Show full size 924Board.org
Discussion Forum of 924.org
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
 Technical FAQ924 FAQ (Technical)   Technical924 Technical Section   Jump to 924.org924.org   Jump to PCA 924 Registry924 Registry

copper head gasket
Goto page 1, 2  Next
 
Post new topic   Reply to topic    924Board.org Forum Index -> 931 Tech.
View previous topic :: View next topic  
Author Message
crunchie 57  



Joined: 18 Mar 2004
Posts: 117
Location: Brisbane Australia

PostPosted: Fri Mar 16, 2007 7:56 pm    Post subject: copper head gasket Reply with quote

I need information on the use of Copper head gaskets.
After over a year, my engine is almost finished. Re-board to 87.5mm new forged custom pistons. Chrome-molly wrist pins. Stud kit. Reground crank. New big and little end bearings. Etc etc. I am up to the point of “o” ringing the block. There seems to be endless opinions as to the best way to do this i.e. ring the block only …ring the head only …ring the block and put a receiver groove in the head etc etc etc. What I would like is to hear from someone who has actually gone and used a copper head gasket and “o” ring (successfully) and what worked for them. I am thinking along the lines of a .9mm gasket with “o” rings in the block. I am looking for an end result that will allow me to run 15psi @ 8.5 – 1 CR. Also info on gasket glue.. coppercote, hylamar, 3 bond ????
Any info would be appreciated thanks.
Crunchie 57
_________________
78 924 N/A with 944 body kit (love this car)
79 924 NA - track car
81 924 Auto with 6V Buick
Back to top
View user's profile Send private message Send e-mail
-nick  



Joined: 16 Nov 2002
Posts: 2699
Location: Cambridge, MA

PostPosted: Sat Mar 17, 2007 3:17 am    Post subject: Reply with quote

Let me be the first to say - with head studs, an intercooler, and good tuning, I don't think you need o-ringing at 15psi. If you were going over 20psi, then I would worry about it. Even then, you could probably get away with o-rings + stock headgasket.

I've heard reports of water passages not sealing well under any circumstances with a copper gasket. It seems that cold weather is usually when they leak. I don't know that they're worth it for a street car.
_________________
1980 931S
15psi boost, MS-II, EDIS, 951 IC, custom intake, Ford 5.0L throttle body, Forge BOV, WB o2, G31 w/LSD, 964 wheels, 968 rear sway, Bilsteins, 200# Welt. springs. A laptop, and a partridge in a pear tree.
1991 964 C4 Cabriolet
Back to top
View user's profile Send private message Send e-mail Visit poster's website
endwrench  



Joined: 07 Dec 2002
Posts: 1629
Location: Victor, Montana

PostPosted: Sat Mar 17, 2007 7:13 am    Post subject: Reply with quote

I'm gonna second Nick. You may consider this gasket for extra insurance but I see no need for O-ringing at that boost level. Studs are #1 priority though.

http://www.horsepowerfreaks.com/price/Porsche/924/Cometic/Engine/Head_Gaskets

Todd
_________________
'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....
Back to top
View user's profile Send private message Send e-mail
-nick  



Joined: 16 Nov 2002
Posts: 2699
Location: Cambridge, MA

PostPosted: Sat Mar 17, 2007 7:18 am    Post subject: Reply with quote

^ cool That's new. Wish I knew about it last month! The price is only $25 more than the stock gasket.
_________________
1980 931S
15psi boost, MS-II, EDIS, 951 IC, custom intake, Ford 5.0L throttle body, Forge BOV, WB o2, G31 w/LSD, 964 wheels, 968 rear sway, Bilsteins, 200# Welt. springs. A laptop, and a partridge in a pear tree.
1991 964 C4 Cabriolet
Back to top
View user's profile Send private message Send e-mail Visit poster's website
leadfoot  



Joined: 11 Dec 2002
Posts: 2222
Location: gOLD cOAST Australia

PostPosted: Sat Mar 17, 2007 2:21 pm    Post subject: Reply with quote

cometic has a copper one in an 88mm bore...
http://www.cometic.com/catalogs/sportcompact.pdf
they might be able to do a triple layer steel otherwise...
ACL might be able to make you one, but they don't have a standard listing for a porsche...
Leadfoot
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...
Back to top
View user's profile Send private message Send e-mail
crunchie 57  



Joined: 18 Mar 2004
Posts: 117
Location: Brisbane Australia

PostPosted: Sat Mar 17, 2007 3:10 pm    Post subject: Reply with quote

Quote:


cometic has a copper one in an 88mm bore...
http://www.cometic.com/catalogs/sportcompact.pdf
they might be able to do a triple layer steel otherwise...
ACL might be able to make you one, but they don't have a standard listing for a porsche...
Leadfoot

I can get the copper gasket from ACL as they are 10 min from work and will cut anything as long as I can give them a pattern. cometic don't make the s/steel ones for 924 only copper

Quote:

I've heard reports of water passages not sealing well under any circumstances with a copper gasket. It seems that cold weather is usually when they leak. I don't know that they're worth it for a street car

the local guys recommend the use of 3 bond (a very high temp silicone) around all water and oil ways ... copper heats up and cools down (expands and contracts) quicker than steel or alloy... hence the leeking in cold weather.
as for using a stock head gasket the last one was only on for a short time and it was showing signs of failing arounf the flame rings ...It looked as though the fiber material did not go all the way in to the rings and they where flatening out.... they also stuck inside the bore at 86.5 and I am now out to 87.5 so not keen to use them
Decisions decisions
_________________
78 924 N/A with 944 body kit (love this car)
79 924 NA - track car
81 924 Auto with 6V Buick
Back to top
View user's profile Send private message Send e-mail
leadfoot  



Joined: 11 Dec 2002
Posts: 2222
Location: gOLD cOAST Australia

PostPosted: Sun Mar 18, 2007 6:12 pm    Post subject: Reply with quote

That's bizzare, they should measure 90mm inside diameter...
I'm at 88mm bore and went with the stock gasket, I've used both reinz and goetz head gaskets now and found the gasket inside diameter to be larger than the bore...
Will acl supply a multi layer steel gasket then??
Leadfoot
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...
Back to top
View user's profile Send private message Send e-mail
crunchie 57  



Joined: 18 Mar 2004
Posts: 117
Location: Brisbane Australia

PostPosted: Sun Mar 18, 2007 8:52 pm    Post subject: Reply with quote

Quote:
That's bizzare, they should measure 90mm inside diameter...
I'm at 88mm bore and went with the stock gasket, I've used both reinz and goetz head gaskets now and found the gasket inside diameter to be larger than the bore...
Will acl supply a multi layer steel gasket then??
Leadfoot

ACL can't make the cometic type steel gasket they can cut it but can't emboss it or stamp it together as the set up cost of the tooling is way to much. They can cut me a steel or copper to my specs but only as a single layer. the last stock gastet came in a ACL packet but they say they don't make them ???? seems some one is doing a bit of repackageing. I think it is still down in the shed somewhere I will dig it out and measure it
thanks to all for your help and advise
Crunchie 57
_________________
78 924 N/A with 944 body kit (love this car)
79 924 NA - track car
81 924 Auto with 6V Buick
Back to top
View user's profile Send private message Send e-mail
crunchie 57  



Joined: 18 Mar 2004
Posts: 117
Location: Brisbane Australia

PostPosted: Sun Mar 18, 2007 9:06 pm    Post subject: Reply with quote

Just had a thought on the old stock gasket.... .
Quote:
That's bizzare, they should measure 90mm inside diameter

the flame ring was squashing down because the gasket material did not go all the way in to the back of the ring....if they are supposed to be 90mm could be that the hole in the gasket was 90mm but it had smaller flame ring (cheap faulty gaskets repacked to look like good quality product) ACL packet but ACL don't make them???? Or am I just getting paranoid....

_________________
78 924 N/A with 944 body kit (love this car)
79 924 NA - track car
81 924 Auto with 6V Buick
Back to top
View user's profile Send private message Send e-mail
macBdog  



Joined: 16 Aug 2004
Posts: 1110
Location: Brisbane, Australia

PostPosted: Mon Mar 19, 2007 11:40 am    Post subject: Reply with quote

Don't have any good info about head gaskets but its good to see you are up to that stage Dave. Can't wait to see the motor when I make it out to your place one of these weekends! Cheers, Charles.
_________________
1979 931 with a 350 chev
1973 911E with EFI
p-talk wrote:
I'm still convinced the word 'Porsche' makes people crazy in all kinds of ways
Back to top
View user's profile Send private message Visit poster's website
crunchie 57  



Joined: 18 Mar 2004
Posts: 117
Location: Brisbane Australia

PostPosted: Mon Mar 19, 2007 12:17 pm    Post subject: Reply with quote

Quote:
Don't have any good info about head gaskets but its good to see you are up to that stage Dave. Can't wait to see the motor when I make it out to your place one of these weekends! Cheers, Charles.

Hey when did you buy a 911??? got to have a look at that
_________________
78 924 N/A with 944 body kit (love this car)
79 924 NA - track car
81 924 Auto with 6V Buick
Back to top
View user's profile Send private message Send e-mail
Tigger937  



Joined: 11 Apr 2004
Posts: 906

PostPosted: Thu Mar 22, 2007 4:28 am    Post subject: Reply with quote

-nick wrote:
Let me be the first to say - with head studs, an intercooler, and good tuning, I don't think you need o-ringing at 15psi. If you were going over 20psi, then I would worry about it. Even then, you could probably get away with o-rings + stock headgasket.

I've heard reports of water passages not sealing well under any circumstances with a copper gasket. It seems that cold weather is usually when they leak. I don't know that they're worth it for a street car.


That scares me. Anyone hear of problems with the stock head gasket using Raceware Head Studs at 20+ psi?

endwrench wrote:
I'm gonna second Nick. You may consider this gasket for extra insurance but I see no need for O-ringing at that boost level. Studs are #1 priority though.

http://www.horsepowerfreaks.com/price/Porsche/924/Cometic/Engine/Head_Gaskets

Todd


Nothing for the 931?
_________________
1981 931 (Concours)
1982 931 (Daily Driver)

"Think outside the box"
Back to top
View user's profile Send private message
-nick  



Joined: 16 Nov 2002
Posts: 2699
Location: Cambridge, MA

PostPosted: Thu Mar 22, 2007 4:39 am    Post subject: Reply with quote

Even with the copper coat headgasket dressing, there are plenty of stories of the water passages not sealing with a copper headgasket.

Stock gaskets either come from Victor Reinz or Goetze. They are the same 931 or 924na.
_________________
1980 931S
15psi boost, MS-II, EDIS, 951 IC, custom intake, Ford 5.0L throttle body, Forge BOV, WB o2, G31 w/LSD, 964 wheels, 968 rear sway, Bilsteins, 200# Welt. springs. A laptop, and a partridge in a pear tree.
1991 964 C4 Cabriolet
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Tigger937  



Joined: 11 Apr 2004
Posts: 906

PostPosted: Thu Mar 22, 2007 4:44 am    Post subject: Reply with quote

-nick wrote:
Even with the copper coat headgasket dressing, there are plenty of stories of the water passages not sealing with a copper headgasket.

Stock gaskets either come from Victor Reinz or Goetze. They are the same 931 or 924na.


It was my understanding the 931 has larger/additional water passages?
_________________
1981 931 (Concours)
1982 931 (Daily Driver)

"Think outside the box"
Back to top
View user's profile Send private message
emoore924  



Joined: 13 Apr 2004
Posts: 2798

PostPosted: Thu Mar 22, 2007 4:51 am    Post subject: Reply with quote

I thought head gaskets were not the same n/a to turbo. Something about changes to the rear water passage being blocked off on the turbo to improve cooling circulation (cut off passage=better circulation, go figure) and some difference in the composition of the fire sealing ring or something. And I thought there was a price diff as well -- n/a about $90, turbo about $140.

I have a couple gaskets lying around and I think they are different in a couple of ways. I'll have to look a little more closely and see what's different, and see whether they actually have different part numbers rather than supercession part numbers. I'll try and post back after I take a look.

I'm pretty sure I have the turbo gasket on my n/a but for the life of me I can't recall why we went with it...
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    924Board.org Forum Index -> 931 Tech. All times are GMT + 11 Hours
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group