Parts are back from the machine shop - time for some trial fitting. The rods were shot peened, ARP bolts installed, then resized and balanced. There was about a 7 gram spread from light to heavy and some needed end-to-end balancing. The crankshaft was static and dynamic balanced.... about 7 grams removed from 2 spots. The crankshaft damper and flexplate were balance-checked... they were ok.

If you mess with these engines enough, they'll tell you some secrets <img src="/forums/images/graemlins/wink.gif" alt="" />:

While measuring the piston/deck clearance to get a number for deck milling, I decided to check all four courners of the block to see how close it is. The first step was to install a piston stop diagonally across #1 bore, run the piston to the stop, set the gauge at a point toward the front of the block in line with the wrist pin, preload the gauge and zero it:


Then, the piston stop was removed and the crankshaft turned through a few rotations to find the maximum lift at TDC above the deck. The #1 piston was .015" proud at the forward edge of the deck:


After getting the reading, the piston stop was re-installed and the piston run back to the stop to make sure the gauge still read "0" - just a double check to make sure nothing moved during measurement.

Using the same piston/rings/rod combination to eliminate possible variance error, I also checked #2 at the front and #s 5 & 6 to the rear - the four corners of the block. I was amazed at what I found:

#1 = .0150" proud
#2 = .0130" proud
#5 = .0165" proud
#6 = .0160" proud

To make certain there wasn't a geometry error in the wrist pin and bore, I also checked #2 with the piston turned 180 degrees.... same/same.

I would have thought there would be less difference than that. I don't think there's been any core shift because the crankshaft turns too easily and the main bearing clearances are nearly equal from .0018 - .0025.

So, it appears that if I use a .050" gasket, I'll be at a quench height or piston/head clearance of ~.033" unless I have them mill the piston tops, too - probably not necessary, though.

I'll take the block back to the shop tomorrow for deck milling, but before I let them cut the deck, I think I'll have them measure the crank throws - just to make sure the crankshaft is not causing the differences in deck height.

Frank

Oh, what a can of worms I've opened with all of these parts from different engines.... trying to get a decently balanced and blueprinted engine.

It's a good thing I didn't immediately cut the decks from the initial measurements. The differences didn't seem right, so I took the crankshaft to the machine shop, referenced the #1 throw at "0" and found these measurements:

#1 = 0.0000"
#2 = 0.0005" (+)
#3 = 0.0010" (-)
#4 = 0.0015" (+)
#5 = 0.0005" (+)
#6 = 0.0000"

So, my original corner measurements were useless and there was no way for me to determine how to deck the block without getting more information.

Those crankshaft measurements are not real good for someone trying to build a race engine, but I'll settle for a half <img src="/forums/images/graemlins/butwiggle.gif" alt="" /> balanced engine - don't really want to regrind the crankshaft - the rod journals could be ground .010" undersize to true up the stroke differences, but I first wanted to check the rods to see what they looked like.

Came home and put every rod/piston in the #1 hole to see what squirrels lurked there - found this mess as measured proud of the deck (no particular identification of rods #s):

.0160"
.0165"
.0150"
.0160"
.0155"
.0150"

At this point, I started a swap-fest - put the longest rod/piston on the shortest crank throw, shortest rod/piston on the longest crank throw - and on an on and 'round and 'round until I was satisfied that the closest combination of stroke variance and rod/piston length variance looked like this:

#1 = 0.0010"
#3 = 0.0005"
#5 = 0.0010"

#2 = 0.0005"
#4 = 0.0015"
#6 = 0.0010"

And, the measurement of the installed pistons (no rings) above the bore were as follows:

#1 = 0.0150"
#3 = 0.0150"
#5 = 0.0140"

#2 = 0.0130"
#4 = 0.0145"
#6 = 0.0140"

Using the actual amount of piston protrusion expressed as a negative number and deducting the (+) variance totals from the measured clearance then provided a deck height relative to the originally referenced #1 crankshaft journal as follows:

#1 = - 0.0140"
#3 = - 0.0145"
#5 = - 0.0130"

#2 = - 0.0125"
#4 = - 0.0130"
#6 = - 0.0130"

Both decks appear by eye and straightedge to reflect the dimensional variations as the numbers indicate and I CAN see with a straightedge and flashlight the .0015" dip on the passenger side.... BUT, before I cut this deck, I want to check and recheck the math to make sure it's correct.

Surely there's an easier way to do this....... <img src="/forums/images/graemlins/rolleyes.gif" alt="" />

IF the above is correct, I'll still have to mill 4 pistons between .0005" and .0015" if I want all of the pistons to run the same head clearance. <img src="/forums/images/graemlins/scared.gif" alt="" />

What a way to run a railroad......... <img src="/forums/images/graemlins/lol.gif" alt="" />

Frank

uh...bigger wires are better

Did you mention what fuel pressure regulator you will use to git that tractor a runnin?

This one - Holley # 512-504-5

Installed, it looks like this:




Frank

After all that figgerin' and head scratchin', I went back to the old method of installing the #1 rod/piston at the 4 block corners, allowed for the minimal .0005" variance at #2 and #5 crank throws and wrote the dimensions on the decks for the machinist. I don't really like that method because the dimensions aren't taken from the very end of the block.

They have decking fixtures for every Chevy and Ford engine ever produced, but no adapters for imports. Maybe I need to find another machine shop if I want to make a silk purse out of a sow's ear.

Finally, I begged the machinist to try to measure the crankshaft C/L to each deck by using a 12" caliper off the main bearing bores, front and rear to the ends of the decks to try to get a parallel cut. He said he would, but like me, he knows that's not a great method to use. I left the block and told him if the caliper method disagreed with my marked dimensions, to split the difference. That way, hopefully the decks should be within a reasonable margin of error.

Now I get to wait some more..... <img src="/forums/images/graemlins/rolleyes.gif" alt="" />

Frank

The Diamante SOHC block's finally decked.... .003" each side with a slight corrective taper (hope it's right) - never could get an accurate measurement on the deck height, so we took the best guess from the piston clearances. Cleaned and painted the block, installed the freeze plugs and oil gallery plugs:

Installed the Diamante DOHC crankshaft with the DOHC main girdle cap bolts:


Main bearing clearance is .0020"-.0025" <img src="/forums/images/graemlins/kewl.gif" alt="" />
Rod bearing clearance is .0017"-.0020" <img src="/forums/images/graemlins/kewl.gif" alt="" />
Crankshaft endplay is .0040" <img src="/forums/images/graemlins/kewl.gif" alt="" />

The rings supplied with the Wiseco pistons don't have enough gap for a forced induction engine. I tried to file-fit the #1 set - no problem filing the 2nd ring, but the top ring is plasma moly (whatever that is) and way too hard to file. So now I'll wait some more for a ring filing tool to arrive from Summit..... and hope it'll do the job. <img src="/forums/images/graemlins/rolleyes.gif" alt="" />

Frank

I made a simple fixture using a cutoff wheel as the grinder. Use the side of the wheel with the grind direction toward the inside so the flash does not create an issue and finish by stoning the edges. On those rings the ring is hard but the plasma surface is soft.

I thought about trying the side of a cutoff wheel mounted on the bench grinder, but I was afraid the uneven face surface might not work so well. I've already ordered the manual grinder, so I'll wait and see how it works.



That's the truth. <img src="/forums/images/graemlins/scared.gif" alt="" />

Frank

diamnond wheel on the ring grinder? think you'll need it...

I hope not, Eddy...... but I don't know. I didn't want to pay $200 for one of the electric/automatic grinders, so I ordered this manual one from Summit:

Manual ring filer

Right there in the advertisement it says:



So, it has to be true, doesn't it? <img src="/forums/images/graemlins/wink.gif" alt="" />

I wonder how many times the monkey is gonna have to turn the crank handle to fit one ring.......... <img src="/forums/images/graemlins/lol.gif" alt="" />

Frank