Damn header leaks! wtd?

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V8-valiant

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what have YOU tried for header gaskets? got my headers on spent the big bucks on copper gaskets thinking i wasnt gonna have to screw with it and they leak, BAD! whats the trick guys!?! whats your setup? tips? thanks alot!
 
I have always used the blue felpro gaskets but I use exhaust sealer from napa,the stuff is tar like but gos on like rtv and it works.I learned about from my brother who used to work at a exhaust shop and its only at napa (says napa on it),its in a white tube that looks like silicone,I swear by it.
 
I`ve heard that copper is the way to go, but I`ve also heard you have to buy the thick ones.......something like .040.????
 
There is a company called remflex that makes a very thick header gasket i see them at the local carquest when i go in there, i should mention that my local carquest is a special one that deals with race parts as well as replacement auto parts so they deal with some very neat stuff. Well anyway back to my point the sprint car racers around here swear by them but again they are very thick at least as thick as five header gaskets put together each and they look to be made out of a similar material as newer cars head gaskets those that are made to make up for slight variations in the deck of the block and head. Anyway i havent used any yet but again the sprint car guys love them and as they are spending 50k plus just on their engines i would think they are only about quality. I plan on trying a set on my car when i install headers my only worry is they will be to thick and put the header to far out there but i wont know till i try. May want to try them if you cant get it to stop leaking. Good Luck Justin
 
Locking header bolts. Stage 8. They require a little trimming, but once tight, they mechanically cannot back off.
 
MR Gasket ultra seal are the only stuff i use, you can even reuse them a few times if everything is ok
 
I use MR GASKET if availiable or felpro gaskets,I put a thin coat of red High Temp silicone on them and put 2 gaskets together! Then put a thin layer of the red high temp silicone on the side facing the header only! NOT ON THE HEAD SIDE! bolt them on using a good set of locking bolts,wait about an hour before you crank up th ecar to let the silicone dry real good and you should be OK TO GO WITH NO LEAKS! Remember "THIN COAT" of red High Temp silicone so it does not oooze out all over the place when tightening up.If you do get an ooze out you can trim it with a razor blade after it has dried well! Or you can buy the REALLY GOOD EXPENSIVE GASKETS! I have no use for the copper,and a lot of the other brand of aluminum ones that compress that cost $30.00 and up a set! Just havent had no luck with them! A lot of times the problem is the flange of the header is warped,this happens a lot with thin flanged headers when they are over tightened!
 
I have always used Mr. Gasket or Fel-pro with Permatex copper sealer. No problems with my 11.5 to 1 compression 383. Worst case scenario - you can have someone run a weld bead around each port and grind them flat around 1/16" to 1/8" higher than the flange. I know some guys who have done this on engines with crazy compression that were always blowing header gaskets. The beads have to be ground to the exact same height for it to work well.
 
you NEVER said which headers youn are using i have a set of doug thorly try Y (with3/8 flanges) my gaskets are HIGH TEMP RED SILICONE ONLY put it on header bolt up with locking bolts let dry for a couple hrs b4 firing and ive NEVER had a blowout if that dont work for you use Mr gaskets with a good coating of "copper coat"" that worked on my /6 with a 6into one direct connection header good luck
 
you NEVER said which headers youn are using

Yes what header brand are you using??..i'm running tti's and with the 3/8" flanges there's less chance of leaks,i use the fel-pro gaskets with no leaks ever to speak of,the cheaper headers have thinner flanges which over time can warp and distort..
 
There is a company called remflex that makes a very thick header gasket i see them at the local carquest when i go in there, i should mention that my local carquest is a special one that deals with race parts as well as replacement auto parts so they deal with some very neat stuff. Well anyway back to my point the sprint car racers around here swear by them but again they are very thick at least as thick as five header gaskets put together each and they look to be made out of a similar material as newer cars head gaskets those that are made to make up for slight variations in the deck of the block and head. Anyway i havent used any yet but again the sprint car guys love them and as they are spending 50k plus just on their engines i would think they are only about quality. I plan on trying a set on my car when i install headers my only worry is they will be to thick and put the header to far out there but i wont know till i try. May want to try them if you cant get it to stop leaking. Good Luck Justin

Remflex is the only gasket that would seal my TTI's. I tried them all. You don't have to retorque the bolts again. This is the only gasket I'll use.

Fred B
 
sorry guys im running the spitfire's. couldnt afford the tti's and it sounds like a headache with fit and installation, oh well. i dont think its the flanges they have like 7/8 header flanges i've been messing around with some other gaskets its getting better! thanks again everyone for the help!!
 
what have YOU tried for header gaskets? got my headers on spent the big bucks on copper gaskets thinking i wasnt gonna have to screw with it and they leak, BAD! whats the trick guys!?! whats your setup? tips? thanks alot!

I had the same problem and tried amost everything. One day I stopped at the local performance shop and there was an old guy there who listened to my header leak problem. He knew old mopars and right away knew what I was doing wrong. He said that 3 out of six bolts (oh yeah 2 are studs in water jackets) are really had to get at on drivers side. What the problem was is that I was over tightening the easy to get at bolts and then tightening the hard to get at bolts as tight as I could. That caused uneven gasket seal. He told me to change the gasket and snug up the easy to get at bolts then tighten the hard to reach ones as tight as I can. Then go back to the easy bolts and re snug them a bit. When I fired the engine it was the first time since I owned it that there was no header leak.
 
Well believe it or not. The best luck I've had is with the stock type gaskes u get for exhaust manifolds. they have the perforated metal on 1 side and paper like material on the other. I put a lite coat of either red or copper rtv on both sides and let it set up about 1/2 hr before installing. I put the metal side out tward the header. I have no leaks and I'm useing 28 year old "blackjack" 89.00 headers on a small block. I learned this trick working on my dirt stock cars. I have even reused the gaskets with a new coat of rtv.
 
the spitfires use a 5/16 flange Harold said hes got a 'new
'
'
'supplier of gaskets maybe give him a call back if ya cant them to seal
'
'
 
I double up Fel-Pro header gaskets and use the high temp copper RTV. After 20k miles I am just beginning to have a little leak.

When I first put in the 360 I used the gaskets that came with the headers (Hedman) and they leaked like a sieve. I tried the manifold gaskets that came with the rebuild gasket set and they were worse, the gasket is open between the two center ports and gives a straight shot leak path. I got a set of Mr. Gasket Ultra Seals, they were better but still leaked. Tried copper gaskets but the raised bead does not line up with the raised surface on the header flange and they leaked. Had always had good luck with Fel-Pro and decided to order them and also decided to double them up. It was also recomended to me to use a sealant. That worked and has been good since 05 when I put them in.
 
I don't know why I didn't mention this in my first post but I cut the gaskets into three pieces. One for the front port, one for the middle two, and one for the rear, and throw away the useless parts in between that just discolor and warp. I use just enough of the copper RTV to stick the gasket sections to the heads directly centered around the ports. When that has dried enough that they will not move I put a thin coat on the header side of the gasket sections and let that dry completely. Then I bolt the headers on and retighten after a few hours of use and again a week or so later.
 
i second the remflex. they are thick and take up any inconsistancies in the header flange. no sealer needed.
 
I've always used Felpro with good results. As was already stated, make sure that you tighten down evenly.
One thing that I have found that was VERY important IMHO, was to fire up the motor and let it warm a little, shut it down and then re-tighten the header bolts. It is amazing how loose they become once they reach operating temp. By doing this re-tighten when hot method, I have yet to one leak.
 
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