evovin

iTrader: (64)

comp 280's compared to hks 280's? anybody?

evovin

iTrader: (64)

^ ???

Ted B

iTrader: (6)

Apples and Oranges:

Comp Cams 280+
Advertised Duration 264 deg Int / 265 deg Exh
Effective Duration 218 deg @ 1.27mm Int / 218 deg @1.27mm Exh
Lift 11.0mm Int / 10.4mm Exh
Lobe Centerlines 104 deg Int / 112 deg Exh
LSA 108 deg
Upgraded valve springs recommended

HKS 280
Advertised Duration 280 deg
Effective Duration 222 deg @ 1mm
Lift 10.8mm Int / 10.2mm Exh
Lobe Centerlines 110 deg Int / 110 deg Exh
LSA 110 deg
Stock valve springs OK


The Comp Cams set needs a bit of cam gear work to make best power.

Speed Corps

iTrader: (36)

This is alot of good info. I am curious to know if anyone knows anything about XS Engineerings cams for the EVO 8. They don't post any specs but claim they have more lift than the HKS's. Anyone have any experience with these?

Randy

iTrader: (14)

Hmm wasnt this thread a sticky?

evovin

iTrader: (64)

does anyone have a comp 280 with stock valve springs????

Liqquid

Yes, but don't tell Ted

According to Comp's tech line, stock valve springs are good for boost levels below 30psi.

No, I'm not kidding... that's what they told me.

I've got about 1300 miles on mine, top end power is still great with stock cam gears, but I might get one adjustable for the intake side to retard the timing a couple degrees.

Ted B

iTrader: (6)

That tech answer is worth a laugh.

As far as 'not telling me' about using those cams with stock springs, I'll refer to what your primary school teacher told you over and over again . . . "You're only cheating yourself".

In actuality, the problem with stock springs (aside from eventual fatigue) is the fact that the more aggressive the cams, the greater the loss in valvetrain accuracy as the rpms rise, due to deflection. The result is less power. Also, stock headflow data reveals the factory head is 'dead' above ~10mm or so of lift, so that's something else to consider FWIW.

FYI

evovin

iTrader: (64)

^ are u saying dont get the comps if im not changing my valve springs and retainers? so what do u suggest then?(drag racing) for 16g?

Ted B

iTrader: (6)

I can't really advise one way or another. All I can say is there is a reason why upgraded valve springs are recommended, and this is why.

Liqquid

He is correct, I do look forward to changing them out when I can, as well as having some head work done. And at that point might as well do head studs. and at that point, might as well do..... well, you get the idea.

However, if you wanna know more about people running them, call up turbotrix, they sell and install them, alot of them I believe.

mikesevo8

Thought I'd ask here ... do you know the specs for the Helix 272 V2 cams ??
The claim is that they are same as HKS, but are they really ???
I am trying to find out so I can properly set the cam gears.
I currently have them at -4I, -1E, which is a good setting for HKS, and my idle is smooth.

Ted B

iTrader: (6)

Unless they provide an accurate cam card, or, unless someone puts a degree wheel to them, it's impossible to know for certain.

erioshi

I'm glad to see this thread is still alive - both as a sticky and this version with new information. A huge thanks to Ted and everyone else who has kept it going while I was busy elsewhere.

It turns out that my Piper cams had the nitride coating fail and the surfaces facing the valve rollers pitted & chipped. That problem might be what caused the failure in my #1 rod bearing. Or all my track time just stretched the bolts - hard to say.

The end result is I need to pick out some new cams, lol.

Bonestock!

iTrader: (3)

I'd like to know this as well. Gruppe-S????

All I have found is:

Helix v2 272 cams
Duration / Lift
Intake 272 / 10.8
Exhaust 272 / 10.2