These cams have been around for a number of years now and I was wondering if these can be dropped in using stock EVO valve train.

Yes I have researched and here is what I cam up with.

GSC doesn't make any recommendations about putting these in an EVO, but if you look at the S3 for a DSM it "strongly recommends" using beehives. Now as we know the DSM doesn't use beehives but the EVO does, so does that make it adequate?

I did find a thread where they said they just dropped them in stockish evo and someone posted you couldn't but specifics were not provided after that claim.

Second part to the question, if you don't use aftermarket springs and keep the revs low can you get away with it that way. IE 8500RPM rev limiter vs 10000RPM rev limiter?

I await your replies and thank you for you input in advance.

If by stock valvetrain you mean running those cams on stock valve springs and retainers then absolutely NOT when running 272 profile and higher you must use aftermarket springs and retainers

Yeah you definitely cannot use S3’s on the OEM valvetrain.....

Has anybody even attempted it?

Why would you even want to? Do it right the first time or end up paying more later for a new head valves exc. when the stock springs float.

+1 No way it’s a worth while attempt. It’s equivalent to running high boost without a knock sensor. If you want to blow something up or drive over parts, then by all means go for it!

Give it a shot and lets us know what happens, we'll want pics of the results of course. Also, make sure you rev it to 9500 or so to make sure you get the most out of the camshaft profile.

No

Ideally anything over 10.9mm Of lift you'll want to upgrade the valve springs. The most aggresive cam i'd ever run on a factory valve train is HKS 280's. Anything with more lift Eg Kelford TX272's or S2's you'll want to upgrade the valve trian.

Even on HKS 280's i wouldn't rev above 8000rpm in fear of valve flout which is very likely.

So Short answer No. Long answer Def no.

After running it of course

I personally ran over 40psi for years on HKS 280s on stock EVO valve train with a 9K rev limiter with out a hitch, so that isn't a theory or myth. Now I know the HKS 280s ramp rate is very mild compared to these so....

I am not aware of any 272 that needs valve train replacements that doesn't sound right. so that being said, let me rephrase my original question, has anybody ran this combination or are these all theories, maybe good ones but only theories right?

Here is the thread I read where it didn't say it had valve train components. https://www.evolutionm.net/forums/ev...3-wowsers.html

Pretty sure GSC has it published somewhere not to go above factory redline on the S2. The S3 would be pretty useless with a factory redline.

Futhermore, just because you don't drop a valve doesn't mean it's a good idea. When springs float you get crazy harmonics in the valvetrain and before a catastrophic failure occurs you'll pound the ever loving **** out of your valve seats.

And to put the nail in the coffin, you couldn't do it even if you wanted to (well you could, but the end result would involve tears) because the stock retainer will hit the valve seal with any cam that has a lift higher than ~11.3mm (S2 is at 11.2 and S3 is at 11.7).

So to sum it up, has anyone done it? No. Should anyone do it? No. Will someone do it? Hopefully not.

ftfy.

Lolol

Can any one give me a reason why aftermarket valve springs are needed to run this cam or any cam really in a stock style setup. Keep in mind I was wanting to run stockish boost/turbo around 20psi and not reving over 7500. I was under the impression big boost and high revs make the springs unstable from doing there job. I am really looking for some good info here.