I’ve hit the breaking point on header leaks. I’m tired of gasket after gasket failing, so I’m ready to spend more money than should be necessary to get the headers to seal.

Issue #1: Header Studs vs. Safety-Wired Bolts

I’ll be installing these headers (again) on aluminum heads, and I don’t like the idea of installing and reinstalling threaded steel fasteners into aluminum. Whatever fasteners I choose will be stainless steel from ARP.

Here are my options:

Hex Bolts 400-1101 $17.88
12 pt. Bolts 400-1201 $17.88
Hex Bolts (drilled for safety wire) 400-1103 $30.95
12 pt. Bolts (drilled for safety wire) 400-1203 $37.69
Hex Studs 400-1412 $47.95
12 pt. Studs 400-1402 $77.95

What is a better option? Use the studs without safety wiring them, or using the pre-drilled bolts and safety-wiring them all together? Ideally, I’d use the studs safety-wired together, but those nuts are too small to drill a hole through the side of one. I have enough extra room to deal with installing the headers over studs. I’ll use lock washers on both the studs or bolts this time.

Issue #2: Which Gaskets to Use?

I’ve read and it seems like the top 4 are (in no particular order):

Earl’s Pressure Master $40.39
Mr. Gasket Ultra-Seal $14.88
Percy’s Dead-soft Alum. $34.95
Fel-pro Steel-core Laminate $15.99

I haven’t used any of the aforementioned types before, other than the Mr. Gasket Ultra-Seal. But, I didn’t soak them in water as some have recommended before installation. I’ve also tried Permatex Copper silicone and it’s helped somewhat, but still hasn’t solved the problem. I’ve cut the header flanges in between the end cylinders and middle cylinders. I haven’t had the flange surfaced for flatness. Would it be worthwhile? I’d hate to grind away too much of the weld on the inside of the flange, so maybe I’d try to weld on the outside of the flange to reinforce it. The headers are the cheap Heddman variety, so the flanges aren’t very thick. Out of the above 4, what is the gasket of choice? Any other tips?

 

I used Breslin Bolts... they bolt in then there is an allen in the middle to tighten them... I also used Percy Aluminum.... I don't have a bunch of miles since the header install, but everyone else that uses those bolts has said good things about them... I didn't want to use the stage 8 stuff and have more work to do with the locking clips, clearance, etc...

Raf

 

Don't get Mr. Gasket 'ultra seal'. They don't 'ultra' do anything. They are supposedly 'blow out proof'...well you can guess what happened after about 20 miles.

I used Fel Pro's 1406, which is the steel core laminate that you listed. That works absolutely fine for me. The gasket itself is somewhat malleable and conforms to the shape of the flange, so ultimately the flange presses into the gasket and form fits it making a nice seal.

As for bolts, I just used regular bolts that came with my headers. A set of ARP stainless steels would look killer though, compared to my rusted ones.

Copper gaskets will work very nice too and will have practically zero blowout. Can't say I've heard of a case where that was the issue. Dead soft aluminum will work well too, I used that stuff on my collector flanges, and no complaints yet.



What it boils down to is that it has to be something that is not a composite material, or anything with Mr. Gasket on the label.

 

Not really sure why so many people have such problems with the gaskets and sealing the exhaust

I dont think the studs and safety wire will help if you dont know why its leaking

Retorquing the bolts with the heat cycles
Getting a quality gasket and adding some high temp sealant on it for extra little bit
Making sure the flange and head surfaces are even and flat - welding spatter and irregularities
If you have an excess of heat buildup in your exhaust then youll get some flexing along the flange which kills alot of gaskets for hotter engines - fix this by cutting out the useless part of the flange in between the primaries

Still leaking you need to check how much stress your exhaust is in and if something is knockin it

 

If your header bolts are backing out, then safety wire will keep them in. Stage 8 locking bolts will also work. I don't like the Breslins because they have a 12 point head, which is nearly impossible to get a box wrench onto with most headers.

 

One way to stop gasket blowout is to cut the headers right on the plate that is welded to the primary's.

 

Forgot that one, very important.

Also, torque from inside out.

 

I know of a few cars here locally including myself that use Earl's header gaskets. They have worked quite well for us. I have had a bolt fall out and the gasket still seals. By the way I'm also using the Breslin header bolts in the tough to get areas. Excellant results.

 

Use dead soft aluminium gaskets and re-torque after heat cycle.

 

You touched on one of the problems....cheap headers with thin flanges. I would check them for flatness before you destroy another set of gaskets.

 

The breslin or stage 8's would be the best. Just a bit more than those $30 drilled for safety wire bolts, and I imagine they're nicer to use.
I drilled some allen bolts for safety wire on my engine. After trying to safety wire them up with the engine in the car, I realized this would be the biggest PITA i've ever experienced and gave up. I just retorqued them after a few heat cycles and they're fine. The collector bolts (one of them) however backed out.. I think I just didn't tighten that one enough.

I like copper gaskets, FWIW.

 

Were you using a wire twister?

 

I put my hooker headers on with Percy's Deadsoft aluminum and Breslin locking bolts, so they get my vote...very happy with the results.

 

FEL-PRO's have served me well, even after several years of abuse at the track. You should periodically retighten them anyway.
Thanks

 

Sure was using a wire twister. But getting my hands and the tool in there for the back ones was a nightmare. Then finish twisting it around and locking it in place by hand was impossible. If the engine was on a stand I could (and would) have done it.
Or might have been possible if I used the thin .023" wire or whatever that stuff is. I couldn't find the "normal" racing stuff, I had an autoparts store order some in for me, it was more like bailing wire, .035" or so. A lot thicker than I would have wanted.