RS2 timing marks question

[Avantus]

Hi all,

I'm doing a timing belt job on an RS2 with the following situation:

119C belt with 150 teeth (correct belt)
29-teeth waterpump (wrong, should be 26, but recenlty replaced by the looks)

Turned the crank to show the mark trough the window of the gearbox.
With that done the marking on the cam sprocket sits perfectly in the V of the
cam cover... I know it should be well half left of the V.

Now in my understanding it is the cam/cam sprocket itself that causes the need
for the alignment slightly left of the V? It definately is an RS2 sprocket btw (mark B on it)

I took the cam cover off to check the dots on the rear of the cam chain sprockets, and they are perfectly towards each other...

Any input?


Thanks!

Steve

[riche164]

Without sounding like a bolou# did no 1 here ever hear of tip ex mark your cam and crank get the write parts change them and put them back together simple no locking tools just comon sense why over complicate things

[V6quattro]

I think the bigger waterpump is the problem.

[andy10v]

Without sounding like a bolou# did no 1 here ever hear of tip ex mark your cam and crank get the write parts change them and put them back together simple no locking tools just comon sense why over complicate things

That assumes the that it was correct before you started, that is often not the case with a used car.

[Error404]

It is the smaller RS2 water pump sprocket that causes the "half tooth out" issue, due to the smaller diameter

[Avantus]

Ok thanks! So installing a new belt is fine.
I'm going to keep the waterpump too then, since the tentioner can cope with the 150 teeth belt + 29 teeth pump.

Cheers!

[V6quattro]

But your timing is off a few degrees now. I would press over the adu gear.

[Avantus]

Why would it be off?

The timing marks on the cam sprockets are perfect towards each other, and the stripe in the window of the bellhousing also sits perfect.... so if you put a belt in between those 2 it should be perfect no?

[Rusty]

If it all lines up the you've done a better job than Porsche / Audi

Not sure on the tolerances but there are plenty of ABYs running stock engines (water pump, can pulley, 151 belt) with RS2 maps and this causes no issues. Depends if you're using an ADU cam pulley with it's 10 degree different hall sensor window.

The thing to focus on is crank to cam alignment. If it all lines up then you're 7 degrees out at the cam compared to stock ADU... it can't handle 14 degrees (1 tooth) but it may be fine...

[Avantus]

So an original RS2 setup doesnt have the dots on the rear of the camshafts aligned?

[V6quattro]

Why would it be off?

The timing marks on the cam sprockets are perfect towards each other, and the stripe in the window of the bellhousing also sits perfect.... so if you put a belt in between those 2 it should be perfect no?

If you use a larger water pump pulley the timing is off. If you hold the crank in position and increase the size of the water pump pulley it will start rotating the camgear.

When my had my car on the dyno and we adjusted the cam a few degrees it made a huge differens.

So if it was my car I would have the cam timing as Audi did it. I'm sure getting the cam timing a half tooth to the left is how the adu cams perform at there best.

[V6quattro]

But don't you have the original water pump anymore? You can press of the rs2 wheel and use it on the new pump.