Difference between ABY and ADU cam sprocket

[UrS4boy]

or "toothed belt pulley" in ETKA speak?

The ABY (and AAN) sprocket/pulley PN is 034 109 105

The ADU (RS2) sprocket/pulley PN is 034 109 105 B

Is there a serious difference? (Key way cut a few degrees different?)

Are there problems running the RS2 exhaust cam with a ABY (AAN) sprocket/pulley?

Dave F.

[UrS4boy]

Nobody?

[yodasfro]

Shooting fish in a barrel Dave. LOL

[S2central.net]

AFAIK, plenty of folk of tried different exhaust cams (like 7A and ADU) on the ABY/AAN camshaft pulley so I don't think there are any deimensional differences. I can't be 100% certain - only a photo of both side by side will prove either way.

Paul

[UrS4boy]

Shooting fish in a barrel Dave. LOL

?

[UrS4boy]

AFAIK, plenty of folk of tried different exhaust cams (like 7A and ADU) on the ABY/AAN camshaft pulley so I don't think there are any deimensional differences. I can't be 100% certain - only a photo of both side by side will prove either way. Paul

I realize the people have tried 7A and ADU cams in AANs and ABYs. However, at least in the case of the ADU cam, I wonder if the ADU cam sprocket doesn't advance or retard the ADU cam just a bit, relative to the AAN/ABY cam sprocket. A photo of both sprockets would be excellent. I wonder where I can find one?

[Rusty]

From what I've read elsewhere I think that the ADU cam wheel retards the timing 10 degrees, not sure if this is a physical change or just electronic. The ADU and ABY inlet cams are the same but the exhaust cam is higher lift and less duration.

Running the RS2 exhaust on the ABY wheel will give a later opening exhaust valve with the same closing point and more lift.

See here for cam specs.

[Mixu]

The difference is only on the hall sensor "cap". I measured it myself. Cap has ~5 degrees difference. But I can't remember which way.

I can take pictures of both this weekend. My cylinder head needs work and I have couple ABY/AAN sprockets lying on the garage table. And the engine has ADU sprocket.
And I'm installing adjustable sprocket anyway.

[UrS4boy]

The difference is only on the hall sensor "cap". I measured it myself. Cap has ~5 degrees difference. But I can't remember which way.

I can take pictures of both this weekend. My cylinder head needs work and I have couple ABY/AAN sprockets lying on the garage table. And the engine has ADU sprocket.
And I'm installing adjustable sprocket anyway.

Probably advanced. In any event, please take and post a photo, it will be good for the archives.

[S2central.net]

Yes - some photos, clearly showing (or notated) with part numbers would be great Mixu. Thanks, Paul

[Mixu]

Forgot to post the iamges about the cam gears. But here they are, sorry about the image sizes.
First image shows part numbers, not well though.
Left is AAN/ABY 034 109 105
right is ADU 034 109 105 B (the B is on the hall sender timing sender plate)

[Mixu]

Second picture shows the other sides.
Left ABY
Right ADU

[Mixu]

Upper is ADU
Lower is ABY

[Mixu]

Here also Dahlback cam gear.
Up left ABY
Up right Dahlback
Down left ADU

[Mixu]

And the other sides