valve events, in cylinder ?

ust a query about pinpointing valve events, idling engine, not a standard engine, uprated cams...however bizarrely whoever has built the engine fitted the cam marked exhaust....on the inlet side, and the cam marked inlet, on the exhaust side. genius.

They are probably asymmetrical profiles, so if timed correctly, should not be an issue. However....I just feel something is amiss.

GM 2.2, 4cyl DOHC, Comp cams

As the overlap area is likely to be of little use...I assume EVO and IVC points should be relatively easy to get close ?

So approximately, EVO occurs around 154deg, and IVC around 583 deg ?

IVC seems fairly reasonable. EVO really does seem extremely late. Or am I totally wrong on the positioning ?

154 degrees for EVO is not out of order.

You may want to lower the voltage scale in the capture so the pressure changes stand out more pronounced. In the picture your ruler may be placed slightly later than the pressure change occurs.

The valve actually opens before the in cylinder pressure change goes up, you may want to run the Px script to get more precise data.

Here is an interesting read:

forum-injectorservice-com-ua.translate.g...en-US&_x_tr_pto=wapp

Thanks, so not quite as easy to pinpoint the valve events as I'd hoped.

I'll just have to wait a couple of months til I can get it apart properly to check the cam timing.

Just bizarre someone would put them in the wrong places....it's not like they are clearly marked intake and exhaust !!! lol

Probably symmetrical anyway, but if they used the wrong timing, the overlap would be a few degrees different, as well as overall timing for each cam