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Discussion Starter #1 (Edited)
OK, so I have searched the Forum for an answer and found so many different opinions that I thought I would post and hope someone will have had my same set-up and found the correct fix. I have a Gen-1 SBC and both headers are leaking. Originally I used the header gaskets that came with the Summit headers. I tried the "Percy's Seal-4-Good" Header Gaskets Below:
http://www.summitracing.com/parts/php-66012/overview/make/chevrolet
NO LUCK.....Re-Torqued 3 times without a good result.

I have new AFR 180 Heads and new Summit Headers. What would be the best NEXT attempt gasket to use for a potential good seal? Thanks, Jack
 

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I gave up and just consider it part of my "pre-flight" routine that I go around and tighten up header bolts before I hit the road on weekend cruises. Just not ready to spend the $$ on those locking header bolts yet. Never had this problem on any other car that I ran headers on and didn't have the problem on this car 20 years ago when I was drag racing it. Go figure!!

Mark
 

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I gave up and just consider it part of my "pre-flight" routine that I go around and tighten up header bolts before I hit the road on weekend cruises. Just not ready to spend the $$ on those locking header bolts yet. Never had this problem on any other car that I ran headers on and didn't have the problem on this car 20 years ago when I was drag racing it. Go figure!!

Mark
You always have to retighten header bolts after the gasket takes a set from the many heat cycles. That being said I did mine a few times and now they stay tight. I always run the FelPro blue header gaskets and I throw away the gaskets(white ones) that usually come with the headers. It's not the bolts coming loose as it is the gasket taking a set and then the bolts are left loose after that.

FelPro #1404
 

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Like was said, I use the Felpro blue ones. I also am not afraid to use small port gaskets to ensure the tube makes full contact with the gasket. I only have 1 5/8 headers on the car, and the gaskets recommended by AFR were too big and just a tiny part of the gasket was sealing. Well, it burned through pretty quick. Maybe 1 3/4 headers would have sealed better on those.
 

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I am going through this as we speak. AFR 195 heads, JW nova 1-5/8" headers. tried the felpro 1404 gaskets had leaks on every port. A straight edge showed the flange and tubes to be pretty far out of wack. Had the header welds sanded flat on a belt sander and tried the Percy's, same deal. Pulled the Percy's out and noticed that the ports on the gasket are much taller than the ports on my heads. Percy advertises 1.5" x .1.5" but the actually measure 1.65 tall. Today I bought a new set of fel pro 1404 gaskets which match the exhaust ports perfectly and tried putting a bead of ultra copper on both sides of the gasket. I am letting it cure over night and will report back tomorrow.
 

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The cheap white ones can put in water overnight to swell them. Then put on as usual, run it till its hot. Then let it cool all the way down and retighten. Also another way is the fel pro copper gasket silicone. Coat both sides of header gasket, hand tighten only. Let it setup overnight, then tighten down. The silicone makes its own formed gasket this way, so if your flange is off some it fills in the gap. Worked on my Rat Rod.
 

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My 194 had chronic exhaust leak problems at the block. I blame both the fact that it's a 50-year-old engine that's never been out of the car and the modified intake and exhaust manifolds I've put on.

Anyway, went through 3 gaskets of varying quality and they all eventually started leaking within a month. Spent the extra $$ and got the super thick Remflex gasket and now, almost a year later, still no leak. In fact, it's more quiet than it was when stock.

Think what you'd need would be here:
http://catalog.remflex.com/category_s/75.htm

Good luck and keep us posted on what solves your issue.
 

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Fep-Pro's, tighten after every drive for the first 3-4 times, usually don't have issues after that. Tried numerous others, the only ones ok besides Fel-Pro's were the GOOD Mr. Gasket graphite looking pieces.
 

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Discussion Starter #10 (Edited)
Thanks to all for the replies. I think I will try the FelPro gaskets first, then if that does not cure the issue I will try the RemFlex. After that, gaskets with FelPro copper gasket silicone the way 64Chev recommended. I will keep posting until I get it right. Thanks again for replying....Jack
 

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Discussion Starter #12
I got a great set with my Heddman Headers made by Heddman, no issues at all. Felpros work great too.
When I ran my engine on the test stand I had no leak at all with the cheap Summit supplied gaskets (3-piece) and Purple Hornies. The problem started when I had the FlowMaster Header Back kit hooked up with the engine in the car. Thanks for the reply, Jack
 

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Discussion Starter #13
I am going through this as we speak. AFR 195 heads, JW nova 1-5/8" headers. tried the felpro 1404 gaskets had leaks on every port. A straight edge showed the flange and tubes to be pretty far out of wack. Had the header welds sanded flat on a belt sander and tried the Percy's, same deal. Pulled the Percy's out and noticed that the ports on the gasket are much taller than the ports on my heads. Percy advertises 1.5" x .1.5" but the actually measure 1.65 tall. Today I bought a new set of fel pro 1404 gaskets which match the exhaust ports perfectly and tried putting a bead of ultra copper on both sides of the gasket. I am letting it cure over night and will report back tomorrow.


Scott, how did it turn out? Jack
 

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Bottom tap the holes in the head (3/8-16) and find the longest bolts that you can use. Loosely bolt the header on without gaskets to make sure the bolts won't bottom out. Most header bolts are too short and I've seen cases (especially with thick header flanges) where you can use 1/2" longer bolts, actually doubling the amount of thread engagement. Don't overdo the anti-sieze cause there won't be much room left in the bottom of the holes with longer bolts and you don't want it packing up solid in there.
 

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Jack,
I fired the motor this afternoon and it seems like this was the cure. I only did the right side yesterday. Now that the right side has been quieted, I can hear the left side leaking so I replaced the gasket with a felpro and ultra copper tonight. I will run it again tomorrow and try to heat cycle it a few times to make sure that it is all good. Probably wont get a chance to drive the car anytime soon as the roads are heavily salted here.
 

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Discussion Starter #16
Bottom tap the holes in the head (3/8-16) and find the longest bolts that you can use. Loosely bolt the header on without gaskets to make sure the bolts won't bottom out. Most header bolts are too short and I've seen cases (especially with thick header flanges) where you can use 1/2" longer bolts, actually doubling the amount of thread engagement. Don't overdo the anti-sieze cause there won't be much room left in the bottom of the holes with longer bolts and you don't want it packing up solid in there.
Jack,
I fired the motor this afternoon and it seems like this was the cure. I only did the right side yesterday. Now that the right side has been quieted, I can hear the left side leaking so I replaced the gasket with a felpro and ultra copper tonight. I will run it again tomorrow and try to heat cycle it a few times to make sure that it is all good. Probably wont get a chance to drive the car anytime soon as the roads are heavily salted here.
Good idea Mark, I will try when the car comes back from the Dyno Guy.

Thanks Scott, looks like you just might be on the something that will work for those nasty, bad, ugly non-sealing headers. :yes: Jack
 
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