Flex plate bolt ?
10-26-2014, 10:12 PM
#1
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Flex plate bolt ? I have a aluminum flex plate and have a set of arp bolts that are .880 long and when put though the plate they stick out just over 1/2" or .520 is that enough thread engagement? I know the rule is 1.5 x the bolt width which is around .649 so we are talking .130 light.
10-27-2014, 11:41 PM
#3
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Are you talking about the flexplate to crank bolts or the flexplate to converter bolts?
On the flexplate to crank bolts I would definitely use ARP, but longer as IIRC the crank threads are quite deep. The flexplate to converter bolts have much less shear force on them (much larger diameter circle) and .520 is probably plenty. You should check how far the threads will even turn into the converter before they bottom out, it might not be much more than that.
I'm no expert on this exact subject, but you said "anyone".
Perhaps Chris or Brian from Circle D will give you a more definitive answer.
On the flexplate to crank bolts I would definitely use ARP, but longer as IIRC the crank threads are quite deep. The flexplate to converter bolts have much less shear force on them (much larger diameter circle) and .520 is probably plenty. You should check how far the threads will even turn into the converter before they bottom out, it might not be much more than that.
I'm no expert on this exact subject, but you said "anyone".
Perhaps Chris or Brian from Circle D will give you a more definitive answer.
10-28-2014, 07:12 AM
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I'm talking flexplate to crank bolts and i have ARP bolts problem is they dont make any longer except Circle D's version which are $60 double the cost of the other bolts which i think is to high.
10-28-2014, 09:04 PM
#7
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According to my ARP catalog those are M11x1.5 thread and .880 long as you mentioned. I looked through the ARP "bulk" listings and they have nothing for M11. In other words, M11 is an unusual thread size.
I also installed a thick aluminum flexplate, but don't remember what bolts I used, probably the GM stock ones which seemed long enough.
I also installed a thick aluminum flexplate, but don't remember what bolts I used, probably the GM stock ones which seemed long enough.
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10-28-2014, 10:43 PM
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Yes they are not a common size at all I did find a Arp set fot a LS flywheel which are 244-2902 I asked about the specs and was told they are 1.075 UTH length but they have a shoulder which is .460 so they would bottom out before they got tight.
10-30-2014, 07:56 AM
#9
Factory thread engagement for the crank bolts is about .800 with the stock bolt and stock flex plate. The aluminum flex plate we sell is about .400 thick in the crank bolt area, but i'm not sure this is the one you have. We had ARP custom make bolts for this specific application They are not threaded where it would contact the flex plate so as not to chew up the aluminum, and they are long enough for proper thread engagement.
-Brian
-Brian
10-30-2014, 07:30 PM
#10
My TCI 2800 convertor(no longer in vehicle) came with M11mmx1.50 bolts. Don't know how long they are/were. You might want to check with TCI on what they have in the M11x1.50 realm.
Measured them,full thread under head,29/32"(.910") long.
Measured them,full thread under head,29/32"(.910") long.
Last edited by FirstYrLS1Z; 10-30-2014 at 07:53 PM.
10-30-2014, 10:02 PM
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I have a reactor plate and as I said I know you guys have longer bolts but like I also said they are twice the cost of the .880 long arp bolts which I think is to high.
10-31-2014, 08:10 AM
#12
Chris
