Exhaust Mani bolts

TheReelMuhcoy · Aug 5, 2014

Anyone ever use other than factory bolts for the exhaust manifold? I was thinking of getting some grade 8 stainless bolts. I also just found BPD's titanium bolts. Thoughts?

MrOneEyedBoh · Aug 6, 2014

I'm getting work done to my truck. When they have the manifolds off, I'm getting them to replace them with ARP flange head bolts in SS. Some say its overkill, but USA made fasteners are far superior to import fasteners. The thread is m8x1.25x50mm. I also bought m8 flat washers.

While you have them off, coat them in a copper anti-seize and torque to 24 ft#. Also, I'd go 6pt vs 12pt, just so you get a bit more bite on each flat of the bolt head.

Buy from Allen's Fasteners, as they allow you to buy per bolt and washer. ARP usually sells them in packages of 5 I believe, so buying solo allows you to get the 16 you need, and not have any extra.

strokin6L · Aug 6, 2014

I used polished stainless ARP's on my BD manifolds.

Navigator · Aug 6, 2014

strokin6L said:
I used polished stainless ARP's on my BD manifolds.

How do you like the BD manifolds? Any difference in EGT's?

Meniacal_Mark · Aug 6, 2014

Bulletproof makes titanium exhaust manifold bolts

strokin6L · Aug 7, 2014

Navigator said:
How do you like the BD manifolds? Any difference in EGT's?

Manifolds are nice...I had them ceramic coated. The truck barks a lot louder from about 40% throttle on up. I also changed turbo at same time...so hard to tell. Right now I have a worn out converter...and trucks seems to lug a lot more and be less responsive because of it.

Navigator · Aug 7, 2014

strokin6L said:
I used polished stainless ARP's on my BD manifolds.

Do you have a part number? Were they longer than the factory bolts?

Navigator · Aug 7, 2014

I think these are 5mm longer than the factory bolts?

MrOneEyedBoh · Aug 7, 2014

Yeah but 5mm lol that's like 3/16". Run a washer and you're damn close to OEM length. Plus the bolt doesn't bottom out in the hole, thus giving you a bit more depth to play with

MrOneEyedBoh · Aug 7, 2014

edited: I see that I ordered the wrong ones.. tHe bolts are 48mm OAL and UHL ( under head length ) is 40mm. The ARPs are measured UHL, so I just bought some 40mm ones. They 50mm will work, but with a thicker washer.