2008+ superjet compression

[dave787]

I've heard a few times the 08+ superjets have 20+ psi higher compression stock than the older SJ's. Is there any official truth behind this or is it just a rumor i've heard a few times? my compression checker may be inaccurate but it said i have 153psi in both on my 08. what have yall heard and what did all of yall's have stock?

 

[ItsRixter]

I've heard a few times the 08+ superjets have 20+ psi higher compression stock than the older SJ's. Is there any official truth behind this or is it just a rumor i've heard a few times? my compression checker may be inaccurate but it said i have 153psi in both on my 08. what have yall heard and what did all of yall's have stock?

The superjet motor has not changed in 13 years...stock is 150 psi

 

[dave787]

that's what I thought too, but people say the head gasket is a different part number and that it's thinner on the 08. anyone out there seen higher compression when testing their stock ski with a reliable tester?

 

[brett]

ive heard its supposed to be 20 psi more, so 170? but its probably just rumors

 

[directbuy]

Mine showed 155 with a stock head and good tester. I have also heard that the gasket was a bit thinner on the 08's.

 

[SUPERTUNE]

Just rumors, all the same!

 

[Wave ninja]

I tested my stock 2016 a year old and was showing 175 and 180psi

 

[mikidymac]

2007 and 2017 both show the exact same part numbers for head and head gaskets. There can be a big variation in compression testers.

 

[bored&stroked]

2007 and 2017 both show the exact same part numbers for head and head gaskets. There can be a big variation in compression testers.

Considering this was posted in 2009 you would have to compare 2009 to 1999 to get where they were coming from.

 

[mikidymac]

Considering this was posted in 2009 you would have to compare 2009 to 1999 to get where they were coming from.

WOW, I didn't realize it was such an old resurrected thread.

But 1999 and 2008 still show same part numbers.

 

[theVetteman3]

I have had two mint 2009s with low hours and they were both at 150-155 psi.

 

[mikidymac]

I guess I should ask since this is active again.... I have a 1996 head that says "64U" but it looks different than the other heads as it doesn't have the 2 dimples on the MAG cylinder top like the others. Did they make a change at some point?