sr20det headgasket/head studs

[Loomis112]

I have been searching around here about which headgasket is best and which torque specs to use for the sr.

On this forum so far all I have see is bad stuff about the Cometic.

So first question would be what are your guys opinions on good head gaskets?

Another question is when replacing the HG do you have to resurface just the head or both head and block? Do you really have to pull the engine to do a HG job.

Also ive been hearing a lot about people running more torque than what arp calls for, then on the flip side I hear people complaining that anything higher than whats in the instructions would damage the block anything on that?

I guess last but not least what is the true hp rating of the stock HG and studs. Ive heard people sling all sorts of numbers around on different forums just curious if anyone truly knows...

Thanks

[Dboyizmlg]

300whp is about the limit for an average Sr20.
With stock HG/studs.

It all depends on the condition of the engine as all engines are not the same.

If it's a well condition compression engine, then I would say 340-350whp on stock HG/studs.
not your average Sr20, but there are people that have done it!
Just some food for thought

[Loomis112]

Good to know! In the future I wanna get tuned on Nismotronic and 300whp is pretty much my goal so far.

[e1_griego]

4+ years on stock hg/studs @ 350whp for me.

I just rebuilt the motor and put in the Mazworx ARP studs and a cosworth head gasket. If the tune is fine, 350whp shouldn't be an issue.

[cotbu]

Tomei
Apexi
Cosworth

You headgasket doesn't care how much horsepower or torque you make nor the amount of boost.
The number one cause of oem headgasket failure is detonation, another is craftsmanship. Sure there is excessive rtv and overheating related failures too, but only someone out of their mind, would say. Its because I made 351hp on a stock headgasket that's why it blew!
Anyone that puts a horsepower rating on an item like the oem headgasket, is probably trying to sell you something or is just clueless.
Remember NA engines blow headgaskets too!;)

The head and block should be checked for straightness, with an oem type gasket you can get away with a poor finish on the surface. That means if the block and head are flat, you can clean it and install an oem gasket. With a mls gasket the surface needs to be at least a 50ra for most gaskets. People will definitely tell you to deck the block and head.
What they mean is resuface, but you can do this by hand. So if all you are doing is replacing the oem headgasket? Take your time and clean the old gasket material off the block and head, straight edge the block and head. If you find the block or head high, low or warped? You should have them machined. At that point you can install a mls gasket if you choose.
The only time i recommend a decking is if you're doing a rebuild, if your engine is still in the car? Straight edge and a cleaning should be good.
Why put a straight head on a warped block?

Always use the manufacturers recommendation.

From a Highly Tuned Note 4.5!!!

[Loomis112]

Thank you cotbu that was very informative for future reference. I think ill stick to the stock head gasket for now and see what I can get done with the tuning again my current goal is around 300 or so to the wheels so maybe ill be good with the quality of the tune

[TheRealSy90]

Cosworth gasket is the best in my opinion, next in line would be the oem. ARP or Maxworx studs, the new design that bottoms out in the block correctly. OEM Torque specs, unless the stud manufacture specifies something different.

[jedi03]

I have seen 600 whp on a stock block...only internals were cams and an amazing tune...it ran for 5 years before blowing...was a verified 6000 mile engine from Japan and extremely abused after sold year 4 of it running.

[jr_ss]

Cosworth gasket is the best in my opinion, next in line would be the oem. ARP or Maxworx studs, the new design that bottoms out in the block correctly. OEM Torque specs, unless the stud manufacture specifies something different.

My only gripe with the Cosworth headgasket is the lack of a fire ring, otherwise it's a great headgasket. I think Apexi is probably the top tier gasket for SR's.

[TheRealSy90]

I've never seen a Cosworth gasket fail in and of itself, it's always been known to be one of the best available. Honestly no gasket should fail if it's properly torqued down, and the engine is tuned properly. Detonation and/or overheating is what kills the head gasket, rarely is it the gasket itself, or even the head studs/bolts.

[jr_ss]

I've never seen a Cosworth gasket fail in and of itself, it's always been known to be one of the best available. Honestly no gasket should fail if it's properly torqued down, and the engine is tuned properly. Detonation and/or overheating is what kills the head gasket, rarely is it the gasket itself, or even the head studs/bolts.

I agree, I never said Cosworth was a bad gasket. I've ran them in the past.

[Prok0]

I've always run APEX'i gaskets with good success. That and standard ARP 102-4701 studs.

Just make sure the block and head surfaces are true and clean and torque everything down properly and you should be good to go.

[Silverbullet]

You headgasket doesn't care how much horsepower or torque you make nor the amount of boost.
The number one cause of oem headgasket failure is detonation,



This is why many people go with OEM HG over a MLS one for under 400. If its detonating, there is osmething else wrong and it'll be an easier fix to replace a blown Nissan HG vs damaged piston components.

[Kingtal0n]

Right. Stock internals, stock HG, 350rwhp, 9* btdc max or less, and it should live forever.

[Tom N]

Can't beat Apexi and some H11 head studs. But neither are needed for a 300hp car.