I know nothing about flywheels

[NeoMishMoo]

If this has already been covered please point me to the thread, I searched and searched and only found one thread about shaving down flywheels.

So I am swapping engines and I have 2 spare flywheels and I thought that I would have one of those flywheels resurfaced and lightened and have it ready and waiting on the swap. However these two flywheels are different and I don't know which one is right. One is out of an 86es and the other is my original one out of my current car: 87 eta.



When I first got my car at 16 I didn't know squat about cars, especially flywheels. We took my car to a transmission shop and for some reason we had to get a flywheel out of a junkyard car because the transmission guy said my flywheel wouldn't work with the clutch/pressure plate that he had ordered, something about the parts for my flywheel weren't available.

[handysmurf59]

Nice paint job on that manifold!

[tonytony]

the flywheel on the left looks to be a single mass flywheels so that's the one you'll need to shave and lighten and resurface if you want to use a getrag260 transmission

[NeoMishMoo]

The manifold is a junk one that I was just playing with.

The flywheel on the right is the one that I had in my car originally.

Anyone know why a transmission shop wouldn't be able to use my original flywheel? I can't remember why but I had to get one out of a junk car.

[NeoMishMoo]

I'm thinking that the transmission guy from years back couldn't get the clutch kit for my single mass flywheel, and instead got me a dual mass? or maybe it is the other way around? How do you tell the difference between single mass and dual mass flywheels?

[tonytony]

i dont know why they woudlnt' be able to find a clutch for a single mass, but i'm no mechanic. To tell the difference is single mass looks like one piece of metal, dual mass looks like two pieces of metal sandwich together

[leland21]

You have to use a different pressure plate with one opposed to the other, the bolt holes are different.

Personally i would get the single mass one shaved down, it's already lighter. Just buy the clutch kit for which ever one you use. They will both work just with different parts.

[NeoMishMoo]

So this is twin mass correct?


And this is single mass? Right?

[NeoMishMoo]

I bought my clutch/pressure plate from bavauto and when I asked them about the different flywheels they told me this:

e30s built before june 86 have single mass flywheels, all other have twin mass flywheels. Also it is not a good idea to try and lighten dual mass flywheels, however they didn't say why it is a bad idea.

Is this all right? Sounds questionable to me.