Xenodrgn

Topic. ^^^ And how long are the 2.8 manifold bolts?

Mark A Shields

I'm not sure about Grade 8, but if I remember correctly stock bolts to the heads for headers or what not are prone to break. Grade 8 bolts are extra strong. Think of the pain in the butt of have a bolt break off in a head.

Apeiron

Nevermind

SpeedCat86

'Grade 8' refers to the strength of the bolt. Grade 8's are about the strongest you are going to be able to find. The other most common types are grade 3 and grade 5.
What you really need to know is that the grades represent different shear strenghs of the bolt.

Grade 3: The stuff you get at the Home Depot. about 3000 psi

Grade 5: You can usually get these at a good auto parts place. 7000 psi

Grade 8: Gotta go to an industrial supply place for these. 10K psi


I can't find my McMaster catalog right now, so the ratings may be off. Will endevour to find out.

Xenodrgn

Thanks!

SpeedCat86

Found out that yo can get grade 5, grade 8 and stainless bolts in SAE and Metric at Lowe's. Who knew?

JPrevost

SAE 0-1-2 74,000psi Low carbon Steel
SAE 3 100,000 Med. Carbon Steel
SAE 5 120,000 Med. Carbon Heat T. Steel
SAE 6 133,000 Med. Carbon Temp. Steel
SAE 7 133,000 Med. Carbon Alloy Steel
SAE 8 150,000 Med. Carbon Alloy Steel
better than grade 8:
Supertanium, 160,000 Quenched Temp. special Alloy Steel
A354BD;A490 150,000 Med. Carbon Quenched Temp. Steel
N.A.S. 144, MS2000 160,000 High Carbon Quenched Temp. Alloy
N.A.S. 623 180,000 High Carbon Quenched Temp. Alloy
Aircraft asigned steel 220,000 High Carbon Quenched Temp. Alloy

Thanks to my Pocket Ref by Thomas J. Glover
Isn't that so the mechanical engineer side of me