Thread: Do I use lock washers when I bolt on my flexplate?

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Hi Everyone! Should I use lock washers when I bolt my flexplate on? I'm using grade 8 bolts {the hub on the crank is tapped for 1/2 x 20 threads per inch} & I bought grade 8 lock washers. I'm going to use the Red Lock Tight. But can/should I use the lock washers/???? or does it matter??? Thanks Bill

no i use just red lock tight even you have grade 8 lock washers i would just use the red lock no worrys about the washer busting and failing on a moving part i do not use them on fly wheels would rather use a SAE or a AN washer with red lock tight

i would think it is his hemi /400 trans ?? a star washer is better then a spilt washer you do not need any washers with arp

.....yes it's for a 392 Hemi that's hooked to a turbo 400 trans. Actually the bolts that came with the transmission adapter/flexplate are 7/16" but the flange on the crankshaft was tapped to 1/2" x 20. So I drilled the flexplate & aluminum spacer hub out to 1/2" {actually 33/64"}. I didn't even think of using ARP bolts! I just went out & bought grade 8 ones. I'll check on the ARP & I will look at the 7/16" bolts that Hot Heads sent to see if they have star washers! {I'm thinking I saw some in the box!}. Didn't even think of that! Thanks Pat & Denny! Bill

GM,s came from the factory with those star washers on them.......

.....Thanks Poncho62! .... Actually ARP is right by my house so I went & got some of their bolts. Because of the Hot Heads Hemi adapter the stock Hemi Flexplate bolts were to short {they are 1/2" long} so I went with the Hemi Flywheel bolts that were 1/2" x 20 x .875 long. They don't use washers on them. So I used these bolts & the Red Lock Tight.... Thanks again! Bill

Hi Bill,
I saw you asking about flywheel torque in a post befoire. without knowing the bolt size it is improper to spec the bolt torque. The 55-60 is for a 7/16" bolt. The 1/2" should be 75-85 ft lbs.
I believe the 914 MR G does include the lock washers and providing the bolts have clearance for the clutch disc I would use them.
Mike Forte

i think he is all set on this. he may of ended up with longer bolts for the spacer ? see if he pop s in