Hi Folks,

I have a new set of BBK shorty headers installed on my freshly built 302, and they're leaking. In hindsight, these headers were probably a mistake, but I have them now and will try to deal with them. The 3/4" long bolts that come with them are too short, a well known issue it seems, so I ordered a set of 1" long ARP header bolts. I also ordered a set of Remflex header gaskets, which were recommended by a couple different places as the cure-all for header leaks. I'll give 'em a try.

Questions are, do you install everything dry? Bolts and gaskets. I was told by one place to use high temp RTV on the header gaskets and on the ball flange, but the engine shop that built my engine says to install the gaskets dry. Same question on the bolts...dry or lubed? I don't have any of the ARP ultra-torque thread lube or whatever it is called, but I'm sure there is an equivalent product out there, no?

I'm inclined to install everything dry, but I'm certainly no expert. If there's a mechanic's trick (like using RTV) that helps matters, I'd gladly do it.

 

I install the gaskets dry, but I use soft copper gaskets. I use antisieze on the bolts. Check the fit of the flanges against the heads. I've had one set that needed the bottoms of the flanges chamfered to sit flush with the heads (Shelby Tri-Y's on E7 heads). Do those gaskets have the end holes opened to a "U" so that you can mount the header then slip the gasket behind them from the top ?

 

They don't appear to, no. These are the ones arriving tomorrow, and were recommended by a few different people. They're not expensive, and not a big deal to change, so worth a try.

https://www.summitracing.com/int/parts/rfl-3028

Good point on the flange flatness/trueness. I'm going to check them with a straight edge once I have them off again.

 

Not asking if the flanges are straight, I'm talking about how they fit against the heads at the bottom, those Tr-Y's I had interfered with the profile of the heads below the ports. The copper gaskets I've found to be the best at long term sealing, once they're tight, they stay that way for years. The bolts don't work loose because of gasket compression. They don't burn out either.I just replaced a header on my van and didn't have any new gaskets to use, so I reused two copper gaskets. No leaks from reusing them.

 

Ahh, OK, understood. I thought you meant that the edge of the header flange had a lip or something that was interfering with sitting flat. I'll take a better look once it is apart. The driver's side is nice and quiet, it's the passenger side that's leaking, and it could be at the ball flange too.

 

To check you header to head flatness you can do what I did. Glued to sheets of sand paper to a piece of very flat ply wood then start sanding. You will be amazed has how far out the headers are from true flat. Take your time and ensure your are not cocking the headers as you sand. I think I started out at 100 grit which seems extreme but after you sand the headers the paper smooths out to 220 ish….