bolts..

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JJMclure
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bolts..

Post by JJMclure »

Regarding lower arm to chassis bolts, can I safely use grade 8.8 or would I be better going higher? I need some 1/2" bolts and found some ARP ones that have an advertised yield strength of 170,000psi which I made to be 1172 MPa, a quick search shows as being slightly higher than grade 12.9. I have only searched on the dreaded online flea market so must admit I haven't explored all avenues yet but want to get the correct ones for the job. Your advice gentlemen?


don't nibble on the barrel, pull the trigger!

stevieturbo
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Post by stevieturbo »

Pic of setup ?


10.9 or 12.9 should be readily available anyway ?

Cant imagine there ever would be any need to go to ARP for basic bolts
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

JJMclure
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Post by JJMclure »

here we go plz ignore the shoddy painting and surface rust
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do you know of any on line suppliers?
don't nibble on the barrel, pull the trigger!

stevieturbo
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Post by stevieturbo »

Almost unlimited suppliers on ebay.

Almost all cap screws, ie allen key type bolts are high tensile 10.9 or 12.9

Generally with imperial bolts though, ie 1/2" etc they use a different numbering system for high tensile.

Given size of bolt I'd have little concern about even an 8.8 though

My lower suspension arms have 4" long 1/2" bolts for the main fixing along with spacers to accommodate the rose joint and never had any issues.
Likewise the top bolt where the coilover secures to in a similar fashion.

I did not use cap screws, both of these would be a very high load application.
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

JJMclure
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Posts: 264
Joined: Mon Jul 21, 2008 9:19 am
Location: wotford 'earts

Post by JJMclure »

I did wonder about cap screws, nice one thanks for your help Stevieturbo
don't nibble on the barrel, pull the trigger!

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