Uprated head bolts

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Turbo-Brown
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Post Tue Sep 25, 2007 6:47 pm

Haven't got one handy to measure, but can anyone tell me if I need M10x160mm Grade 12.9 Socket Head Cap Screws?

Cheers!

Alex
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BristolBulldog
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Post Tue Sep 25, 2007 7:25 pm

no idea to your direct question, but ARP typically do the best head bolt and stud conversion kits known to man.
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exup
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Post Tue Sep 25, 2007 8:34 pm

AGREED ARP are v good
wheres the best place to get them
e30_Turbo
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Post Tue Sep 25, 2007 8:42 pm

Alex,

150mm x M10 mate :cool: Stock are 8.8 or 10.8, some even had 12.9's ( found a set in a eta lump ).

160mm x M10 can only be used with a decomp plate, unless you get down with a drill and tap them deeper, knowing you it's not out of the question :mad:

ARP are the best but you pay for it, saying that I have ARP in my new engine :cool: but never had any probs with the 12.9 bolts I have or have supplied to many on the zone.

If you get stuck Alex let me know and I'll bung a set in the post, I still owe you for the solonoid IIRC :D

Mark
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Post Tue Sep 25, 2007 8:46 pm

exup wrote:AGREED ARP are v good
wheres the best place to get them
Try VAC motorsport in the US, they do them, or I can sort you a set of 12.9's out Frank, no worries.

OT, I tripped over my old 325i afm in the garage and thought of you for some reason? Where you in need of one?

Thanks, Mark.
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BristolBulldog
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Post Tue Sep 25, 2007 9:08 pm

i got mine from vac as well. They must be in demand as i sold them UK ebay for about a £5 loss!
Turbo-Brown
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Post Tue Sep 25, 2007 9:25 pm

Ooh, didn't know ARP did a stud conversion....now that is interesting!

Seems that 12.9 soc heads are relatively cheap for set though so they're quite tempting.
Last edited by Turbo-Brown on Wed Sep 26, 2007 6:57 am, edited 1 time in total.
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BristolBulldog
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Post Tue Sep 25, 2007 9:29 pm

Yep, mine was a stud conversion. Amazing quality, and you can re-use them zillions of times.
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Post Tue Sep 25, 2007 9:50 pm

BristolBulldog wrote:you can re-use them zillions of times.
:lol: Hopefully won't be getting through that many head gaskets!
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Simon13
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Post Tue Sep 25, 2007 10:22 pm

i've got a set of the early non stretch 12.9 bolts. With the 6 sided heads. Ant wanted them, but i keep forgetting to give them to him
isTURBO
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Post Sat Sep 29, 2007 2:44 am

Hi Guys

Whats the difference between these head bolts and the standard ones. :?:
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Onz
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Post Sat Sep 29, 2007 3:12 am

fuel economy and performance increase. due to a better seal between the head and the block. but you should really change the headgasket aswell :)
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chu346
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Post Sat Sep 29, 2007 9:03 am

isTURBO wrote:Hi Guys

Whats the difference between these head bolts and the standard ones. :?:
They don't stretch. If you boost an engine with normal stretch bolts the boost in the cylinders will cause them stretch. It'll be like head gasket failure.

Plus you can reuse them many times, unlike stretch bolts.



slyder have you been :rasta:
isTURBO
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Post Sat Sep 29, 2007 5:31 pm

Ahhh... :twisted:

Cheers Guys :cool:
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