Using a 3.4 Flex plate on 3.8 Engine

Does anyone know if the 3.4 flywheel will work with a 3.8 engine? The Mark IX automatic I am working on has an older, and incorrect, 3.4 engine. I have a freshly rebuilt 3.8 sans flywheel.
Pat H

I take you are converting to a manual box Pat so, what gearbox / bellhousing do you intend
to install ?
Peter B.

The same auto box that’s in the car now

v/r

Pat

J. P. (Pat) Harmon, DCDR-16

Just a sraight exchange, the ring gear is integral to the converter, the flex plate, ( I think thats what you blokes call it ) bolts straight on. Make sure the toe bearing (if fitted) is removed from the 3.8 crank.
Peter B
Edit
You might have trouble removing the two dowels that locate the flex plate which is not that
thick, and easy to distort. later dowels are threaded 5/16" UNF to allow a slide hammer or bolt to be used to extract same… So if a prob drill and tap the dowels. If you use a setcrew
to extract make sure it abuts the oil return housing not the sump.

Thanks Peter! I’m hoping the DG250 is OK. Car’s been sitting in a garage since 1989!

v/r

Pat

J. P. (Pat) Harmon, DCDR-16

I put a Factory light weight E-Type flywheel on the back of a 3.4 XJ6 Auto , it bolted straight on !

Hi Pat just a thought, it might pay to change the title to read ‘Flex plate’ rather than flywheel.

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