Replacing One Cam?

[SuzukiRidr326]

ok so im in the market for some cams and theres a guy selling a Intake FP Cam2 and i was wondering if you can run with one stock cam and one aftermarket cam or do they both need to be the same size?

Any help will be much appreciated!
Thanks,
Jon Blemler

 

[kahl23]

That shouldn't be an issue. People have been running 264/272 combinations for years without adverse effects. As long as the cam does not require an upgraded valvetrain you should be ok.

 

[twicks69]

Well for the fact that you would be running a 272 intake cam and a stock 2G Exhaust cam, you will end up with some decent flow restrictions on the exhaust side.

You can try to run it and see what happens, but I would still recommend running a 272 (FP2) or 280 (FP3) exhaust cam with it, along with upgraded valve springs.

Yes, you can run most aftermarket camshafts on the stock valvetrain, but the bigger you go, the more lift you have on the cam, and the likelyhood of valve float with stock springs and big cams.

You will also get a smoother powerband with upgraded springs as the valve events will be more precise and controlled.

I would suggest saving up the parts and installing them all at once (intake cam, exhaust cam, valve springs and retainers). You only need a single valve spring for your application on those cams.

 

[toofast82]

I think there would be a flow restriction as said with a 272 and a stock. Plus also when choosing cams with stock valvetrain, the cam's ramp profile will affect the necessity for upgraded valvetrain as well as lift,etc. The ramps dont become overly aggressive until you step up past 272s. You can effectively run 272s with stock valvetrain as long as you keep the revs under 7500rpm

 

[SuzukiRidr326]

kk thanks guys but i found out today that it is actually a FP2 exhaust cam, now ### kinda effects will running a stock intake cam and the FP2 exhaust cam have?

 

[twicks69]

In this circumstance, it would help, but you will still get greater benefits out of it when in conjunction with the intake cam.

 

[pboglio]

If somebody can get me some "accurate" cam specs on the stock 2g cam I'll run the stock intake/FP2 cam configuration thru my Desktop dyno.

 

[twicks69]

If somebody can get me some "accurate" cam specs on the stock 2g cam I'll run the stock intake/FP2 cam configuration thru my Desktop dyno.

I already have the data on this website. I will look for the thread and post up the link.

 

[SuzukiRidr326]

sweet..i found this

http://cranecams.com/pdf/Page174.pdf

 

[DougR]

Wow, Desktop Dyno! (Thread Jack!)

Have not heard that name mentioned in a long time! I use to own the Original single floppy version, But a virus ate it and have not since upgraded to the latest version.

How is it? From what I have seen its fairly detailed.

 

[pboglio]

Top h.p. curve is the FP2 cams , middle curve is the HKS 264/264 cams, the lower curve are the stock intake/FP2 exhaust cam. I used the available data from crower, fp, and used the HKS 264 intake valve opening crank angle value in place of the unknown stock value, otherwise stock duration and lift were used where applicable. H.P. values are relative and ball park, as the turbocharger selection has a big impact on the actual h.p. Pay attention to the relative values more than the absolute. YMMV.

Results as follows at 17 psi boost pressure:

FP2 cams: 348 h.p. @ 6000 rpms, 332 lb-ft @ 5000 rpms
HKS 264/264 cams: 332 h.p. @ 6000 rpms, 327 lb-ft @ 5000 rpms
Stock intake cam/FP2 exhaust cam: 308 h.p. @ 6000 rpms, 292 lb-ft @ 5000 rpms

Conclusion:

Bad idea