I put my cosworth m2's in my IX last wknd and it definitely hurt performance with out tuning i went from pullin my friends evo from 1 - 1 1/2 to losing by almost half a car so tuning here i come!

 

You mean M2s?

 

Be sure to save for a good port job too, as the extra lift isn't doing anything until/unless you do, except of course making harder on the valvetrain.

As far as InBev, I prefer my Stella Artois to be Budweiser-free, thank you.

 

Is the port job absolutely necessary? I mean removing the head can get very expensive, not to mention the added cost of porting it. Is this only the case for aggressive cams such as the Cosworth M3's?

 

A good port job is necessary if you expect to realize the potential of the cams. The factory ports cannot respond to anything over ~10.5mm lift. Therefore, with a stock head, any cam set with over 10.5mm lift is only going to make it more demanding on the valve train, and cannot return additional airflow in exchange. Realize that cams are just one component of the head and valvetrain, and the entire assembly is only as good as the weakest link. Yes, head porting is expensive.

The JUN cams are designed to make big power from the stock head.

 

wtf were you doing driving hard with new cams AND without a tune?

 

What are your thoughts about the Cosworth M2's on the stock head? With upgraded valve springs and retainers of course. I'm not sure I want to get into head porting and what not, but who knows.

 

Same difference really. I am pretty sure the lift on the M2 is 11mm if not i know for sure its way above a 10.5mm

I feel you Ted. I am swapping to bigger cams, and doing my head along with it as well as a few other goodies. If your not doing your own install then its smarter to pay for the install once rather than doing the head later down the road

 

Yeah it is 11mm, looks like i'll have to be a bit more patient in deciding which route to take.

So is it safe to say that the many people who have tried the M2's or S2's with just upgrading their springs and retainers with no porting haven't seen the full potential of their cams due to a restrictive head?

 

+1 they are 11mm on exhaust and intake.. so clearly above 10.5mm

 

The specs on these cams appear to be best suited toward a moderately sized turbo and a ported head. It'll definitely work with a stock head and upgraded valvetrain.

 

Well yes, because the port cannot respond to the increased lift. The situation is like having speakers that can deliver clean low frequency response down to 20 Hz, but the amp has 60 Hz cutoff. In other words, you can use the combination without any problems, but you'll never realize the full potential of the speakers.

Keep in mind that the recent AMS cam test involved a ported head. The difference in results will not be as significant with a stock head.

 

506whp stock turbo...nice. This sealed my deal for the s2's. I know I won't come close to 500...but it will be a decent attempt.

 

Nevermind

 

Very well said, I'll prob just save my pennies, nickels, dimes, peso's, rupee's, etc etc