Which Flywheel will work?

Im trying to ascertain an application for a 3.4 XK-150 Flywheel.
Does anyone know if the proper flywheel exchanges with any other makes from say 1958? MK1?
Are 3.4L Flywheels the same as 3.8L flywheels?
Are XK 150 3.4L flywheels specific to just that model, or can E Type,MK1,2,340 be used?
Any numbers?

Interesting, I have a Mk7 (3.4) and a 3.8 E-type, both look the same to me, without taking specific measurements or tooth counts, both appear to take the same clutch.

Hi…as far as im aware the mk7, mk9 xk120,140,150 3.4 and 3.8 flywheels have 132 teeth…very close to the 133 teeth from a 4.2 E type…3.8 E types and mk1, mk2s have 104 teeth flywheels…depending what your wanting to do then flywheel can be swapped aroung but starter pinion and starter position needs to be taken into consideration…Steve

C.4809 is the correct flywheel for all XK150.
It was also used on mid-range XK120, std. 140 non-OD, all Mark VII, VIII, IX.
Late XK120 used C.5808 but no explanation is given.
XK140 with OD used C.5808
3.8 MkX used C.12114 and later C.23328
4.2 MkX used C.18517
3.8 E used C.14921 (lightened) and C.20310 (competition)
4.2 E and 420 used C.18517
2.4 Mk1 used C.10087
3.4 Mk1 used C.12114
2.4 Mk2 used C.10087 and later C.23170
3.4 Mk2, 3.4 S and 3.8 S used C.12114 and later C.23328; C.14921 and later C.23345 (for competition)

Better compare diameters and tooth counts with your old one. Others on this forum have gotten into difficulty by using the wrong flywheel, not matched with the bell housing and starter.

Thank You Guys. Exactly the type of information I was looking for.

C.4809 is the correct flywheel for all XK150.
XK120,Xk140 XK150 and Mark VII, VIII, IX have 132 teeth flywheels all except early 120 6 bolt cranks are interchangeable MKI MKII and 3.8 litre E type S type have 108 teeth flywheels all 4.2 cars have 133
don’t fit 133 tooth flywheel in an XK150 as someone here in Australia did after being told 1 tooth won’t make a difference it sounded like a Gatling machine gun

I would think that tooth count on the flywheel would need to be match with the appropriate starter tooth count. I’ve heard 132 to 133 tooth count didn’t matter and thought that strange.
Anyone have starter numbers that correspond to flywheel tooth counts?

once you have correct flywheel you need correct starter motor and bell housing all 3 need to be matched set

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Hi Terry…you have a typo in your post above…you have 108 teeth…should be 104 teeth

4.2 Xj6 auto had 132 teeth flex plate…manual had 133 teeth…they both used the same starter motor becaus the tooth pitch was the same but diameter slightly different…however i believe that the bell houseing fix points were slightly different…as i mentioned depending on what your trying to do you can mix/match flywheels/bellhouseings with new type high torque starters…you can purchase for example a starter that mounts to a 4.2 bellhouseing but fitted with a pinion for a 3.8 (104 tooth) flywheel…Fossways list a wide choice of starters…other manufacturers may supply to order…Steve

YES! @Thorswhisper Note this well.