[gtofreek]

Getting her all oiled up!



Just under .001" to go. This is the vertical measurement.



.001" to go at the 10/4 O'clock position. Almost perfectly round, but not quite there yet.



All done. This is 10/4 o'clock position, #3.



This is vertical position, #3.



This is typical of all of them. Here's #5.



The worse one is within .0002" at the parting line, otherwise they are all 3.1885, + or - .0001" everywhere else.

[gtofreek]

Here's a pic of it done, and it shows the dowel pin height.



Now on to decking. Here I install what we lovingly refer to as main saddle donuts. Their OD is the same as the main housing bore size, and the ID is 2" for our 2" bar. This is so we can install the BHJ Block-tru fixture to deck it square, and each bank 90° to each other. I can also measure the deck height off of the BHJ Block-tru plate.





The main caps secure it tight.



Next I install some cones in the front and rear, through the cam tunnel. This will allow the BHJ fixture to center between the cam, and crank tunnels.

[gtofreek]

Here is the Block-tru fixture mounted up. The flat surfaces under each deck are 90° to each other. By leveling the block off of these flats, I can re-cut the block square, and 90°. This block proved to be a typical factory deck as it was twisted, and off a fair amount. The left bank was .011" shorter than the right, and had .004" worth of slope in it, front to rear. The right bank also had .004" slope, front to rear.





As you can see, the first pass shows the deck is twisted some. This is the first pass of .004".



A better view of first pass.





Second pass. You can see the twist at the front of the block. This is after removing .008"!

[dataway]

I machined up a set of those pontiac donuts for my machinist in trade for some parts and labor. 3.189 OD x 2.000 ID x 1.000 thick. My block was the first they got used on.

[gtofreek]

Third pass! .012".



All together it took about .0015" to get it to clean up.

Here is the right bank. You can see it's a mirror image of the left bank.







All done.



All holes nicely chamfered now.



Final deck height came out at 10.211" because of the poor deck. I was shooting for 10.215". So the piston will be out of the hole about .004". Nice tight quench.

[gtofreek]

Originally Posted by dataway

I machined up a set of those pontiac donuts for my machinist in trade for some parts and labor. 3.189 OD x 2.000 ID x 1.000 thick. My block was the first they got used on.

Now you can say you make donuts too!

[hurryinhoosier62]

Excellent work, Paul.

[gtofreek]

Getting the block ready for honing. I chamfered and de-burred the bottom of the cylinders.







Then I used a small piece of sandpaper on a split mandrel to run through the oil galleries to clean out the ashy crud, and this is what came out of the lifter bore oil feed holes.

[GRX]

Great stuff. When blueprinting it is always interesting to see how far off factory specs can be.

[vidguy]

Yeah man.. I was away from computers for a day and I missed all this action!. Im stoked. Great work and update Paul. Thanks.. I'm embarrassed about the crud... bBut the old motor ran good, even, like that .........

I'll send all the parts to you right away to do a complete assemble... I don't want to be touching that now...

[vidguy]

I have a machining question..Post #41
The line honing? Is the horizontal axis set somehow to remove some material from both block and cap to assure a similar finish and roundness? Or does it "self center" itself by virtue of some expanding stones on the bar or something?

[gtofreek]

Originally Posted by vidguy

I have a machining question..Post #41
The line honing? Is the horizontal axis set somehow to remove some material from both block and cap to assure a similar finish and roundness? Or does it "self center" itself by virtue of some expanding stones on the bar or something?

The mandrel has guide shoes that can be adjusted for the centerline. Then the stones just make up the difference. As I hone, I sometimes have to change that slightly to make the hole round. Otherwise you wind up with a bore that is .0005"-.001" tighter at the 10/4 o"clock, or 2/8 o'clock position. The hone will hone most of the material out of the out of round spots, in this case, the main caps, since I cut them to make the hole smaller. Very little come out of the block when done right.

I like nice round holes.

[vidguy]

The mandrel has guide shoes that can be adjusted for the centerline

That's what I was imagining. I have heard and read before that you only take a very small amount of material from the block during a line hone..wondered how that was controlled.
Thanks for the info.

I like nice round holes.

..oh man...You're talking about MY block...

[grivera]

Paul- is this level of detail standard practice on a performance build from your shop?

[gtofreek]

Originally Posted by grivera

Paul- is this level of detail standard practice on a performance build from your shop?

Yes! Jeff and myself are very anal about engines. It's our reputation, and being a 2 man shop, we can't afford comebacks, so being anal is a good thing!

[gtofreek]

Got the block in the hone. Then I cleaned all the head bolt thread with a thread file so as to not remove any thread material in the process of cleaning them.



All threads chased.



Then I filled the holes up with lacquer thinner, and ran a brush threw the threads to clean the crud out.



Thread crud oozing out!



Then I miked all the pistons. They all measured 4.1805", for a final bore of 4.185".



Torque plate bolted down with stock head bolts, and number #3 cylinder honed to within .001".

[gtofreek]

They all started out needing about .005" honed out.



I hone it down to around .001" before switching to the finer stones for the final hone grit. In this case, a 280 grit finish for a steel gas nitrided ring. Then it will get finished with a plateau hone brush.



Got it honed to my zero size point. This reading is at the top of the cylinder.



This one is in the middle. This gauge is a tenth reader, meaning each line on this gauge is .0001". I purposely set my cylinder stroke a tad short so it hones a little bit more out of the center[in this case .00015"] because when it cools down, the middle shrinks up more than the top and bottom. This makes it easier to finish it all to the zero when it cools off, and stabilizes. Then I come back after a few hours and reset the cylinder stroke to the correct cylinder length to finish it straight since it won't develop enough heat to shrink anymore.



Here is the bottom.

[gtofreek]

Here's after it cooled down, and shrunk up. Here the top shrunk up .00035".



The middle shrunk up .0007".




The bottom shrunk up .00035", the same as the top. Usually the bottom doesn't shrink up quite as much as the top, but in this case, it did.



Here's the final at the top.



The middle.



And the bottom.

[gtofreek]

Only now, we have these unsightly bore gauge marks. This will not do!



So I do our little Gucci finish on it to get rid of said unsightly bore gauge lines. Then finished with a plateau hone brush.



Here are 4 pics showing the clear distortion of the head bolts, and it's effect on the cylinder walls. This is why engines need to be done with a torque plate. If you notice, each picture is of each corner, and you can see the distortion in line with the head bolts.

[gtofreek]

Here is the piston pin. It is only 2.500" long, has a .150" wall, and is only 122.6 grams!



All done and final washed.





Lifter bores all honed, and WD-40'ed so they don't rust before I can assemble it.