I've always thought it was cars running 9.99/135mph or better. Here's what my rulebook says:

Transmission shield meeting SFI Spec 4.1 mandatory on any car running 10.99 or quicker or any car exceeding 135 mph. Automatic transmission flexplate meeting SFI 29.1 and flexplate shield meeting SFI Spec 30.1 mandatory on cars running 9.99 or quicker or any car exceeding 135 mph.

The TCI flexplate is SFI 29.1 approved.

I don't see how anyone would even be able to see if the car has the appropriate flexplate or not. How do they check?

Thanks

 

You got two rules there that need seperating:

Transmission shield meeting SFI Spec 4.1 (5 year expiration) mandatory on any car running 10.99 or quicker or any car exceeding 135 mph.

Automatic transmission flexplate meeting SFI 29.1 (3 year expiration) and flexplate shield meeting SFI Spec 30.1 (5 year expiration) mandatory on cars running 9.99 or quicker or any car exceeding 135 mph.

You need a shield at 10.99, you need a flexplate at 9.99.

 

Well I have a transmission blanket so I should be covered.

Any other input?