This flexplate kit adapts a GM Gen III/IV LS-series engine to a TH350, 700R4, or 200R4 automatic transmission, letting a modern LS swap into a chassis running an older GM 3-speed or 4-speed automatic without changing the transmission.
Specifications:
- Custom-fit flexplate sized for the TH350, 700R4, or 200R4 transmission's torque converter bolt pattern
- Crank spacer included to compensate for the LS engine's shorter crankshaft flange depth
- 11mm flexplate bolts included
- Adapts GM Gen III/IV LS-series engines to TH350 / 700R4 / 200R4 transmissions
- Part Number: 712500A
Not compatible with LS7, LS9, LSA, or LSX engines, which use an 8-bolt crank flange rather than the standard LS flexplate bolt pattern.
FAQ
What does the Advance Adapters 712500A do?
It's a flexplate adapter kit that lets a GM Gen III/IV LS-series engine bolt up to a TH350, 700R4, or 200R4 automatic transmission.
What's included in the kit?
A custom-fit flexplate, a crank spacer to compensate for the LS engine's shorter crank, and 11mm flexplate bolts.
Will this work with an LS7, LS9, LSA, or LSX engine?
No. Those engines use an 8-bolt crank flange and are not compatible with this kit.
Why is a crank spacer needed for an LS swap?
The LS engine's crankshaft flange sits shorter than the earlier GM V8 it's replacing, so the spacer positions the flexplate correctly for proper torque converter engagement and clearance.
