What are header bolt size, specs, thread, lenght etc.

[V6UnderPressure]

anyone know the measurements.

scott

 

[87gn-newbee]

ARP has some studs part # 120-1402 I just ordered some.
Dan

 

[V6UnderPressure]

Thanks but I dont want part numbers, I want actual specs.

Scott

 

[tom h]

http://perfauto.tripod.com/data/0-046.pdf

You'll find the bolt sizes called out under items # 54, 55, 56.

My 87 GN doesn't actually use any bolts (#55), it only uses 2 lengths of studs (54, 56).

Strictly, studs are only needed near the front of the D/S, where brackets for accessories are mounted on the studs, but GM used the studs on all positions.

 

[87gn-newbee]

Tom do you know the intake bolt size? I could not see it.

Dan

 

[tom h]

Originally posted by 87gn-newbee
Tom do you know the intake bolt size? I could not see it.
Dan

sorry, offhand I don't know.

 

[V6UnderPressure]

Originally posted by tom h
http://perfauto.tripod.com/data/0-046.pdf

You'll find the bolt sizes called out under items # 54, 55, 56.

My 87 GN doesn't actually use any bolts (#55), it only uses 2 lengths of studs (54, 56).

Strictly, studs are only needed near the front of the D/S, where brackets for accessories are mounted on the studs, but GM used the studs on all positions.

Never Fails, I dont have adobe as my old one didnt work. Can anyone "Type" it for me here???

 

[6pack]

Here ya go

54. Stud, Hex(M8x1.25x20/3/8"-16x47.5 LW)
55. Bolt, W/LK WA(3/8"-16x25.5)
56. Stud, Hex W/SPL LK WA (3/8"-16x.92")

 

[tom h]

Re: Here ya go

Originally posted by 6pack
54. Stud, Hex M8x1.25x20 / 3/8"-16 x 47.5 LW
55. Bolt, W/LK WA 3/8"-16 x 25.5
56. Stud, Hex W/SPL LK WA 3/8"-16 x .92"

Although GM doesn't describe it, even stud # 56 has METRIC end on one end, M8 x 1.25 x 20 .

The only difference between # 54 & 56 is the length of the 3/8-16 english threads that attach to the cyl head.

#55 was not used, at all, on my '87.

It is maddening how GM combines english and metric on the same car, and sometimes even combines it on the same fastener !

 

[DR BOOST]

3/8 - 16


i dont even understand what the heck was written up there^

dont forget that you have atr headers