4L80 to 6.2 L94

[ncsurveyor]

I asked this question over on the LsX forum but no responses yet. I'm seeing they make a flexplate that will mate a 4L80 (6 bolt pattern) to a 6.2 L94 (3 bolt flexplate). But if I can find a flexplate off of a motor that had a 4L80 mounted to it, would that work on my motor?

[jjzepplin]

I seem to recall reading something about this when I was doing research on LS engine combos. Maybe on LSX Innovations or something. Good Luck.

[LS short box]

I would check with the folks on LS1tech transmission forum.

[roboticjunky]

Flexplate

The 6.0-liter Vortec with a 4l80E transmission is the only Gen III/ IV engine that accepts an early GM transmission without a flexplat adapter or spacer. These vehicles came with the GM spacer and bolts and the flat factory flexplate. These are basically the same components needed for the older transmission swap, just performed at the factory.

General Motors offers the spacer plate and longer bolts over-the-counter. TCI has conversion flexplates for automatic transmissions and kits that include the spacer and longer bolts. You must use a crankshaft spacer, such as the Hughes Performance, TCI, or GM spacer and bolts, or a custom converter must be made with a longer-crank hub. The Bowtie Overdrives LS swap torqueconverter eliminates the need to use a spacer; it bolts directly to the stock flexplate. If you’re installing a used engine, the best solution for the transmission fit issues is to use the transmission that came with the engine. Then all you have to do is fit the transmission to the car.

https://www.cartechbooks.com/techtip...-clutch-guide/