CLASS RACER FORUM - flexplates

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Re: flexplates / shields

so just to understand rule there is no expiry on existing SFI flexplates & if you are using a aftermarket transmission case such as Reid , ATI etc you still need shield or blanket ?

Pete, I hope not, and I don't think you need either if your "Super Case"
comes with 2 SFI #'s. One for the regular shield or blanket area & one for the Flexplate Shield. I just bought an ATI unit to get rid of the aggravation
of having to worry about them, and taking them on & off.

J.R.

I checked the Reid transmission site & their aftermarket powerglide case does Not need a Shield as it has a SFI rating of 4.1 & does Not need a Flexplate shield as has a SFI rating of 30.1 .. just need the answer on expiry dates of existing SFI flexplates

Ah ... just found on nhra general regulations for superstock 3 Years SFI expiry I believe

SFI approved Flexplates to spec 29.1 have a 3 years from date of certification service life. Some manufactures will inspect and Recertify.

SFI approval 4.1 is for transmission shields and cases. They are one and the same for certification purposes. This is for the main case not the torque converter flexplate area. Reid, Dedenbear, ATI, BTE, Trans Specialties and JW are examples of aftermarket cases that are SFI approved and there are others. All of those if undamaged or unmodified usually can be inspected and recertified. Stock cases are not SFI approved and must use an Aftermarket Transmission shield or blanket if Required. SFI 4.1 certified parts have a 5 years from date of certification service life.

SFI approved 30.1 is for Flexplate shields and bellhousings. They are one and the same for certification purposes. This is for the area of the bellhousing that covers the Flexplate area. Reid, Dedenbear, ATI, BTE JW, Trans Specialties are examples of aftermarket bellhousings that are SFI approved and there are others. It can be part of a one piece case or separate bolt on bellhousing. Stock bellhousings are not SFI approved and must use an Aftermarket Flexplate shield if required. TCI and others make these. Most aftermaket bell housings and flexplate shields can be recertified if undamaged and unmodified. SFI 30.1 parts have a 5 years from date of certification service life

One piece cases like Reid and one piece shields like CSR will have both SFI 4.1 and SFI 30.1 both of which need to be recertified at 5 year intervals.

Steve, I Thank You for all the valuable information you provide to the CR site. Much appreciated !!! :)

When you send your trans case in for the 5-year recert, don't forget to include the 'liner' along with the cleaned aluminum case. It's an arched steel plate that does the heavy shielding work.

I made that mistake the first time.

Do you have to have a trans shield and a blanket now in stock. plus the certified flexplate.

Quote:

Originally Posted by Randy Guest (Post 692069)

Do you have to have a trans shield and a blanket now in stock. plus the certified flexplate.

Also curious on this. I think there is a speed/class threshold for it.

Any car running quicker than 10.99 must be
equipped with a transmission shield meeting SFI Spec 4.1.
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