Flywheels for 3B, 7A and AAN interchangeable?

[Jensk]

I've been told by someone who is supposed to know his audi-parts that the flywheel from the 3B engine (4kg) and from the 7A ( 8kg or something) is a direct replacement.
Obviously this would save some money for those of us wanting a lighter flywheel.

Could also bee that you need to use the whole clutch/flywheel-assembly..

Anyone know anything about this?

[spink]

I can assure you that a 3b flywheel does not weigh 4kg's.AFAIK it is identical to a 7a apart from the part number.Ive not seen any difference's on them before.

[CHEN]

The 7A flywheel definatly works as I have one on my car. I am sure it is heavier though

[~Delta]

4kg for a 3B flywheel? I've posted out 2 3B flywheels within the UK. Packaging was just large bubble wrap, bubble wrap weighs hardly anything at all).

Weight came to 9.75kgs from memory...

[aelred]

You can get them down to about 6Kg by machining

[mcandmar]

7A flywheel and crank pulley are slightly heavier than the 3B items. Cant find the thread about it but here is the one about the pully http://www.s2forum.com/forum/showthr...light=flywheel.

Mark.

[Jensk]

Ok, guess he was off a bit about the wight of the 3B. But what about interchangeability?
Bolt pattern on crankshaft and alignment of the starter motor are the main concerns i can think of.

[spink]

theres no difference

[Billman]

the 3B weighs ca. 9 kg and the 7A 11 kg

If you see the 7A from the back then you also see the Excess material that isnt on the 3B. They both could be brought to the same weight with machining.

[Jensk]

Ok. Thinking of machining mine too. But if either the 3B or the 7A or both are a direct replacement, that would be more "safe"
And also, the AAN engines from 93 and later (or so im told) have a different design of some sort which makes it useless to try to machine them

[~Delta]

AAN are all dual mass (as ABY / ADU). Pointless putting them on any sort of diet.