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Well, given the fact that Decking the Head/Block isn't going to cost me to much, in terms of price if Nissan is selling the standard Gasket for around $150, and a Metal Head Gasket is only going to cost $300, I think I will be getting a Metal Head Gasket, so in regards to the Tomei one i posted up, under the assumption that a standard is off the tables, Is this a good option are their other Metal Head Gaskets out there for RB25DET's that people could recommend?

Did you read any of the posts regarding price? Direct from Nissan is about as expensive as you will get. Have a look around, you can easily find a genuine Nissan headgasket for $50-$60.

For example, quick google search revealed me this: http://www.lewisengi....au/prod180.htm

Edited by Hanaldo

I think what Hanaldo means is genuine nissan you will pay a shit load for, but you can get generic stuff for about $40 that is pretty much the same stuff (and in some cases what gets put into the genuine parts packaging)

you said your a novice with engine internals; below is a write up, wont make you an engine builder but will make more things make more sense

http://www.skylinesaustralia.com/forums/topic/378823-engine-internals-comp-ratios-general-info/

metal head gaskets require a 7ra surface finish on both block and head, the lightest scratch / grinding mark you can feel and it will leak (the composite material gaskets need the grinding marks for something to bite into for better sealing) more details in link above

inside diameter of the gasket has little to no actual relivance to what size your current cylinder bore is, rb25 / rb26 / rb30 are all 86mm bore standard, and RB blocks can be bored out to 86.5mm 87mm and some to 87.5mm

thicknesses will vary depending on what compression ratio you want / want to keep. how to work out your compression ratio formula in link above

I personally I dont see any point to using a metal head gasket if standard head bolts are being used. both gaskets have a sealing ring around the cylinder, both will seal the chamber/ cylinder exactly the same, with the same head bolt torque settings. But with head studs, metal head gaskets wont "muffin top" anywhere it can like the composite gaskets

or if you want to go through all the effort and expense there is the copper + o-ring style gaskets

have you found out why the head gasket blew in the first place? if not then you could refit the head and spend all that $ and it could blow again as soon as you fire up the motor

I think what Hanaldo means is genuine nissan you will pay a shit load for, but you can get generic stuff for about $40 that is pretty much the same stuff (and in some cases what gets put into the genuine parts packaging)

na hes saying nissan is one of the most expensive places to buy a nissan gasket. the lewis engines link is a genuine nissan head gasket and is less than 40% of the price nissan charge.

metal gasket is a complete waste for a stocker motor, buy that one from lewis engines and spend the rest on VB

  • 6 months later...

Sorry to bump this thread, but does anyone know where I can get a stock RB25DET Neo head gasket from now? I checked out Lewis Engines but they don't seem to be selling them anymore, and Googling is just bringing up Cometic or other MLS type gaskets.

While I'm asking, if I'm removing the head, would I be better of going for a gasket kit like this:

http://www.ebay.com.au/itm/R34-GTT-Skyline-RB25DET-Neo-Head-Gasket-Set-Gen-Nissan-/110803994200?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item19cc6ec658#ht_1047wt_1037

Or just getting a head gasket and reusing the others? I imagine the exhaust manifold gasket will need replacing as well though.

Sorry to bump this thread, but does anyone know where I can get a stock RB25DET Neo head gasket from now? I checked out Lewis Engines but they don't seem to be selling them anymore, and Googling is just bringing up Cometic or other MLS type gaskets.

While I'm asking, if I'm removing the head, would I be better of going for a gasket kit like this:

http://www.ebay.com.au/itm/R34-GTT-Skyline-RB25DET-Neo-Head-Gasket-Set-Gen-Nissan-/110803994200?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item19cc6ec658#ht_1047wt_1037

Or just getting a head gasket and reusing the others? I imagine the exhaust manifold gasket will need replacing as well though.

Hey Hanaldo - I have a brand new Nissan OEM Neo 86mm head gasket you can have for $20 if you need one.

I ran 18psi with metal head gasket and it let go. I had the head refaced and the mechanic assured me it was ok but it went within 2000km i redid head again and put standard in did work myself and its been good for about 5000 kays now

I believe the theory behind metalic head gaskets is that they support the fire rings better if the engines sees very high non standard cylinder pressures and or detonation . Usually with HGs the fire ring moves or splits and when it does you lose the seal between the block and around the chambers .

I can't see the point of overkill on a std engine especially when OE headgaskets out of Nissan are usually very good .

A .

Yes should try to find out what killed the original HG first .

Haha this is why I didn't want to bump this thread. I think the OP already has his answer guys, it's been stated in this thread a number of times already. I am just about to remove the head on my internally stock engine, so I want an OEM head gasket and remembered that this thread had a link.

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