Sr headgasket Q's - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

idamaster · 11-12-2009, 06:58 PM

Im about to pull my head right now and I wanted to get a thicker headgasket. Ive been told to go with a 1.5 but what are the pros/cons of a 1.5 and a 1.1 or does it not matter at all? Q #2: Is there any major benifit from ARP head studs for higher boost?

okisrniju · 11-12-2009, 07:15 PM

I was wondering the same thing. I don't plan on boosting past 1.2 but I do have a 1.2 mm headgasket. Someone told me that I'll have to shave the head if I get a thicker headgasket for compression. Is that true?

idamaster · 11-12-2009, 08:07 PM

Quote:

Originally Posted by okisrniju

I was wondering the same thing. I don't plan on boosting past 1.2 but I do have a 1.2 mm headgasket. Someone told me that I'll have to shave the head if I get a thicker headgasket for compression. Is that true?

If you get your head machine you need a thicker head gasket to compensate for the loss of metal. Just my guess.

HYPNOTIK · 11-14-2009, 05:27 AM

Unless you have a reason to lower your compression there is no reason to get a thicker headgasket. Especially if your running stock bottom end I would not lower the compression, stock pistons are 8.3:1, if anything I'd go with a smaller headgasket to raise compression. If you have the head shaved and it's still within spec there is still no reason for a thicker headgasket. If your head is shaved enough that you need to compensate with a thicker headgasket then it's time for a new head.

Def get some ARP studs or at the very minimium some new stock head bolts. Don't reuse your stock bolts, they stretch.

It's a good idea to get the head shaved when you replace the head gasket with a metal one to ensure a perfectly flat mating surface so that you get a good seal.

You should be fine with the 1.1mm.

idamaster · 11-14-2009, 08:34 AM

The reason I want to get a thicker head gasket is because I want to turn my boost up to about 16 psi. With supporting mods of course.

HYPNOTIK · 11-14-2009, 09:01 AM

You still don't need a thicker headgasket. I plan on running 1.5bar w/ 9:1 compression.

idamaster · 11-14-2009, 09:31 AM

Well is there a loss of power with a thicker headgasket at stock boost? Just a random question.

ericb382 · 11-14-2009, 02:02 PM

Yes. IMHO get a .8 and crank the boost.

idamaster · 11-25-2009, 10:07 AM

Do the headstuds go on first or do you put the head on THEN put the headstuds on?

VNG704 · 11-25-2009, 10:21 AM

Follow the FSM. Acronym for Factory Service manual. If you don't have one, the .pdf file is free for downloading online. Answers most your DIY questions you'll have.

I put the head on first.

HaSo240sx · 11-25-2009, 10:22 AM

I would do the head studs and on the s14 sr motor the headgaskets f up on higher boost, but sence your pulling the head might as well doit i would suggest the apexi...

idamaster · 11-25-2009, 12:29 PM

Quote:

Originally Posted by HaSo240sx

I would do the head studs and on the s14 sr motor the headgaskets f up on higher boost, but sence your pulling the head might as well doit i would suggest the apexi...

I already have arp studs. I was asking if they go on before I put the head or after.

Sileighty_85 · 11-25-2009, 02:33 PM

Quote:

Originally Posted by HYPNOTIK

, stock pistons are 8.3:1, .

Stock Compression Ratio is 8.5:1, just wanna clear that up

Running a thicker head gasket is not a bad thing, it lowers the chances of detionation at high boost compared to a Higher compression boosted engine, But really its all in the tune, if you can get a good tune your safe.

Im running a 1.5 mil PE head gasket boosting 21psi with no issues.

slamn240 · 11-26-2009, 10:03 PM

i put them on after you put the head on. that is what ii did when i use to builted sr's for sr motorcars

xdumbxguyx · 11-26-2009, 10:16 PM

put the head on first then the arp studs
make sure to put a light layer of silicone over the oil pump area where the head gasket seats on
1.1mm headgasket should be fine for ur appication

11-12-2009, 06:58 PM	#1
idamaster Zilvia Member Join Date: Oct 2009 Location: Louisiana Posts: 166 Trader Rating: (3) Feedback Score: 3 reviews	Sr headgasket Q's Im about to pull my head right now and I wanted to get a thicker headgasket. Ive been told to go with a 1.5 but what are the pros/cons of a 1.5 and a 1.1 or does it not matter at all? Q #2: Is there any major benifit from ARP head studs for higher boost?

11-14-2009, 05:27 AM	#4
HYPNOTIK Zilvia Addict Join Date: Apr 2008 Location: Pisa, Italy Posts: 700 Trader Rating: (3) Feedback Score: 3 reviews	Unless you have a reason to lower your compression there is no reason to get a thicker headgasket. Especially if your running stock bottom end I would not lower the compression, stock pistons are 8.3:1, if anything I'd go with a smaller headgasket to raise compression. If you have the head shaved and it's still within spec there is still no reason for a thicker headgasket. If your head is shaved enough that you need to compensate with a thicker headgasket then it's time for a new head. Def get some ARP studs or at the very minimium some new stock head bolts. Don't reuse your stock bolts, they stretch. It's a good idea to get the head shaved when you replace the head gasket with a metal one to ensure a perfectly flat mating surface so that you get a good seal. You should be fine with the 1.1mm. __________________

11-14-2009, 09:01 AM	#6
HYPNOTIK Zilvia Addict Join Date: Apr 2008 Location: Pisa, Italy Posts: 700 Trader Rating: (3) Feedback Score: 3 reviews	You still don't need a thicker headgasket. I plan on running 1.5bar w/ 9:1 compression. __________________

11-26-2009, 10:16 PM	#15
xdumbxguyx Zilvia FREAK! Join Date: Apr 2005 Location: 626 Posts: 1,189 Trader Rating: (23) Feedback Score: 23 reviews	put the head on first then the arp studs make sure to put a light layer of silicone over the oil pump area where the head gasket seats on 1.1mm headgasket should be fine for ur appication __________________ infinitwheels.com pitgarage.net

11-12-2009, 07:15 PM	#2
okisrniju Leaky Injector Join Date: Nov 2008 Location: Minot, North Dakota Age: 41 Posts: 72 Trader Rating: (11) Feedback Score: 11 reviews	I was wondering the same thing. I don't plan on boosting past 1.2 but I do have a 1.2 mm headgasket. Someone told me that I'll have to shave the head if I get a thicker headgasket for compression. Is that true?

11-14-2009, 08:34 AM	#5
idamaster Zilvia Member Join Date: Oct 2009 Location: Louisiana Posts: 166 Trader Rating: (3) Feedback Score: 3 reviews	The reason I want to get a thicker head gasket is because I want to turn my boost up to about 16 psi. With supporting mods of course.

11-14-2009, 09:31 AM	#7
idamaster Zilvia Member Join Date: Oct 2009 Location: Louisiana Posts: 166 Trader Rating: (3) Feedback Score: 3 reviews	Well is there a loss of power with a thicker headgasket at stock boost? Just a random question.

11-14-2009, 02:02 PM	#8
ericb382 Zilvia Member Join Date: Oct 2005 Location: Mesa, Az Posts: 293 Trader Rating: (4) Feedback Score: 4 reviews	Yes. IMHO get a .8 and crank the boost.

11-25-2009, 10:07 AM	#9
idamaster Zilvia Member Join Date: Oct 2009 Location: Louisiana Posts: 166 Trader Rating: (3) Feedback Score: 3 reviews	Do the headstuds go on first or do you put the head on THEN put the headstuds on?

11-25-2009, 10:21 AM	#10
VNG704 Zilvia FREAK! Join Date: Dec 2008 Location: Wisconsin Posts: 1,575 Trader Rating: (17) Feedback Score: 17 reviews	Follow the FSM. Acronym for Factory Service manual. If you don't have one, the .pdf file is free for downloading online. Answers most your DIY questions you'll have. I put the head on first.

11-25-2009, 10:22 AM	#11
HaSo240sx Leaky Injector Join Date: Apr 2009 Location: Knoxville, Tn Age: 35 Posts: 60 Trader Rating: (0) Feedback Score: 0 reviews	I would do the head studs and on the s14 sr motor the headgaskets f up on higher boost, but sence your pulling the head might as well doit i would suggest the apexi...

11-26-2009, 10:03 PM	#14
slamn240 Zilvia Addict Join Date: Feb 2007 Location: SFV Age: 38 Posts: 856 Trader Rating: (23) Feedback Score: 23 reviews	i put them on after you put the head on. that is what ii did when i use to builted sr's for sr motorcars