LS1 Exhaust manifold bolts no more??

[White95]

I just got off the phone with my local parts dealer and he told me that GM stopped producing LS1 exhaust manifold bolts. So what do us header guys use for bolt when installing our headers!?!?!?!?!

[OneQuickV6]

Go to the parts store and get some grade 8 bolts. Take one of your bolts so you can match up the size and threads.

[White95]

I already have headers and he reason i wanted to switch to LS1 bolts was b/c of the 10mm head

[viper98885]

Get the ones for the front or rear engine covers for the LS1 or LS6. Or for the Valley pan for the Z06. That particular bolt is used all over the place on the LS1s

[OneQuickV6]

you're swapping them because you want a different head?? Seriously??

[White95]

i guess you've never seen how much room there is between the the bottom bolt and the primary on a 3.4. i'm not just swaping the bolts, i swapping heads, cam, intakes, pretty much the hole freakin top end. 10mm would just be easier to work with when reinstalling

[OneQuickV6]

I've seen it. I just don't think the head size makes a big difference. If you have the right socket set, it's not that bad either way.

[White95]

well theres no way to get a socket on the bottom bolt. Heck theres barely enough room for a small wrench

[viper98885]

The 10mm head is really MUCH easier to deal with on the 3.4s.

[viper98885]

12551187 is the old part number.

11515758 is the new GM Part number.