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Best Head Gasket for 250Kw RB20DET??


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Any advice on a head gasket to suit an RB20DET with extensive headwork,

T4/T3 Backcut, R33FMIC, 3"complete Exh, 550ccRX7 Inj, TurboClub Intake Mfd, Int/Exh Cam gears, Custom Auto, 2800 RPM Soderstrom conv, AWD.

I want 250Kw at 4 wheels out of 2.0 ltrs so I guess I am pushing it :bs!:

Do I go Standard Factory which I have already bought but having 2nd thoughts,

or Copper custom and hylomar or..

Stainless shim style.

If Copper or Stainless, what thickness??

( Considering I have hogged out a bit from each combustion chamber already)

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Good luck TurboX. I use the standard gasket on the Rb25 for 220rwkw but I also have the block O ringed so don't anticipate any problems if I push for over 300rwkw (one day).

I have used a butchered RB30 head gasket on the RB25 with 11psi of boost and found that it pushed out into the water jacket after 10 000 km with resultant overheating. The metal reinforcing is not as wide on the RB30 as the RB 25 but I would stil strongly recommend the insurance of O rings. They cost me $165 and I provided the OEM gasket for location and thickness calculations.

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I am still using the stock one on my GTS4 thats making around 217kw @ 4wheels on a conservative dyno.

Where abouts are you going to dyno your car? I have dynoed mine on the XTC/complete auto 4wd dyno in coburg.

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Any advice on a head gasket

Thanks for the advice everyone, I guess the common idea of sticking with the standard one is at least going to save me paying out more for something else.

The main worry I had was that the reason I asked was the original one was coroded on the rear of the back cylinder as was blown through to the water jacket. This was found out after I had removed the intake manifold to repair the hose under there after blowing it half way down the 1320 at Calder one friday night. Had to flat tray it home and explain to the wife why her car was no longer drivable. :Oops:

Anyway when I had replaced the hose and refitted the intake manifold etc and started it, the oil pressure dropped imeadiatley and we shut it down.

After removing the head the problem with the head gasket was obvious as about 25mm of the cylinder edge was missing.

I am not going to speculate why this may have been the case but it was not long after dynoing and upping the output to 180Kw @ 12PSI.

Although there was evidence of corrosion in the block behind the metal rim of the gasket which means it must have been leaking for a while. Luckily none on the lip where the rim needs to seal on the new gasket.

Of course if you take the head off you HAVE to get it ported polished etc etc.. new Adj Cam gears etc. Anyone ever seen a $40K R32 GTS4?? :P

Guess I have had it for 7 years....

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I am still using the stock one on my GTS4 thats making around 217kw @ 4wheels on a conservative dyno.  

Where abouts are you going to dyno your car? I have dynoed mine on the XTC/complete auto 4wd dyno in coburg.

I have been talking to a few places but maybe Domenic at PRO -TEK in Hiedleberg, they have an AWD dyno and he seems to be up on Motec which I may piggy back to Chipped ECU as an Auto GTS4.

What have you done to your GTS4? Is it manual?

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What have you done to your GTS4? Is it manual?

Of course its manual!

Some of the mods i have are:

Full 3' exhaust

Hi flowed R34 GTT turbo

NISMO 550cc injectors

HKS cooler

Chipped ecu

Z32 airflow meter

I used to run a mircotech but that had sh1t economy among other things.

Haven't taken it down the 1/4 yet but will do 1 day.

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Of course if you take the head off you HAVE to get it ported polished etc etc.. new Adj Cam gears etc. Anyone ever seen a $40K R32 GTS4?? :)  

Guess I have had it for 7 years....

LOL, no but i have seen a $40k GTST :) and try 4 years :)

When your head was off, did you tidy it up yourself, or did a Vic workshop do it for you?

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Of course its manual!  

Haven't taken it down the 1/4 yet but will do 1 day.

Well Excuse me! ;)

Just that the manuals seem to be a bit rarer and I originaly wanted one, but now I have the auto beefed up I am happy to run it, even around Phillip Island (2.04)etc.

What power are you getting with those mods which are similar to my car?

I could only manage a 14.1@98mph -2.6 60ft last time at the drags when I blew the Head gasket after getting about 170RwK on the dyno.

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LOL, no but i have seen a $40k GTST :) and try 4 years ;)  

When your head was off, did you tidy it up yourself, or did a Vic workshop do it for you?

I did get The Head Stud to do some work on it, porting, 3 angle cut, guides, but they did not do anything in the chambers and left very sharp machined rings around the valve edges with the valves recessed nearly flush. :)

I figured that the flow on opening at low lifts was going to be extremely poor so got stuck into all the chambers relieving around all the valves and smothing out all machining. Of course I got carried away and have fully relieved everywhere and removed all sharp edges and polished everything myself. :)

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On another topic, since you are using rx7 injectors, is it true that the rx7 injectors since they are for a rotary have a different spray pattern than a normal injector?

Not sure about that but I would not be surprised if they are different spray.

I do know I had to modify the connection by cutting away the little internal plastic keyway so the standard RB plugs would go on OK.

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A stock gasket is fine. twice that power can be made with a stock gasket if the tune is right. R32 GTS4, 100% stock internals, 10.21 @ 134mph, pump gas, road car.

As I intend to tune it right -probably with a Motec M4 piggyback (its an auto) I guess the stock gasket will do the job by the look of your GTS4!!

I dont aspire to 10's but maybe it is possible if you want to point me at more on your 10 sec GTS4. Others are getting 10's from 2 Ltrs but I have not seen an RB20 powered skyline getting anywhere near that before.

Most try and tell me its gutless and fit an RB25/26/30.

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Well Excuse me! ;)  

Just that the manuals seem to be a bit rarer and I originaly wanted one, but now I have the auto beefed up I am happy to run it, even around Phillip Island (2.04)etc.

What power are you getting with those mods which are similar to my car?

I could only manage a 14.1@98mph -2.6 60ft last time at the drags when I blew the Head gasket after getting about 170RwK on the dyno.

Have you got any suspension work done when you go to phillip island? How does the GTS4 handle on the track? It's another one of those things that im still planning on doing. :)

am i right to say that when you got that 14.1 it was done with the stock turbo?

My turner (Dr Drift @ XTC) rekons a mid to high 12 is possible with a good launch seeing as that 210kw was done on a conservative dyno.

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Have you got any suspension work done when you go to phillip island? How does the GTS4 handle on the track? It's another one of those things that im still planning on doing. ;)

am i right to say that when you got that 14.1 it was done with the stock turbo?

My turner (Dr Drift @ XTC) rekons a mid to high 12 is possible with a good launch seeing as that 210kw was done on a conservative dyno.

I have fitted JIC HD Coilovers with pillowballs (bought as new Reco $1400) Fitted, adjusted and aligned by Ralph at TRU Track in Nth Melb. Handles well and is stable at speed but frontend ploughs a bit on tight corners. May look at GTR rear bar to solve this. A bit of weight upfront with extra large Oil and Trans coolers and fans as well as R33 FMIC.

Turbo is T4/T3 Backcut ATP special. Getting new S/S 3" Dump and separated Wastegate pipe joining back in about 30" downstream.

If I could get it off the line and a decent 60' it would be low 13's maybe :)

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I have fitted JIC HD Coilovers with pillowballs (bought as new Reco $1400) Fitted, adjusted and aligned by Ralph at TRU Track in Nth Melb. Handles well and is stable at speed but frontend ploughs a bit on tight corners. May look at GTR rear bar to solve this. A bit of weight upfront with extra large Oil and Trans coolers and fans as well as R33 FMIC.

Yeah, i get massive low speed understeer aswell. Once i almost understeered right off a little roundabout into another car! (i wasn't trying to go fast either)

My suspension work is limited to a set of kingsprings and koni shocks, which came with the car when i bought it 1.5 years ago.

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