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SilverArrow27
02-24-2006, 08:14 PM
Would it be possible to mix camshafts? For instance, mix an HKS camshaft int. with a JWT camshaft exh. as long as the degrees and lifts are the same or very similar?

rogoman
02-25-2006, 06:22 PM
I suppose you could but why would you want to do something like that. Even though the lift and duration may be the same, the acceleration ramps on the lobes, which determine rate of lift, may be different.

You may end up with some undesirable characteristics.

Cam grinders spend countless hours on dynos to come up with a matched set for the best performance according to the use intended.

Nikeboy355
02-25-2006, 08:38 PM
Well stated...

SilverArrow27
02-25-2006, 09:09 PM
The reason I asked is because I have a Tomei intake poncam camshaft laying around and since the poncam can only be purchased as a set, I was just curious if I could mix and match it up with a different brand. But I was doing a little research myself and I ended up with the same conclusion you did. I may just end up tossing the one I have and get myself another brand new set. Thanks for the info! http://forums.freshalloy.com/images/graemlins/patriot.gif

_Def_
02-27-2006, 05:47 PM
I think you guys are overstating how much "engineering" goes into the typical cam grind. I also fail to see how differing ramp rates would give negative affects. Putting a hotter cam in an otherwise stockish engine is a big game of compromises(just the nature of the beast), so it's not like you'd expect bad results.

If that intake cam is going for a good price I might toss it in just to check it out - PM me if you're looking to sell it.

TS4l
02-28-2006, 10:59 AM
I would put the one in you have and then buy and HKS 264 step 1 exhuast cam. Lots of people run smaller cams on the intake saide. Or you could get the HKS 256 and they would be pretty simalar cams. Having a larger than stock intake cam is simply going to draw in more air, so you'll see some benefit but with out the exhuast came it can't get rid of the exhuast gases as quickly as it draws in air so it will help to add the exhuast cam. It'd be like putting a bif turbo on and leaving the stock exhaust. It'll work but adding the exhaust cam will help it be more efficent.

SilverArrow27
02-28-2006, 09:47 PM
Def: Will pm you if I decide to part with it.

TS4L: After reading your post, it makes sense to give the HKS exhaust camshaft a shot first and if it doesn't perform up to my expectations then I can always sell the Tomei intake camshaft and replace with an HKS unit. Thanks...Still deciding if I want to go with stage one or stage two, most likely stage one.

My Tomei poncam camshaft is 256 degrees and 11.5 lift; would the HKS 264 degrees and 10.5 lift exhaust camshaft hinder any performance because of the lower lift?

TS4l
03-01-2006, 09:55 AM
There are actually a lot of people in Australia that do a larger intake cam and they make great power. Its all a matter of what you want your power curve to look like. What turbo do you have? If you have a smaller turbo it will be less noticeable but I think you'll end up being happy with it. In Australia I have also seen a lot of people that only change the intake cam and they usually have good low end power.

SilverArrow27
03-01-2006, 08:12 PM
Tomei 7652 is my turbo...same turbo as GTRS and GT2871R.

jetdriver
03-01-2006, 09:57 PM
I think the VTC on s14/15 sr acts somewhat like a bigger cam by advancing the timing, and it is only on the intake cam.