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I going to be taking the head off next week and I might as well get a thicker head gasket for my R33..

My current mods are Power FC, HKS2530kai turbo, Z32 AFM, FMIC, Custom TuneAgent Exhaust manifold and split dump pipe 3", Bosche 023 fuel pump, Im running around 18psi boost, and I wanna be on the safe side and get a thicker head gasket.

What size/type is recommended to suit an RB25DET?

Also, are there any gasket kits available for an RB25DET, including intake plenum gasket etc??

Cheers.

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hi mate,

a 86mm would probably be best, by 1.5mm

Im going to use a 87mm x 1.2mm head gasket

you can buy genuine complete nissan gasket kits for around $200

for example, lewis engines sell head gaskets and gasket kits http://www.lewisengines.com.au/category2_3.htm

although better prices can be found on the net

example : http://shop.rawbrokerage.com/category.sc?categoryId=20

edit: I ended up buying a heap of gear for the head from Erics Performance Parts, usa ebay, when the usa $ was 1.03$ to the aussie dollar so made it quite a cheap buy-up exercise

mind you, my complete rb25det head job will set me back around $4500

I wouldnt go bigger with that setup. All you will do is lose a little response.

But if you want to upgrade the gasket to a metal one you cant go past Cometic for Price and quality.

I would recommend the 1.2 or 1.3mm.

As for gasket kits i just bought one from Andrew at Kudos Motorsport here on the forum, cheapest ive found.

yep Cometic is the brand name Ive chosen for the gasket set(s)

good pricing and excellent quality in the flesh.

must admit I stole that website link from ntsky, =) always have a look there, nice site

you can read about my head work here:

http://www.skylinesaustralia.com/forums/He...&hl=tangles

Thanks for the prompt reply guys, Tangles thats a nice list of items you have there for your head work. :P

I think I'll end up going with the 1.2mm by 86mm.

Another thing that I was told was that I might need to get new head bolts as the old ones might be stretched at wont tension properly once put back in place? Is this true? Or do I just re-use the standard/old ones?

Simple answer, no.

Taking the head off and taking the engine out are two different ball games. Also its a waste of money for the power your going to be pushing, stock internals will be fine.

So i would have to get the engine out, the RB25 oil sump isnt bolted on the bottom?

out of curiosity why is the head coming off?

what power is it pushing?

Long story short, there is a hole behind one of the exhaust manifold studs and its leaking oil.. the reason the hole is there is because a mechanic drilled through there to get a broken stud out and ended up drilling through the block into the oil gallery, so im taking it off to get it welded as i have tried to use sealers and everything else and nothing has worked so far..

so i thought i might as well change the head gasket along with the rest of the intake gaskets etc. while the head is off..

power at the moment is 230rwkw @ 20psi with HKS2530kai, this is why im getting a thicker metal head gasket as well..

Edited by EVL-R33
So i would have to get the engine out, the RB25 oil sump isnt bolted on the bottom?

You want to build a motor with the block still in the car....

Also no need to go a thicker metal head gasket, your choice though. When i take my head off in a few weeks im just replacing mine with the standard nissan one in the engine gasket kit. No reason to lower compression at these power levels.

incredible, i know a guy that had the same thing happen, re the exhaust studs/drilling into head.

however he made the mechanic pay for the f**kup, took it to another mechanic and got the first one to pick up the tab for head removal and all other associated repairs/parts.

mistakes happen, but the story i got told was it was a bit of a mess once he was done.

You want to build a motor with the block still in the car....

Also no need to go a thicker metal head gasket, your choice though. When i take my head off in a few weeks im just replacing mine with the standard nissan one in the engine gasket kit. No reason to lower compression at these power levels.

The place I will be putting in the pistons has a hoist so if the sump comes off, it will save some time and i wont have to get the engine out... but if the RB25 sumps dont come off then obviously i will have to take the engine out..

I was told differently, to actually lower the compression a little so i would be able to run more boost (20-25psi) because these turbos can produce it and my current application can handle it. The gasket which i ordered is a 1.2mm by 87mm, so its not too thick...

incredible, i know a guy that had the same thing happen, re the exhaust studs/drilling into head.

however he made the mechanic pay for the f**kup, took it to another mechanic and got the first one to pick up the tab for head removal and all other associated repairs/parts.

mistakes happen, but the story i got told was it was a bit of a mess once he was done.

wow, so im not the only one that it has happened to... the mechanic has paid for his mistakes which was good.

do you know how he ended up fixing his? or did he actually get it welded like what im going to do?

PS> Sorry for double posting, but i dont know how to delete posts on here..

Edited by EVL-R33
Not sure if a 2530 will be much efficient mast 20psi.....

not really big power figures im after at the moment, just wanna have peace of mind, running over 20psi with a stock head gasket is a bit scary at times... i will be in the market for a bigger turbo in the next couple of months anyways...

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