Thread Pitch on Dog House?

[dr_frankenstein]

can anybody tell me what the threads are for bolting the dog house on the 86/87 intake?

I want to say 5/16-18 but it doesnt seem right....

A.j.

 

[gunslinger]

8x1.25

 

[dr_frankenstein]

8x1.25

thank you so much!

A.j.