John..

5: 95%
6: 95%
7: 95%
8: 95%

Are these good, considering the engine has not yet even been started? It is still on the stand and I ran a quickie on it earrrly this AM after tightening the head down to spec.

I'd expect to see those numbers run up into the high 90s on a warm engine. I'd like to think these numbers are good.

The other head goes on tonight after I dig out all of the crud in the stud thread holes (compliments of the honing process).

Tony

Sorry i cant answer your question, but it sure seems like your moving a long!
keep us posted! <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />

Jim bailey - 928 International

pretty much meaningless at this point in time . current numbers depend on what oil/lub you used when installing the pistons / rings . Does tell you the valves are sealing . You need to run it enough to break in the rings circulate oil etc..

John..

I had a bit of leaking past the valves but a few pops with the rubber hammer and they sealed up. What a delightful sound at 1:00 AM when everybody is trying to sleep.

I suppose this is because they were just lapped and they are not yet fully seated in either.

Once it runs, the numbers should come up. I'd always heard this test needed to be run on a warm engine, not a cold one.

I used Redline synthetic lube and Mobil 1 synthetic on the bores (per Millennium's recommendation). I'm sure this is contributing to some of the leak because the Redline is pretty heavy.

It will be broken in on some conventional oil for the first 1000 or so miles, then switch to M1 15 W50.

All in all, I'd say 95% is a good number for now.

Jeez, I sure hope I got all those wrist pin retaining clips in properly...my brain is worrying about everything now as the project nears completion. With any luck, it will be back in the car on Saturday.

Jim bailey - 928 International

John..."Jeez, I sure hope I got all those wrist pin retaining clips in properly...my brain is worrying about everything now as the project nears completion. With any luck, it will be back in the car on " ........ one of the "tricks" at the Porsche dealership was to wait until a tech had an engine nearly complete ......then drop an extra wristpin clip on his work bench where he was sure to find it.....If they liked the guy they would tell him about the "joke" before he took the engine all apart to see which piston was "missing " a clip .

Lagavulin

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">one of the "tricks" at the Porsche dealership was to wait until a tech had an engine nearly complete ......then drop an extra wristpin clip on his work bench where he was sure to find it.....If they liked the guy they would tell him about the "joke" before he took the engine all apart to see which piston was "missing " a clip .
</font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Doh! <img border="0" alt="[hiha]" title="" src="graemlins/roflmao.gif" />

John..

That is cruel. I had my Mother inspect the circlip placement with a magnifying glass before installation.

So, I checked them once..
She checked them once...
Then I checked them before I put them in the bore

All should be fine, but one coming loose would SUCK!

In addition, getting the JE wire locks in is like wrestling a snake, nasty little things.

My Brother is in town this weekend, so tonight we should get a boatload done and be lowering the beast into the car by Sunday at the latest.

I'll be taking lots of pictures of the engine for you guys.

Susan K Thomas

This is Marc using Susans computer!

Most of the engines that we build leakdown less than 2% new and dry (using a post build washdown of solvent)with heads installed. The heads typically seal 100%. Chevys are the same, in fact, if the block is bored right, the rings seal under hand cranking!

A recent test on a 3 year old 6.5l with extreme usage indicated in 7 cylinders leakdowns less than 3% in one cylinder, less than 2% in 6 cylinders and 8% in one. The 8%'er had a big scratch due to a ceramic chip from a broken spark plug falling into the engine.
\

Typical leakdowns post run in are in the 1-2% range.

5% is a high number. I would first check the gauge...we have three just for this purpose (Matco, Snapon and Tava), all read within 1% or less of each other. Feed pressure is 100 psi even.

I would run the engine, and test the worst cylinder every 1 hour of running hard and monitor the results. There may be particulars with running the coatings that you will become intimate with shortly and this may be one.

Good luck,
Marc

John..

Well, the gauge is my home built unit. So no telling on calibration. If I open up the choke the number will come up.

I ran the other side, and got the same results.

I'm sure it has much to do with the redline assembly lube I used on the rings and the bore. Millennium recommended a good synthetic lube. I wiped the cylinders with M1 15-50, then put some synthetic lube on the rings and skirts. Other swear by just using only oil. I did not want to risk damaging the Nikasil and I may have to live with a slightly longer break in. Once this melts out and the rings start to seat a little, I think it will be fine.

Lagavulin

I think the fact that all cylinders are consistent is more relevant than the actual numerical values themselves.

John..

That is what I wanted to confirm....even numbers.

jpitman2

I have heard of small high revving engines coming to grief on wrist pin clips. The original clips were G shaped, with a tang pointing towards centre, so you had something to grip on to pull them out. Apparently at speed (20k+) the tangs would vibrate enough to break off, and go through the works, wreaking havoc along the way. I dont think a 928 revs high enough to do this though??
jp 83