1974 C20 Soon to become a project...

[Super_Dave]

Today, #2 and I had to fix an exhaust leak at the header flange. I had ordered a set of Remflex gaskets, (anyone wanting trouble free gaskets for all performance levels... REMFLEX!). Pulled the bolts from the Heddman Ceramic Hedders and popped off the new gaskets that came with the headers. Take my advice: DO NOT USE THE GASKETS THAT HEDMAN SHIPS WITH THEIR HEADERS! And while we are at it: DO NOT USE THE HEADER BOLTS THAT COME FROM HEDMAN! THEY WILL RUST AND CORRODE IN A MATTER OF DAYS!!

Rant over. Looking at both Header gaskets showed multiple blowouts. In fact, the two center exhaust ports had a blowout 2" wide across the top and extending all the way down to the bottom of the ports. Not bad for 1,200 miles, huh?!

Talked to ARP and they recommended 3/4" header bolts... with the Hedman .25" flange and the .125" Remflex Gaskets and the .0625" star washers, it's not going to work. Go with the 1" bolts. My 3/4" are on the way back for replacement with 1".

Remflex says to crush the gaskets 50% when tightening the header bolts. The graphite based gasket material is pliable and will expand back out against the heads and headers. We did as advised and cranked BABA YAGA! up... Music to my ears! Runs a lot quieter under normal throttle, so all the leaks were adding to the noise factor. With multiple leaks, it was difficult to tell how much noise they were responsible for until the crappy Headman gaskets were replaced..

According to Remflex, you don't need to go back and re-torque the header bolts. Since I have to replace the crappy Headman bolts with 1" ARPs', it will be interesting to see if they backed off at all.

NICE BLOWOUT... HUH! Looked like this all over the both gaskets. I have serious questions about using anything from HEDMAN again.