Will a 3.4 manual bellhousing bolt to a 3.8 (or 4.2) block?

Will a 3.4 manual bellhousing bolt to a 3.8 (or 4.2) block ?

Should do the 3.8 and I would hazard a guess the 4.2 as well as I don’t think they changed the blocks, just the bore spacing.

I just put a 4.2 into my 3.4.

Although the installed gearbox is a W58 with a Dellow bellhousing, the 4.2 fitted perfectly.

So yes, it should all work.

Yes but you need to consider starter motor fitting…eg a 4.2 starter will fit a 3.4 bell but be in slightly wrong position to mate to the 4.2 flywheel…Steve

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Interesting, as I have a short stud 4.2 in a '51 MKVII with the original SH gearbox,
not sure what starter is in there, or bellhousing, that will be getting dismantled sometime soon

Do you or anyone else happen to know if the 3.4 bellhousing and starter will engage with the 3.8 flywheel, and/or whether the 3.8 Starter and flywheel are the same as the 3.4 items ?

Hi Tony…cant answer that…you would need to look up parts catalogues…count teeth on flywheel and measure diameter…Steve

Hi Tony. What range of cars are you referring to. The xk / MK7, 8,9 or the later MK2 range.?

Yes. BUT you have to be careful to match the starter and then the flywheel to the bellhousing you have. But, yes, any XK bellhousing will physically bolt up to any block.

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Early 3.4 flywheels have 132 teeth, 4.2 flywheels have 133 teeth. Somewhere between the two are models with 104 teeth.

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3.8 had the 104 teeth flywheel…Steve

Thanks gents,

I did some research and came up with the 104,132,133 teeth flywheels

I have a complete MK7 JLN Overdrive trans conversion set out of a MKVIIM, just checking, whether it fits the 3.8 MK9/XK150 ) as I think I may have been told

Would I be correct in assuming a 3.4 Flywheel will bolt to a 3.8/4.2 crank ?

I know it is highly desirable to have a matching bellhousing/starter/flywheel

It will not fit MK1/2 or any other models I know of

Converting MK7-9 and XK140-50 to MOD Gearbox - Saloons - Jag-lovers Forums

Any flywheel will bolt to any crank. (Very early 3.4 were an exception, I believe)

It’s important to think of flywheels, bellhousings and starters as interchangeable as an assembly. Swapping one without consideration for the other can easily lead to grief.

You also need to consider how the clutch actuation takes place berween the specific chassis and the chosen assembly. Obviously, there are RHD and LHD versions as well as mechanical and hydraulic versions.

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