Patriot header leaks? Anyone had this

[smh00n 75]

I have a set of Patriot H8420 headers fitted to Dart Pro 1 alloy heads on a 302, and after about 100 or so miles, it looks like the last port on the drivers side is leaking. It literally just started one day - first few runs on the motor was great then it started chuffing.

I've done everything humanely possible to fix it, including milling the mount faces flat.

Has any one had any issues with this head and header combo? It's doing my head in.

I have screwed these things up so tight it's scary. And I am using multi-layer exhaust gaskets, including also putting a second standard one on hoping the extra thickness would cure it. Have cut the flanges, tightened them, even cussed them. Nuthin works.

The passenger side is perfect, the front of the drivers side is perfect.

[Rsanter 149]

The copper gaskets are the best you can get

[Mach1 Driver 528]

A few months ago RPM talked about cutting the flange on his headers to allow the tubes to flex individually. I realize I'm showing the passenger side, and you wouldn't cut the gasket too, just the flange, but you get the idea. That last tube isn't going to bend on these shorties with the collector right there so you may need to free up the others to get some wiggle room when they get hot. Hopefully Bob will show the picture of his fix and discuss the results (it was probably done to a different brand of headers though). I suspect that cutting the flange would be your last resort and an expensive experiment, but if nothing else works....its the old problem of the unintended consequences of aftermarket designs and parts.

[RPM 1,157]

My AFR 185 heads don't have much sealing area around the ports and between the bolts. After blowing out a couple of gaskets I cut vertical reliefs in the flange. No problems since with the  then cheap Hedmans. 

Cutting the flanges was nothing compared to rerouting the tubes.

 

 

[Mach1 Driver 528]

Impressive!

[smh00n 75]

I have cut the flange and it made a slight difference.

But, it is still there.

My last resort is to try copper gaskets.

[Mach1 Driver 528]

I have read that Remflex graphite header gaskets may help.

[smh00n 75]

I can't get SCE copper gaskets here, and the only Remflex are the smaller ones that need to be cut to match the ports on the heads.

I'll try 2 standard gaskets I have here in the next few days and see how they go.

I'm sort of resigned to buying new headers, which if I so will be FPA ones which will cost me a lot. Nothing else seems to fit with a Borgeson box and not hit or hang. Like someone else put on a review, these things have been around for 50 years, surely someone has made a set of headers that fit.

 

[smh00n 75]

Well I got a reply back from Patriot who tell me these headers are not designed to fit Dart heads. Summit don't say they will or won't :(

Anyway, Stan at FPA has really stepped up and is building me a set to pick up when I go to the Bristol NASCAR night race next month. It's only a $2,000 cost, what else would I do with the cash.

[Rsanter 149]

On 8/5/2023 at 3:35 PM, smh00n said:

Well I got a reply back from Patriot who tell me these headers are not designed to fit Dart heads. Summit don't say they will or won't :(

Anyway, Stan at FPA has really stepped up and is building me a set to pick up when I go to the Bristol NASCAR night race next month. It's only a $2,000 cost, what else would I do with the cash.

They bolt on or they don’t. 

I would want to know why they won’t work if they bolt on

[smh00n 75]

They bolt on fine, but the driver side leaks. I think the ports are too big for the headers, and its squeezing out the bottom of one pipe. I have tried *everything* to stop it. Funny, it only leaks on pone port on one side. The heads have been mildly ported so maybe the man got a bit keen on one port?

Anyway, Stan has built and sent a new set for me. I pick them up September 14 when I go to Bristol for the NASCAR race. Cannot wait, even though they cost me $2,000 local currency.