Who uses Cosworth Cams (like the M2's with 11mm lift) with the stock valvetrain?

Just a few questions here:

What is your rev limiter set at?

When do you typically shift when driving the car hard?

How many miles do you have on the car with these cams and stock valvetrain in?


The reason why I ask these questions is that I have had Cosworth m2's in my VIII for roughly 2k miles and have had zero problems shifting at 7500 (stock rev limit)...

But now I am going with a different turbo setup (3065) and would like to rev a little bit higher.. The valvetrain seems to hold up very well with the cams .. while shifting at 7500.. but I am just going to need to shift higher.. I am wanting to shift at like 8k.

This question is to ANY ONE that can help:

Would you keep the stock rev limit and continue shifting at 7500 with the bigger turbo setup?

Or.. Would you change out the Springs, Retainers, and such to shift higher (like 8k) for that extra power up top?

Finally, would you just keep the stock valvetrain and just shift at 7700-7900?

Please help me on this.. .

Thanks in advance!

 

My motto is do it right the first time. With a bigger turbo you want a rev a little higher up top and you really want to invest in some springs my friend, it'll be one of those things that'll keep you from worrying.

James

 

at the stock rev limit your fine. Since your moving to a 3065r and will be reving to 8k then of course it would make sense to do your valve springs and retainers and while your in there just to the headstuds as well.

 

I agree.. I already have them on order.. I was just "clarifying" that I am making the right decision....

I ordered Supertech Double Springs, retainers, valve seats, seals, and a new OEM head gasket.. I already have the ARP Head studs (:

Any one know how much a typical shop would charge to put the springs and retainers in?

 

Anyone else have any input? I mean if you get to rev to 8K with upraded valvesprings/retainers on the M2's, aren't the rod bolts at risk of stretching then?

 

Got the M2 and have 3K on them, I reved it to 8K with the stock valve springs and retainers, but it’s not necessary since I got the stock turbo, so I shift at 7500rpm and some time's I go a bit higher like 7800-7900.
Mellon got 280HKS cams with stock springs and retainers on his evo 8, and rev the engine to 8500rpm, thats with a HTA35R.

But since your going to get a bigger turbo I think upgrading the springs and retainers is a must.

 

true but I don't recommend to anyone to do what I've done with my own car. I don't mind experimenting on my own

I'll be doing the BF 272 cams + BR head as soon as they arrive, it'll get upgraded springs/retainers.

 

I have Kelford 272's, which are very similar to the M2's, on the stock valvetrain. As long as you keep it under 8k it is fine. I would have liked to do springs/retainers, but I could not justify doing them (and pulling head) and not doing a port job, intake manifold, drop in pistons/rods at the same time. Just wasnt feasible money wise at the time. I am now going back to a stock turbo and I have no buisness reving past 8k anyhow, so no hurries.

SQ

 

Nuked, did you take your 3065 to 8K?

 

i have my M2s for almost 10,000 miles on the stock valvetrain. At the track the Rev limiter is around 8000rpm, usually 7900rpm...

On the street on the stock turbo i was changing gears at around 7000-7200rpm if i would push the car...

On the big turbo i push it all the way to the rev limiter at 7800rpm on the street but i dont really do it since speed is was over the limit... prefer to push the car only at the track...

Probably around September i will build the block and since i will remove the head i will do double springs/retainers and maybe i will even upgrade on the M3s...

 

Awesome, thanks a bunch for your input Kouzman! I hope others have similar experiences they won't mind sharing.

 

A buddy of mine has a built 35r, revs to 8000rpm on stock valve train. The head is basically the only thing that is not built other than the cosworth M2 cams. Makes over 500whp on pump/alky on my dyno (dyno dynamics)

 

Yes I took it too 8k with the Kelfords. I set the rev limit at 8k, and I did hit it a few times on accident.

SQ

 

Thanks for the clarification Nuked, does anyone else have any more experiences?

 

i am on the stock valve train with the cosworth cams. i have quite a few 8k shifts in 3rd gear. its right where i cross the line in the 1/8th. i shift at 7800 in first gear too. no problems yet. had them for about 9k miles