SBC Flex Plates
Thread Starter
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
SBC Flex Plates
I annihilated my stock flexplate trying to get it off my block last night (4 1/4' lever and lots of bad words); it's now severely warped, but I wanted to replace it anyway as I want to keep my toes and don't trust the 40 year old flex plate with +400 hp.
I have a few flexplate questions:
Adam
I have a few flexplate questions:
- What's the standard torque converter bolt circle diameter for a 700r4 / 4L60e torque converter? 10.75" or 11.75"? (I see some that say "dual bolt pattern (LS 11.1" and SBC 10.75")...?!?!?!)
- Does "dual bolt pattern" simply mean that it supports both a 10.75" or an 11.75" torque converter bolt pattern or something else?
- 168tooth is the stock # of teeth on our cars, right? (90% certain)
- What's the best coating for long-term durability? (I see the TCI flex plate that appears to be painted black and the B&M flex plate that is kinda shiny gold and coated in... something...)
- SFI 29.1 vs 29.2 -I can see the huge jump in price when moving to an SFI 29.2 cert; at what power / RPM level should someone move from a 29.1 to a 29.2 certed SFI flex plate?
- Aluminum flexplates: Pretty pointless, right? Flexplates are already pretty lightweight and I can't see this really mattering much; a smaller diameter TC seems like it would make a MUCH bigger difference in reciprocating weight, right?
- Torque converter bolts: are they at all important? -I see 12 point ARP bolts being recommended but I can't see why it would matter.
Adam
Last edited by NewbVetteGuy; Oct 2, 2018 at 02:12 PM.
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
No need to fret. There are plenty of flex plates available. SFI plates are used for people who race.
I bought a flex plate from one of the chain auto stores. As for tc bolts if you still have the ones from the tc you can reuse them unless you just want new ones. 168 tooth flex plate is correct.
As for installation make sure there are no burrs on the end of the crankshaft or flexplate hole(s). Place flexplate on the end of crankshaft with the engine on the hoist, use lock tite blue ( or red if you want extra insurance) on those bolts
and torque to spec.
I bought a flex plate from one of the chain auto stores. As for tc bolts if you still have the ones from the tc you can reuse them unless you just want new ones. 168 tooth flex plate is correct.
As for installation make sure there are no burrs on the end of the crankshaft or flexplate hole(s). Place flexplate on the end of crankshaft with the engine on the hoist, use lock tite blue ( or red if you want extra insurance) on those bolts
and torque to spec.
Last edited by Oldguard 7; Oct 2, 2018 at 05:14 PM.
Safety Car
Joined: Dec 2012
Posts: 3,816
Likes: 1,727
From: Summerville SC
Make sure you have the Flex Plate mounted correctly. There is a front and back. It might seem obvious, but if you put it on wrong, you won't know until you can
't pull the trans up tight and have to pull the trans and correct the mistake. Not that you will, but it does happen.
't pull the trans up tight and have to pull the trans and correct the mistake. Not that you will, but it does happen.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I have a couple of sfi 168 tooth new expired. I will look for them in my shop. Gold anodized. In days gone by I had to have SFI every thing. Like 5 point seat belts expired every two years or even your helmet
168 tooth just needsa mini starter
I changed to a 5 speed.manual transmission. I will look around they are cheap through summit racing if I can't find them
168 tooth just needsa mini starter
I changed to a 5 speed.manual transmission. I will look around they are cheap through summit racing if I can't find them
Thread Starter
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
I have a couple of sfi 168 tooth new expired. I will look for them in my shop. Gold anodized. In days gone by I had to have SFI every thing. Like 5 point seat belts expired every two years or even your helmet
168 tooth just needsa mini starter
I changed to a 5 speed.manual transmission. I will look around they are cheap through summit racing if I can't find them
168 tooth just needsa mini starter
I changed to a 5 speed.manual transmission. I will look around they are cheap through summit racing if I can't find them
Adam
Last edited by NewbVetteGuy; Oct 3, 2018 at 02:20 AM.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
https://www.summitracing.com/parts/sum-g100sfi
Thread Starter
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
Sorry, I ask a co-worker at the shop what happened to those two new in the box flex plates. He said that when that 700R4 tranny was being shipped out he put them on the pallet because he thought they were on the order. This is what they were.
https://www.summitracing.com/parts/sum-g100sfi
https://www.summitracing.com/parts/sum-g100sfi
Adam
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