Camshaft combo?

[wranglerunner22]

Hey all I have kinda an odd combo that I thought I would ask about before I commited to it.

Anyone see any issues with doing a HKS 264/BC272 combo?

Thoughts/comments appreciated thanks guys

 

[turboglenn]

I don't really see any issues with it, of course i don't know the real difference between the HKS and DKS 264 intake cam either. I run the DKS 264/272 combo and i like it, but i wish i had jsut gone straight 272's on both sides. I haven't had enough of a difference in the bottom end compared to any 272/272 cars that i've worked on to feel the little intake cam is benefiting in any way.

In the cam test in the dyno section some one went from 264/272 to 272/272 and gained power everywhere and said there was no notable decrease in spool

May i ask why you're doing this particular combo? Did you get a mis matched set some how for a good deal or what?

 

[wranglerunner22]

Well I was leaning toward that because I had a set of 264 hks's in the garage. And I picked up a good set of bc272's for a pretty good deal a few days ago.

But the combo fell flat on its feet... I took the 264's in to get checked out and whatnot, come to find out a couple of the journals are way way out of spec on the outsides.

Do you think 272/272 would be too much cam for running a Evo 3 16g? I have read mixed thoughts and am kind of unsure.

 

[Boostinsideways]

I am running the Delta 272s on a street motor with a 16g @ wastegate pressure. I didn't loose any spool, but there was very little mid range gain, most of it was at the top end.

 

[turboglenn]

I think, you'd love the 272/272 combo, I've been in a 16g car (2g GSX) that had a regular 16g and was running the 272s on both sides and it felt great. The spool was a little slow to start up for a 16g but the power was broad and the top end kept up a lot longer than a 16 normally does in setups i've played with (but then again i've never gotten 400+ WHP from one either - this car i'm talking about got to 372 IIRC SO CLOSE!! )

ONe thing that pops to mind that you might want to try is running a 272 intake cam and a 264 exhaust (providing you have good cams to put that combo together) i'm not an expert and i can't really say what the benefit is to it but i remember it being the "little secret", but to be honest that was so long ago i can't recal it if was for big or small turbos to get the most benefit

One thing you're going to really notice the benefit from is dialing in the cams to make the best use of them. Here's my personal favorite setup for 264/272 setup I have and it's faired very well on my friend's 272/272 car with a bastard 20g. advance the exhaust cam roughly 4* from centerline, then retard the intake cam about 2.5 - 4* also. what this does is decrease overlap, (increases idle quality and vacum at idle too) by deceasing overlap you cut off backpressure from the exh. manifold in the cylinder while it's being filled on the intake stroke. Many people doubted the effects years back when i brought it up on here but now it's even been proven by some one else in the cam-dyno shoot-out thread (forget the real name)

This is especially helpfull on smaller turbos, but makes a kick-in-the-ass difference on any setup IMO. With the smaller turbo that can't push as much air at any given PR compared to larger units, you're taking away one of the forces it has to fight when pushing air into the cylinders. I've tried EVERY other cam degree recomendation that's outlined in our basic guide in the tech archives and to be honest this is opposite of anything listed (it's not listed period) but it's given me the most notable improvement. Although in theory it takes away bottom end to increase the top end, you have the benefit of a small fast spooling turbo where there's barely going to be any felt loss in low end power (on my car with NO psi till past 3500 RPM you can really tell, and it's a dog down there, but on the bastard car it wasn't near as bad and our setups are VERY similar aside form turbo choice and tat he has a SMIM on a small'ish turbo...we even have the same FMIC's)

well, hopefully you have gears and that wasn't wasted finger motion , but to me CAM gears are something that i won't build an engine without after seeing how much i can really adjsut my powerband after having a set of my own to play with for the last several years.

I see a lot of people shrug them off and in one recent thread i saw a guy tell the OP to just take them off and run the OEM gears, HAH! he's never really played with a set is what i hear from that. mY new turbo was a bit doggish until very high RPM but I had also just rebuilt the head at the time of install and the cams were not properly "zero'd" Just using the gears to set them properly to "0" was incredibly noticable, then the added juice from my adjustment and i had a ton of mid-range back in the 4500 - 5200 RM range (where my turbo is JUST starting to spool some decent boost numbers round 15-20psi) Not to mention everywhere past these areas gained a bit of power that you could feel with the butt-dyno


well, if nothing else hopefully you'll take a lesson from how i came up with this set of adjustments, and that's to GO OUTSIDE of what everyone says is the "best bet" and experiment, tune and make note of the results! YOU may find that what everyone else does is no where near what you really like and may find a setting that is kcik ass, but becayuse it's not "popular" no one runs it... it took me doing the adjustment that wasn't even made note of in the cam adjustment giude to find what gave me the best oerformance, might find yourself in the same boat in a week from now