GTR Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
2,791 Posts
Discussion Starter #1
can anyone give some advice please on the limits of a standard headgasket. roughly....

I dont really know the measure so I am guessing in bar, hp and lbs ft...

really appreciate a quick answer or two please.
 

·
Registered
Joined
·
2,791 Posts
Discussion Starter #2
searched the Skylines downunder. Looks like standard HGs for cars under 600ps (wheels) are just fine.

Anyone suggest a limit in terms of bar?? 1.6??
 

·
Registered
Joined
·
1,362 Posts
I always thought it was about 1.3 max on the standard gasket, but with other factors involved, i.e, engine temps etc. I would of thought how well your car has been mapped determines how long it will last. Too lean and cylinder temps and pressure goes up, and thats not really a good thing, least of all your head gasket

I'm sure someone knows better. I heard the pistons can be a weak point too.

Anyone else wanna shed some light on this?

Oh yeah, did you find out anything about the Tech Tom? I'd like to know more about mine. My car seems to run crap from cold till the moment the tech toms oil temp hits 60 deg.

Would like to know more about it

Hope your good though Alex mate
 

·
Registered
Joined
·
106 Posts
700 whp, 2 bar pump gas no probs.
Det/ abnormal combustion etc blows gaskets.
Obviously good insurance when pushing the limits but not necessary for majority of applications.
Jason
 

·
Registered
Joined
·
2,464 Posts
Hi Jason, I am sure I've discussed this with Rob before but still for piece of mind - what do you think is a safe point for an RB25? I run mine on 14-15psi/270-280kw @ wheels and have been for the last 2/3 years without drama like that (aside from unrelated ignition etc issues). Now I am happy I have got everything else sorted I am looking at doing a dyno tune to 18psi for "special occasions". We always keep the tune very safe, have never had det on the dyno and figure its been fine on the track and strip otherwise it'd not be still going strong :)

Do you think that'd be safe enough on stock HG/internals for a few power runs and hitting the strip?

Cheers
 

·
Registered
Joined
·
6,560 Posts
Me and Jase have run 25+psi with totally stock internal RB25s (around 340-350wkw), don't worry so much Lith!! just go for it, I'll have your backup RB30 here waiting, lol. :)

Rob
 

·
Registered
Joined
·
106 Posts
Hi Lith. As Rob said. At 18 psi you will be fine, provided no det and even then piston will be damaged before head gasket lets go!
Would suggest 300Kww to be the safe limit of the standard rod bolts though on chassis dyno(approx 330kw on hub dyno) 250Kww will net high 11s with std gtrs and link G4 on the quater.
 

·
Registered
Joined
·
2,464 Posts
Thanks guys :) Yeah I expect the result to be around 310wkw on the hub dyno, would be nice to try and give the 11s a touch on a stocker motor.

Haha cheers Rob ;)
 
1 - 9 of 9 Posts
Top