Bolts for High Flow cats/test pipes
 

I could probably make a reasonable guess as to the size bolt needed to connect a HFC/TP to the stock headers, but does anyone know for sure what is needed?

Looking at doing an install for someone and the second-hand HFC's didn't come with hardware.

Thx!

Test pipe hardware
 

What I use:

1) ARP SS bolt = 3/8-24, 1.5" length, 7/16" hex socket, (725-1500)
2) ARP SS washer = 7/16" ID, 13/16" OD, 1/8" thick (400-8509)
3) ARP SS nut = 3/8-24, 7/16" 12pt socket, (400-8302)
4) Vibrant performance custom 3-bolt gaskets = 2.5"
Torque to ~40 foot lbs on the bolt/nut w/anti-seize.

I only need four total, since the exhaust manifolds retain a stud. I just use the OEM nut (20602-41G0A) on that.

^^awesome

lol thanks, good to have this info on the forum for posterity.

I just got 3/8ths flange bolts and nuts from local hardware stores (took a lot of driving around). ARP is probably more than a little overkill haha.