924Board.org

[Rick MacLaren]

What about the reverse?
Dumb question: Is there any advantage, besides cost, to installing a 924 gasket on the 931? Maybe lowering your compression on the 931 (i.e., gas mileage) before turbo kicks in, and then having the compression raised really high when you kick in the turbo? Maybe this sounds stupid, but they used to actually try to lower the base compression on of the stock engine on turbocharged cars...

[larso]

well the turbo gasket is actually a couple bucks cheaper... such as at germanparts.com

The 931 gasket is stronger...so i would use it or a thick copper one if u want less compression.

u could also dremel out your comb chamber in your head to lower comp.

less compression is good for lotsa boost but it all depends what u want, town driving, racing driving, stop lights or no stop lights.

[ This Message was edited by: larso on 2001-09-02 14:23 ]

[Joes924]

Well its a horsepower gain though. Ive had my motor overheat before and it didnt warp so I think its a good on to go for really

[-nick]

hey guys-
one advantage of the 931 gasket is that it has a better design for coolant flow. the holes in the gasket are a little different than the na and the coolant will dissapate heat more efficiently.

and i agree with Lars- i don't think .010" thicker or thinner on the head gasket is going to knock the cam/crank timing off much. as he said, probably no more than what happens when the belt is hot compared to being cold.

the copper gaskets do conduct heat better. but this makes the head _less_ prone to warping. when the head and the block are different temps, warping is more likely to occur. the problem with copper gaskets is that they can be difficult to get to seal as they don't conform to surface imperfections as well as a softer gasket. the copper gaskets are also reusable, which is nice.

i don't know how much of a hp difference the slight increase in comp gives, but i don't think it's much. i've got a thinner copper gasket, but i put it on the same time as a set of headers. between the two there was an increase!

hope this helps. the place that makes copper gaskets for 924's has a nice online faq - http://www.scegaskets.com

-nick

[Rick MacLaren]

Nick: So you noticed an increase in speed from using the 931 head gasket?

[-nick]

Rick-
it's hard to say if it was just the gasket. i switched from the cast iron manifold to headers at the same time. between the two there was certainly an increase. but the gasket alone?

temp gauge readings didn't change due to the updated coolant ports in the gasket either. but i wouldn't really expect to see that much of a difference, just would expect it to heat and cool more evenly across the head.

regards
-nick

[924RACR]

make sure you get a 931 head gasket... I just put on a gasket from a 931 head gasket set, Victor Reinz brand, it's no different than the one I took off... for thickness or hole layout...

now the engine's running again, but like crap, I believe due to a pinched fuel return line...

This sucks... who ever said racing was all glory?!? sometimes I really just hate it... but keep hoping it'll improve... and one day that I'll make it out to the track again...

real bummer, got the car's suspension set up perfectly last night... but didn't get to bed till 1... now I'm supposed to be loaded on the trailer and ready to go to the track, but the car won't run right...

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[Zuffen]

depending on brand the only difference between a 931 gasket and a 924NA gasket is that the 931 has smaller coolant holes about 1/8 versus 1/4. The metal webbing between the cylinders seems longer but I'm comparing between two brands. Victor Reinz and Goetze

Just so you guys know, a GTR head gasket is the same a 931 gasket.

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

[larso]

I can get goetze gaskets for about 45US at my local store here, I bought a reinz though, after reading 924.org and hanging out with some guys with pointy hats on and burning crosses. 67 plus customs and shipping making it about $90 when i had my 931.

So twice as much for the Reinz.

Now did I waste my money? I didn't buy goetze because of the Nazi "porsche oem parts" emphasis that 924.org had that i stricly followed. Sometimes I feel part of a cult.
But Bobby do u think the goetze ones are just as good.

[ This Message was edited by: larso on 2001-09-08 16:55 ]

[eturbo924]

Hey make sure you put some of these questions on the 931 section below. Bob had a lot of information on these cars..... also a lot of good parts!

Eric
http://www.geocities.com/eturbo924