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pgermond
December 23rd, 2007, 09:29 PM
After four years I have finally blown the passenger-side exhaust gasket. Looking through previous threads on the subject, I see that the most recent threads recommend the copper gaskets. Is this still the consensus?

I have been reluctant to climb under the car as I can't remember if I used anti-seize on the header bolts.... if not, I'm afraid I'm going to snap one off - which will require removal of the head. At any rate, it will probably go up stands tomorrow and receive a very good soaking of penetrating solution(s) over the next two days, with surgery taking place the day after Christmas.

Any thoughts on the best type of header gasket will be appreciated. Thanks

davebetts
December 24th, 2007, 05:48 AM
Been there, done that - twice. I think the most important thing to remember, I'm talking from my lack of experience here, is to retighten after the new gaskets are installed and run the engine through the heat cycles. I tried to use the copper gaskets (Summit has) but the exhaust bore is not large enough. Wish I could find them in copper. I'm running Edelbrock aluminium heads. Installed Felpro instead, first set burned back out after a season (I didn't retighten as advised). You can tell they are bad because when you run the RPM's up, let off for an upshift, there's a loud backfire noise. I've been told that's the oxygen leaking to the unburned fuel in the exhaust, and it ignites it - bang! The second set is still on the engine, no problems. You have to tighten as less 3 to 4 times and then the bolts stop turning. Would also advise to just take the bolts out, slip the new gaskets in and reinsert and tighten. Taking evrythind down (my first time) made it too difficult to line everything up and still get a bolt started. Good luck!

Naumoff
December 24th, 2007, 05:54 AM
Copper gaskets are the way to go and I have had great luck with them.
You have to use copper high temp sealer with them. Tighten once and when I check them they are all still tight.

Dave, you must have some serious work done on the exhaust ports. I have the CNC heads from SA and the exhaust ports are huge. Nothing a little trimming wouldn't take care of.

pgermond
December 24th, 2007, 09:02 AM
I have the Edelbrock aluminium heads also.

pgermond
December 24th, 2007, 09:33 AM
Tony - do you have a part # for the copper gaskets? I'm looking at SCE-4034 (http://store.summitracing.com/partdetail.asp?autofilter=1&part=SCE%2D4034&N=700+4294886211+4294908331+4294925081+4294908395+ 4294840105+115&autoview=sku) or SUM-111435 (http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM%2D111435&N=700+4294886211+4294908331+4294925081+4294908395+ 4294840105+115&autoview=sku). Both Summit and SCE offer a couple different part numbers.

Thanks!

Naumoff
December 25th, 2007, 06:06 AM
Phil,
I am using the SCE-4034.

Jeff 427
December 26th, 2007, 04:14 AM
Phil,
I also used the Summit copper gaskets; I have the aluminum Edelbrock heads on my SA406 and they fit fine. I did use ARP 12 pt. SS bolts with never seize.

nolastyankee
December 26th, 2007, 08:51 AM
Phil,
One more option to consider, I installed the Percy's aluminum gaskets. They are much thicker than the copper - it is two plies of material that are about 1/16" before installation. This extreme was necessitated by the not-so-straight flanges on my headers. The aluminum material is really soft and totally conforms to the head and header upon installation. I would highly recommend if you have imperfect surfaces. They do not require sealant.

Tony Radford
December 26th, 2007, 08:51 AM
After I destroyed my first set (two engines ago) I purchased copper gaskets. I used a dremmel tool to hog them out as my SA engine had a fair amount of port work. I haven't had any problems since.

pgermond
December 26th, 2007, 09:13 AM
Thanks for the info guys. Just ordered the SCE copper gaskets from Summit before the last two replies were posted. The input is very much appreciated.

twanita
December 26th, 2007, 06:40 PM
hey phil, i'm always blowing them out so i'll be interested to see how yours hold up.

one trick i found was to cut the gasket in half so there are 2 ports per gasket instead of 4. it makes them a lot easier to replace because you can leave half the bolts in and just loosen them enough to slide the damaged half gasket out. when replacing the bolts on the damaged side they are much easier to start the threads because the header remains in place. just make sure they are all same type and thickness.

davebetts
December 27th, 2007, 08:46 AM
Wow, what a great idea, cut the gasket in half. I like that. Should save some knuckle skin.
Re: the port sizes of my engine. There are two sizes of gaskets available (in Felpro style), but only the smaller port size in copper. I bought the copper ones (from Summit) and tried to enlarge, but you loose the crimped sealing groove that the manufactured has punched into the perimeter of the port edges. As far as the port sizes, it's just Bill's (Southern Automotive) stroker 484 cu. in. I can measure and repost, with pictures, if anyone is interested.

pgermond
December 27th, 2007, 11:07 AM
Yes! I did use anti-seize - nothing broke!!!!! My started is wrapped with heat-reflective material so I had to pull the whole works to get at the bolts. The header won't drop all the way out of the car because of the location of my Canton overflow tank.

Just waiting for the postman to deliver the gaskets.

spd4me
December 27th, 2007, 05:27 PM
I've got a FIA with SA 396Stroker trick flow alum heads. When my gasket blew out I tried a copper but the openings were way to small. I used a Holly alum. Has large rectangle openings with square corners. Did alittle filing and they fit perfect. Because they are a two part material they conform very well to heads and headers. I check tightness about once a month just for something to do.
Bob

pgermond
December 28th, 2007, 05:10 PM
Well that was a major pain in the A$$!!!! The most difficult part of re-assembling was the starter (that top bolt drove me nuts). The SCE-4034 copper gaskets fit my Edlebrock mid-rise 427 head perfectly. SCE does make different port sizes, so maybe that has been an issue for others.
At any rate, it is done!!!


http://www.uniquecobra.com/gallery/files/1/3/1/5/PC280001_114013.JPG

ralphscott
December 29th, 2007, 03:44 AM
Congrats Phil, I'm sure in a couple of days you will find muscles you forgot you had.

Happy New Year!

Ralph