Exactly, it is hard to build pressure on the compression stroke when the exhaust overlaps and leaks your effort.

How much Cylinder pressure ? 

Lots!

A YouTube link would be better.  Microsoft's trying to get my credit card number...

Oops

It's over 9 MB also.  Pretty bulky.

2 hours ago, 240z70 said:

1982 280zx F54 block (i think that it has dish pistons but not sure.  The engine has a rebuilt sticker: NISSAN JAPAN

Fuel delivery=1970 round SU rebuilt by ZTherapy.

Head:  MN47 (i think, since it has the temp plug below the 5th spark plug).

The P79 and P90 heads have the temperature sensor in the head also.  What is cast in to the head up by the 1 and 2 spark plugs?  It's probably a P79.  Nissan would not put the L24 head on an L28.

You can use the various calculators to estimate CR.  Plus there's another thread by CO discussing the topic.  

Somebody must have modified the Nissan rebuild then.  Not arguing, just pointing out that the "M"N47 head is designed for the Maxima L24E engine, Nissan did not put them on L28's.  .  You have a rebuilt short block with a different head on it.  Or, you actually have a Maxima L24E engine, not a 280ZX engine. Does it have L28 stamped by the 5 and 6 plugs, on the block.

It would also be nice to start your own thread instead of filling up madkaw's build thread.

Here's the thread where CO talks about CR's. 

 

 

Couldn't hear any sound on the embed or on You Tube. Is that just me?

4 minutes ago, Patcon said:

Couldn't hear any sound on the embed or on You Tube. Is that just me?

I just tried it and it worked fine . 

It worked that time

Nice!! How's it feel on the road?