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Cams, the bigger the better?

Defiant

Well-known member
Joined
Sep 7, 2012
Messages
162
Location
Houston, TX
I have a question regarding cams.

We all know that bigger cams help rev higher and help up top, but hurt turbo spool.

My question is at what point are the cams over kill?

A lot of people run 272's but are there any benefits over something smaller, lets say 242's?
 

KiNgMaRtY

Well-known member
Joined
Apr 8, 2008
Messages
835
Location
Corona, CA
If you are on a stock sized turbo, 264's are good and will yield a gain but not a whole lot. Anything smaller and your not going to really gain anything for the cost, time and labor. Might as well stay with the OEM cams.
 

Defiant

Well-known member
Joined
Sep 7, 2012
Messages
162
Location
Houston, TX
I have an FP Red and I'm wanting to increase spool time. Currently have 272/280 cams but thinking of going smaller.
 

fuel

Well-known member
Joined
Feb 23, 2009
Messages
2,165
Location
Toronto, ON, Canada
the stock cams are about 252/256 duration, so 242 would be a big down-grade. As others have pointed out, 264 duration cams are just about right, and incidentally are what the Evo 8 are running stock.
 

GSTwithPSI

Well-known member
Joined
Jan 1, 2012
Messages
3,460
Location
SoCal
You can improve spool via tuning. You can also swap in smaller cams tailored to better spool, but I'd bet you'll probably see minimal gains, especially without being able to degree the cams. The FP Red is a middleweight journal bearing turbo in a bolt-on FP turbine housing. There's probably not a whole lot you can do to get great spool up out of that turbo. A similarly sized ball bearing turbo would net you much better spool up times, no doubt.

If you want any meaningful advice, you'd need to provide a log of a 3rd gear pull showing your current tune and resulting spool times. A comprehensive mod list of what's currently done to your car would be required as well. Absent that data, any advice given is simply food for thought. My gut feeling would be there's probably ground to be gained in spool up times by simply tweaking your tune.
 

slugsgomoo

Well-known member
Joined
Oct 16, 2003
Messages
3,770
Location
Tacoma, WA
what are you revving the car to? what's the intake manifold & head setup?

I doubt for most people that a 280 is a good choice. Personally, straight 272 or even 264/272 is probably a more fun street car, and overall if you're on a 2.0 revving under 9k, probably a better choice.

That said, which cam makes a big difference, between HKS/BC/GSC/JUN/etc. so...
 

Defiant

Well-known member
Joined
Sep 7, 2012
Messages
162
Location
Houston, TX
Stock intake manifold
Fully built head
Revving to 8k

These are regrinds to HKS specs.

I'm defiantly going to go with a smaller cam setup. I'm leaning more towards the 264/272 cam setup.
 
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