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I have AFR 195 heads, Felpro 1405 and 1 5/8" headers (Flowtech), I also have a few small leaks between the heads and the gasket. (that is not good when I have EFI:- )
What is the best way to stop the leaks?
ARP universal header studs. The felpro blue steel impregnated gaskets are the best and reusable. I've installed some motors that had warped or thin flanges on the primaries. So I coated the pipe side of the gasket with Permatex Red high temp sealant.
ARP universal header studs. The felpro blue steel impregnated gaskets are the best and reusable. I've installed some motors that had warped or thin flanges on the primaries. So I coated the pipe side of the gasket with Permatex Red high temp sealant.
I use 2 sets of the Blue Felpro gaskets on 2 different sets of headers (one set was warped badly) and they completely sealed the leaks for years now. Take 2 gaskets per side and red permatex them together with clamps to cure them and you are good to go once they set....This method was superior for me versus any other exotic gaskets like Percy's, aluminum gaskets, copper, etc.............Standard header bolts were used as well. Nothing fancy just all of these header gaskets are too thin to bridge any gaps that form from heat over time. I also have AFR heads.
Here is an old hot rodders trick when headers refuse to snug up tight. Remove the header. Using a hacksaw cut a "kerf" between # 1 cyl and # 3. And also between # 5 & # 7 cyl on the back side of the flange. If you don't know what a kerf is, its a notch the thickness of the blade, but not all the way through the material. Your kerf only needs to be an 1/8" deep in the flange or less. DO NOT CUT ALL THE WAY THROUGH.
This"'kerf" will relieve some of the warping and allow the flange the snug up closer to the head. Because the "kerf" is on the back side of the flange, it will not be noticeable. Now do the other header, same pattern.
Always install the header bolts with the outer bolts first, then torque from the center bolts outward. No header should ever require two gaskets and a bunch of goop. If so, the flange should have been die- grind flatter.
Percys gaskets are top of the line. Each gasket is 8 layers thick aluminum. Four layers conform to the head ports, four layers conform to the header flange. When I open the Percys package, I thought they accidently sent 16 gaskets. But its 8 layers for each bank. There is a reason some header gaskets are <$20 and some are $40. Quality.
ive had good luck,using the ''fiber'' gaskets,go get a wall-paper trough,full it 1/2 full of the hottest water[tap],put the gaskets in over-night,the next morning,take out 1 gasket and install,then do the same for #2 gasket,run engine to temp,then let cool and re-tighten
use Red Devil red high temp silicon on the flange, not thick, just a light coating, we use the stuff up around 2100* at the factory im at and it still seals good, works great on all my headers
Like Stocker says tho, you need to retorque three times before they generally stop backing out, heat them up, let em cool off, then tighten, do that three times and your good to go for a year or so and check again. usually only takes those three times though.
Copper or aluminum(my choice) gaskets and ARP bolts, studs always interfere.
Flanges should have been checked for flatness before being installed and filed to make sure flat.
I used a large mill cut file [long enough to cover all four ports] and mill file the flange until 1 cut covered the entire surface evenly. Haven't had a gasket leak since then. T
I always re-torque the header bolts after each outing (after it's cooled off) until the bolts are staying tight. never any leaks for me
I use a similar strategy, along with stage 8 bolt assembly on mine. Haven’t had a leak yet in 9 years with my side pipe headers.
on a side note, why 1 5/8” primaries with AFR 195 heads? With the flow those things got the primaries gotta be restricting flow above 4000 tp 4500 rpm.
No gasket. Direct fit from header to the head, with Permatex Red high temp sealant. Header and head need to be reasonably flat. The gasket is the weakest part of the connection. Used this method on a small block in my 74 for 23 years with no loose bolts or leaks. Try it, you'll like it.
Ed
Earls header gaskets and I safety wire my bolts. My bolts never back out and I never have leaks.
I like these^^^^^^^^^^^if I decide to abandon the double Blue Felpro gaskets method I use which have not failed me yet in over 10 years of 3 different header sets..............
I use a similar strategy, along with stage 8 bolt assembly on mine. Haven’t had a leak yet in 9 years with my side pipe headers.
on a side note, why 1 5/8” primaries with AFR 195 heads? With the flow those things got the primaries gotta be restricting flow above 4000 tp 4500 rpm.
Almost everything has a reason :- )
In this matter, my reason is time :- )
I do have a set of Hooker 1 3/4" headers in stock, so I will come to that, in the (maybe near) future :- )
Almost everything has a reason :- )
In this matter, my reason is time :- )
I do have a set of Hooker 1 3/4" headers in stock, so I will come to that, in the (maybe near) future :- )
1 3/4 sounds more like it.
that gasket in in the pic is the same one I’ve used for last 9 years with no failures. I did have to port out the holes a bit to fit my side pipe primaries.
Exhaust leak, from the heads to headers
