924Board.org

AppleBit · Joined: 16 Nov 2002 Posts: 1516 Location: Minneapolis, MN

When you put a thinner head gasket on an the 924 NA, that advances or retards timing?

I am looking at putting on the Porsche 924 Turbo headgasket on my car.... this is why I ask....

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Alex Roy · Guest

Well, from looking at it, it retards it.

AppleBit · Joined: 16 Nov 2002 Posts: 1516 Location: Minneapolis, MN

I am wondering the thickness difference, if it really increases a 1/2 point and how much it will change the cam timing...

again, doesn't matter since I have vario cam timing... but curious ya know

- Jon

Benski · Guest

I did the calculations once. I can't remember but it wasn't quite 0.5 compression points. It was more like 0.1 or 0.2. Not worth the effort IMO but maybe worthwhile if you have to replace the headgasket anyway.

TroyDest · Guest

Hey Jon,

I just took apart an '81 931 engine. The original head gasket (Victor Reinz) measures 0.064 inches. How thick is your 924 gasket? By the way, the cheapest 931 gasket I've found so far is $150!!

-Troy

-nick · Guest

woah! you're looking in the wrong places. i picked mine up for about $30 at my somewhat local shop- gicp.com in MA. it was also a reinz i believe.

-nick

AppleBit · Joined: 16 Nov 2002 Posts: 1516 Location: Minneapolis, MN

I'll check on the NA thickness...

I picked up just the head gasket from Auto Atlanta for just under $50....

Should be in today....

TroyDest · Guest

Well Jon,

Did you get your head gasket? Who is the manufacturer, what is the part number on the gasket, and how thick is it? By the way, how thick was your NA gasket? Thanks, Troy

eturbo924 · Guest

Bob Dodd down on the 931 list sells a complete head gasket kit for that cost
Right about $50.... complete kit. I purchased it and it is the best I have seen. He also send it over night when I needed it real quick. great service and price and he is a 924.org lister!

Eric

Zuffen · Posted: Tue Mar 19, 2002 5:45 am Post subject:

The gasket set I sell is for the 924NA....I can't recall what the difference is but the ports are sized and placed different. Which could all be modified I quess should one want to.

_________________
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

AppleBit · Joined: 16 Nov 2002 Posts: 1516 Location: Minneapolis, MN

Are you sure the gasket ports are located elsewhere? I heard you could do a few modifications to a 924 Turbo head and just bolt it right onto the NA block (yeah, I know the pistons would need to be higher compression...but...)

I hope this gasket works... dont want to spend more than I need to right now....

Zuffen · Posted: Tue Mar 19, 2002 8:22 am Post subject:

To clarify

the water ports are what is different between the two gaskets.

The blocks are identical and the head I believe is real close. There are some water passages on the 924NA and not on the 931. I think the holes are smaller on the 931 gasket. I guess Ineed to compare and take pictures . I've got a GTR gasket a 931 gasket and a 924 gasket. I don't have each brand of 924 or 931 gasket made. And there will be differences.

What are you needing Apple bit, which car?

_________________
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

AppleBit · Joined: 16 Nov 2002 Posts: 1516 Location: Minneapolis, MN

I heard you can put a 931 gasket on the 924 NA and since it is thinner, you can raise the compression then..........

-nick · Guest

some of the water jackets are a little different between the 931 and 924na gaskets.

from what i've found the difference is actually a desireable one for the na. the change is water jacket hole sizes and placements is to keep the head temperatures more consistent from one end to the other. the difference is probably only noticeable in longevity.

as for the thickness- a few thousands is not going to change your crank/cam timing anymore than expansion/contraction from temperature changes on the 3ft. of rubber timing belt will change the timing.

i'll get around to a compression test on mine eventually and hopefully end the debate on whether the compression goes up with the 931 gasket. stock 9.3:1 compression is supposed to read 156psi i belive. so anything above that on my practically new motor will be due to the 931 headgasket. regardless of compression, the 931 gasket will offer better longevity on the na engine due to the water jacket changes.

regards,
-nick

AppleBit · Joined: 16 Nov 2002 Posts: 1516 Location: Minneapolis, MN

I think that a 8.5:1 compression engine can read 160 psi sometimes, and other times it can read 120 psi... the reason it is different is cam timing... so, that test will say nothing...