4L80E/SFI Rated Transmission Flexplate

[1-ton]

I put a Jegs in-house brand, 168 tooth, external balance, SFI rated flexplate on my Chevy 350 with one-piece rear main seal. My transmission is an early model 4L80E. The original flexplate had 6-bolts bolting the flexplate to the torque converter, but with this new SFI flexplate only three of the bolt holes line up. The other three in the flexplate appear to be for a smaller diameter high stall converter. My question is...are the 3-bolts going to be enough for the torque converter? I also have a mini high torque starter, and the teeth engagement clearance is perfect for the flexplate. I have tried looking for info on 4L80E SFI flexplates, and there is nothing out there on except for people doing LS1 engine swaps.

 

[Bent77]

Three is fine. I always used grade 8 bolts, but pushed 900+ against those

 

[Babaganoosh]

The 4l60e uses 3 bolts

 

[1-ton]

I was a concerned that if three bolts was not enough that I would have to pull the transmission back off of my truck. I have a PM message to Greg Ducato on this situation as well. Thanks for the replies.

 

[skunked]

My th400 has three. I asked my transmission guy about it and he told me it was fine for my application.

 

[sweetk30]

The 4l60e uses 3 bolts

friend found out the hard way years ago with motor swap . . . .

4l60e is different pattern than 4l80e . . . . had to repull the used motor they didn't tell him come from a 1ton . . . he was putting it in a 1/2 ton . . . if he had known he would have swapped it all over .

 

[b454rat]

3 is fine. back when I put a 454 in my car that was bout 550 horse to a manual valve body TH400 that's all it used. I think most cars/trucks back in the day used 3, so no reason it won't work in later year motors...