads when i take them to the machine shop. i am so ready to get my truck back on the road. :tup:

 

[Icarus-54]

Re: oversized valves

Just raise the fuel pressure and read your plugs.Did the same thing with my blazer,but also had 1.6 rockers,ran about 63# fp,made a big difference.
Jack

 

[scrape]

Re: oversized valves

thanks for the help. i have a set of 1.6 roller tips on the way from Hood Tuned Performance. isnt the fuel pressure regulator adjustable?

i want to get my heads to the machine shop b4 the end of the week, but i only have one off of the truck. the drivers side is giving me a little bit of hell and the hours i work are giving me really no time but the weekend to work on it. i hope to have it together by the end of march.

 

[dgoodhue]

Re: oversized valves

Are you having the heads ported? What do they flow?

 

[scrape]

Re: oversized valves

Are you having the heads ported? What do they flow?

having heads gasket matched with 3angle valve job. will get machine shop to flow test.

 

[dgoodhue]

Re: oversized valves

having heads gasket matched with 3angle valve job. will get machine shop to flow test.

Your wasting your money with larger valves. The bottle neck isn't the valves.

 

[Ty 1885]

Re: oversized valves

Your wasting your money with larger valves. The bottle neck isn't the valves.

What would you say is the bottle neck ?

 

[dgoodhue]

Re: oversized valves

What would you say is the bottle neck ?

The intake & exhuast ports themself. Factory L35's flow in the high 170 cfm range on the intake. Factory Vortec are in the 220's with the same sized valve 1.94 intake valve. You should have decent cfm gains by doing a 3 angle valve job, but those heads would need to be fully ported to take advantage of larger valves.

 

[scrape]

Re: oversized valves

The intake & exhuast ports themself. Factory L35's flow in the high 170 cfm range on the intake. Factory Vortec are in the 220's with the same sized valve 1.94 intake valve. You should have decent cfm gains by doing a 3 angle valve job, but those heads would need to be fully ported to take advantage of larger valves.

thanks for the info. im gonna keep stock valves. after talking with you and the machine shop i agree they wont do me much good. plus the extra $300 to install them could be used elsewhere.

 

[Ty 1885]

Re: oversized valves

The intake & exhuast ports themself. Factory L35's flow in the high 170 cfm range on the intake. Factory Vortec are in the 220's with the same sized valve 1.94 intake valve. You should have decent cfm gains by doing a 3 angle valve job, but those heads would need to be fully ported to take advantage of larger valves.

:tup: