Head Gasket Installation - SR20DET - Page 2 - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

s14unimog · 11-05-2009, 08:23 AM

Quote:

Originally Posted by ericb382

The FSM gives procedures for a stock HG. We are talking about aftermarket HG's. I hope you wouldn't use the FSM's torque specs when torquing down ARP head studs.... Same concept.

Like I mentioned earlier, I called Apexi (the manufacturer of my HG) and asked them what they recomend for THEIR HG. They said not to use anything. I didn't and it worked perfect. Like I also mentioned earlier, there are some instances where I would deviate from their recomendations to match a specific application, but in a perfect world (head, block and front cover machined) you don't need it.

I am very aware of the differences between this installation and that of a standard OEM head gasket. With that said, I would think a MLS headgasket could use the additional "support" to seal that area. I spoke with Cosworth USA about my application and they recommended the use of liquid gasket on the front cover. I am not the kind of individual to do motor work without extensive research.

I appreciate your input and can end this debate with a few more words.

For all who read this write up:
If you feel you don't need liquid gasket and are confident that it will not leak, then don't use it. If you feel that you might need it, use it.

ericb382 · 11-05-2009, 12:54 PM

So cosworth probably doesn't put the "additive" on their HG's that Apexi does. I was told by apexi that they put an additive on their HG so you don't need RTV. This is a perfect example of why you should contact the mfg our your particular parts for their recomendations, because every brand does things a little different.

s14unimog · 11-06-2009, 02:15 PM

^ good point! That's an interesting bit of information about Apexi; I never knew that.

s14unimog · 11-13-2009, 08:00 AM

just a bit of closure. I've put about 30 miles on the car since I've done the head gasket and all seems to be well. I will do a leak down soon and post those results.

ericb382 · 11-13-2009, 01:39 PM

Quote:

Originally Posted by s14unimog

just a bit of closure. I've put about 30 miles on the car since I've done the head gasket and all seems to be well. I will do a leak down soon and post those results.

And a bit more closure for the topic.... I leakdown tested mine after my HG install with 0% leakage (shitty harbor freight tester tended to stick on 0 then shoot all the way to 100 when there was a problem.) I drove it untill my fuel pump went out during HPDE and melted my CP piston. Yes, the HG held better than the piston. Don't take this as a bash on CP at all, I love them, it was just lean as shit, no piston will hold that.... but the HG did.

s14unimog · 11-16-2009, 11:02 AM

That is no bueno, I had a "less than intelligent" roommate that had the turbonetics single kit on his 350Z with some random reflash (bought the kit used and not complete). Long story short, he had no wideband and has gone through 3 motors (from lack of understanding the problem) and in one of those, destroyed a set of CP pistons before any head gasket issues. Without confident and correct monitoring of your A/F's you are almost guaranteed to burn your pistons down.

"The correct air/fuel ratio balance of an engine is most critical for piston longevity, durability and proper engine operation. The combination of too much fuel or too little air will have the same result – thermal growth or piston crown erosion."

Engine Builder Magazine - Heavy Duty Technology: Piston Failure Analysis
By Dennis Nail

I've been draggin ass about doing a leak down test, but I've run the motor fairly hard with no issues.

11-06-2009, 02:15 PM	#33
s14unimog Zilvia FREAK! Join Date: Dec 2003 Location: under my car Age: 23 Posts: 1,466 Trader Rating: (7) Rides Gallery: s14unimog	^ good point! That's an interesting bit of information about Apexi; I never knew that. __________________ Fuking ginger bread man stole my wallet... SHIFT*lock_slide to side d3m3rs0n: if i have a baby im naming it Brandons Fault Emerson

11-13-2009, 08:00 AM	#34
s14unimog Zilvia FREAK! Join Date: Dec 2003 Location: under my car Age: 23 Posts: 1,466 Trader Rating: (7) Rides Gallery: s14unimog	just a bit of closure. I've put about 30 miles on the car since I've done the head gasket and all seems to be well. I will do a leak down soon and post those results. __________________ Fuking ginger bread man stole my wallet... SHIFT*lock_slide to side d3m3rs0n: if i have a baby im naming it Brandons Fault Emerson

11-16-2009, 11:02 AM	#36
s14unimog Zilvia FREAK! Join Date: Dec 2003 Location: under my car Age: 23 Posts: 1,466 Trader Rating: (7) Rides Gallery: s14unimog	That is no bueno, I had a "less than intelligent" roommate that had the turbonetics single kit on his 350Z with some random reflash (bought the kit used and not complete). Long story short, he had no wideband and has gone through 3 motors (from lack of understanding the problem) and in one of those, destroyed a set of CP pistons before any head gasket issues. Without confident and correct monitoring of your A/F's you are almost guaranteed to burn your pistons down. "The correct air/fuel ratio balance of an engine is most critical for piston longevity, durability and proper engine operation. The combination of too much fuel or too little air will have the same result – thermal growth or piston crown erosion." Engine Builder Magazine - Heavy Duty Technology: Piston Failure Analysis By Dennis Nail I've been draggin ass about doing a leak down test, but I've run the motor fairly hard with no issues. __________________ Fuking ginger bread man stole my wallet... SHIFT*lock_slide to side d3m3rs0n: if i have a baby im naming it Brandons Fault Emerson

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11-05-2009, 12:54 PM	#32
ericb382 Zilvia Member Join Date: Oct 2005 Location: Flagstaff, Az Posts: 212 Trader Rating: (4)	So cosworth probably doesn't put the "additive" on their HG's that Apexi does. I was told by apexi that they put an additive on their HG so you don't need RTV. This is a perfect example of why you should contact the mfg our your particular parts for their recomendations, because every brand does things a little different.