I was planning to use Arp studs and a Cosworth gasket when I have the head put back on my car. One of the local tuners told me that the Evo 8/9 guys always use a Mitsu head gasket and that he would have recommended Cosworth head studs ($400) since the Arps are weaker than stock on some motors.

Anyone have an opinion on the Cosworth head gaskets? I've never heard anyone mention using anything other than Arp studs on a X.

 

Anybody have an opinion? I know some of you have pulled the head for some reason.

 

if the tuning is precise, you will be fine with stock studs, if money isnt a issue, why not upgrade.

if this helps im runny 654hp and 450tq @ 27psi on my rsx with stock head bolts, stock head gasket, i have had no issues on the dyno, track, nor street....

 

the studs are ment to keep the head from lifting.. NOTHING to do with tuning. whoever told you arp's are weaker. is such an idiot.

 

+1 to the idiot part.

 

I'm trying to find the article/thread I read a few years back, but there was a comparison of Cometic, OEM, and Cosworth head gaskets and their sealing capabilities. Turns out the Cometic gasket's performance sucked, and the Cosworth was even better than OEM.

Anyway, FWIW, I'll be using the OEM head gasket on my full rebuild... it's more than adequate if it's similar to the Evo IX gasket.

As far as head studs are concerned, ARP 2000 is a very good material and is definitely stronger than OEM. I'm not familiar enough to comment on the specific design of the Evo X studs, but I'm going to be using some for my own build as they never failed me on anything else.

 

Not at all. I'm sure there are some motors where the stock parts are superior. Evos aren't that common where I live so most shops have not opened a 4B11T before.

Thanks! It turns out the mechanic was just asking whether the Cosworth was worth the additional price over the OEM gasket. Since I have no reason to believe the stock one is better, I'm just going to go ahead and have him use the Cosworth.