Spark Plug, Compression, Gearing, and Power Feedback

[siteunseen]

1 hour ago, madkaw said:

Did I miss something ?

Train crash in S.C

[madkaw]

3 minutes ago, siteunseen said:

Train crash in S.C

oh- yeah that is scary. I spend many a night sitting in a siding taking a nap. Wouldn’t wake up from that one though

[Hardway]

I will admit, I suffer from a bad case of "while I am at it" so I apologize for jumping from spark plug and compression testing to a possible engine tear down.  First things first is the timing chain.  After thinking about it some more I will probably just replace it with the engine in the car. From there I can look at advancing the ignition timing.  With the timing chain replaced, would I still look at moving the chain to one of the other position to alter the cam timing?

[Mark Maras]

Did you ever take a look to see if the tensioner is in place?

[madkaw]

First things first! Check your valve timing now. You have a stock cam so see how your marks line up. You need to do this to install a new timing chain anyway. Checking to see how the notch lines up will tell you if you do have a valve timing or chain issue. You can peek down in the hole to see if the tensioner has fallen out or something. 

[madkaw]

Looking at your set up again I would think with that trans your z should about break the rear tires loose in first gear under WOT , or should be very responsive . The T -5 has a low first gear that would make up for that diff gearing. It’s hard to analyze such a subjective subject as how fast your z feels or how strong the motor feels. 

A very slack chain would drastically retard your valve timing and move your power band ( higher rpm)into an area that your stock cam would not be optimized.

[Hardway]

I did not see if the tensioner was still in place when I had the valve cover off and should have also checked the timing marks with the engine at TDC.  Oh well.  The car runs and I can move it in and out of the garage.  I really want to get the chain replaced before I do anything else but I will make note of everything before pulling things apart.  The Z will have to wait as I will be doing a timing chain replacement this weekend on my other project, a 1988 Mercedes Benz 560 SEC.

[Zed Head]

12 minutes ago, Hardway said:

 I really want to get the chain replaced before I do anything else 

Some of us were trying to make the point that the chain might not be worn.  In other words, replacing it won't change anything.  Just reiterating...

But, once you take things apart, clarity will ensue.

What engine does that Benz have in it?  Is it one of those that looks like a Datsun engine?  

[Patcon]

I had  boss that had a brand new 560SEL in about 1988. It was a nice car to drive. That car would move if you got on it but you could almost here the fuel tank draining at the same time

[Hardway]

I don't think the 560's V8 is the engine the Datsun L motors were based on.  I believe it was an older motor design.  The engine in my 560 SEC is an all aluminum 5.55L SOHC V8. 

I have only driven the Benz 62 miles as that was the drive home when I bought it.  I knew it needed a timing chain as I could hear it "whirring" at idle so it has been driven some what delicately.  I have been gathering parts from various vendors and plan to get most of it done this weekend, barring any surprises or disasters.  Organization, planning, and cleanliness is key on these engines.

[rcb280z]

Maybe some pics as you perform surgery? I know its no Datsun but I like pics of engine compartments and engine surgery 

Good luck with it!

Edited February 8, 2018 by rcb280z

[240260280]

Merc M180 and earlier: