help finding TDC on a twin plug 3.0 - 3.2

[911Ren20]

Hi,

I was getting ready to do a leak down test. But having trouble finding the TDC for #1.

The engine is modified from 3.0 to 3.2 with twin plugs. The Dis is not the same as the original single plug.

I tried using the screw driver method by leaving it in the cylinder to observe the movement. When i thought it was at the top with the marks lined up. But the leak down results 90% lost. I believe it wasn't at TDC.

I found a youtube video demonstrating a method with a vacuum gauge. But without 1 in hand. Any quick and easy way to identify the #1 TDC?

I have attached photos of the mark on the pulley and the dis. The dis have tabs opposite of each other. the one pointing towards the front make contacts to the lower positions of the contact points in the Dis Cap.

[snbush67]

Rotate it another 360 and try.

[SlateBlueTarga]

Rotate the engine by hand (clockwise of course) and watch the intake valve on #4. As it just starts to open Z1 should be lining up and you should be at TDC #1, providing your cams are in time.

John

[911Ren20]

Thanks. I got it done.

The results were fine.