SFI flexplate mandatory in all v8s Jan 2024

[4543]

I’m not sure if it’s the 7000 rpm or the converter hitting at 5800 instead of the 4400 people used to use! I think the converter hit stresses the flex plate more than going down the track but it could crack at the hit and come apart down track. The stock GM flex plate that I saw has the ring gear only welded on one side. The certified appears to be welded on both sides of the ring gear and possibly more welds. Both of mine are certified but have been in my cards for years. I’m thinking I’m going to replace them. Mike McMahan 2543 H/SA

[Billy Nees]

Now just to be "fair", this ruling is going to apply to all V8 bracket cars also right?

[Chevy55]

Originally Posted by Billy Nees

Now just to be "fair", this ruling is going to apply to all V8 bracket cars also right?

2023 NHRA RULE AMENDMENTS

Beginning January 1, 2024, SFI 29.1 flexplate mandatory on all V-8 vehicles. Any car running quicker than 9.99, SFI 29.1 automatic transmission flexplate and SFI 30.1 flexplate shield mandatory. See General Regulations 2:12, 2:14.

[Tom Goldman]

Having repaired several racers cars after a flexplate explosion I cannot understand why anyone would be against this rule which should have been in place years ago.
I've seen headers sliced off, frame rails cut in half and floors with shrapnel sticking thru within inches of the drivers feet. . Not to mention the possibility of severe injury to track personell or even your crew menbers.
Jim Bailey is correct . the 2 step is well known for causing other issues like broken oil pumps and pickups..

[Mark Yacavone]

Originally Posted by Chevy55

2023 NHRA RULE AMENDMENTS

Beginning January 1, 2024, SFI 29.1 flexplate mandatory on all V-8 vehicles. Any car running quicker than 9.99, SFI 29.1 automatic transmission flexplate and SFI 30.1 flexplate shield mandatory. See General Regulations 2:12, 2:14.

Yes..Okay.
So how does that apply to U/SA 273 Mopars?

[joe huestis]

Originally Posted by Mark Yacavone

Yes..Okay.
So how does that apply to U/SA 273 Mopars?

or to a 267 chevy U/SA ?

[Paul Precht]

A Mopar flex plate barely extends a 1/2" beyond the bolt circle of the converter, if it explodes it's because the converter exploded otherwise not really possible.

[Mark Yacavone]

Billy , Just mark your tech card with the ATI 400 Pontiac model.
If anyone asks , I'll say I saw you put it in .
I'm sure you will anyway..it's only a deuce , plus re-balancing
Still not sure if you can add or take away weight on an SFI approved flex.
Anybody?

[Bob Bender]

I have always used a SFI wheel. Just thought it was a good idea.

[L.Fite]

Originally Posted by Mark Yacavone

Billy , Just mark your tech card with the ATI 400 Pontiac model.
If anyone asks , I'll say I saw you put it in .
I'm sure you will anyway..it's only a deuce , plus re-balancing
Still not sure if you can add or take away weight on an SFI approved flex.
Anybody?

You CAN...
I have in the past... (removed weight for balance)
Honestly never gave it a thought, just part of building a motor...
Will it recertify?
Don't know...
THAT is the true question...
Hmm...