505 engine build for street.
 

Getting close to wrapping up a 505 street engine. It has a 4.35" bore by 4.25" stroke. Using a Kauffman block, and Kauffman D-port heads, ported by Dave @ SD Perf. Using an SD Ported factory H.O aluminum manifold. He brought me the SD old faithful cam. Here are some pics of the build so far. Sorry, my Photobucket account is temporarily full so I will have to post thumbnail pics.

Here is the block, and it getting cryo treated. I cryo treated the entire engine.

Getting ready to align hone it, but I see these dents in the brand new main caps! Careless handling I would say. Someone also beat on the sides of the main caps with a solid hammer to get the caps off, and dented the sides all up also.

So I used a file to file the dents off, and make them flat again.

More main cap pics.

After getting them flat again, I re-blued the steel.

Subscribed

Getting it align honed.

Got it honed to 3.1885", exactly in the middle of the spec range. All 5 housing bores measure right on this number, and round within .0001".

Time to square deck it.
As you can see[if you look close] the deck was not perfectly flat, even for a new block. This side had a little bit of twist. The other side was not at 90° to the cam/crank centerline. New blocks are not made to be placed directly into service. They need to be machined for proper heights, and dimensions for the build being done. The people making blocks do not know what pistons are going to be used, or what height it needs to be, so new blocks are just roughly machined, and need to be finished out.

Block needs to be de-burred of the sharp edges. I hate sharp edges. I use a Scotch-Brite pad on a die grinder to de-burr the edges of holes.

Here I am boring the cylinders out. I had to bore them roughly .200" over for a 4.350" final bore. I left .011" to hone out for a superior final finish. You can see the difference in the size of the bore from where it started to where it ended.

Here I have installed our big bore torque plate to hone it with. Then I rough hone it down to about .004" to go, with a roughing stone with T-plate installed. This makes for a nice, round cylinder. Then I hone it down to around .001" to go, with a medium grit stone. Then I use a finer grit stone to finish it to size, and for Moly or steel rings. Both types of rings use the same grit stone. Chrome rings use a slightly rougher stone[the stone I use to get within .001" of final size.

The gauge reading show the size at the top of the bore, the middle, and the bottom of the bore, respectively before final hone. I let the block sit for a little bit for the cylinders to cool off, and shrink up a few tenths. Each individual line on this gauge represents .0001", or about 1/30'th the thickness of a human hair.

Now I go to the finish stone and hone the block to my zero point, which is the final bore size of 4.350".

Here it is .0002" small at the top, .00005" big in the middle, and right on size at the bottom. I will leave it here for now, and let the cylinders completely cool down before I finish it to my zero point. They will shrink up a few tenths.

After completely cooling down, I finished it to size. Here it shows the size at the top, middle, and bottom again.

You can see the size doesn't even vary .00005"! Actually doesn't even vary from zero anything measurable with our gauges.

Time to balance it. Here is a pic of the balance card I filled out. You can see this new, un-balanced crank was off by 205.4 grams in the front, and 63.2 grams in the rear. The reason the rear is not as far off as the front is because the rear counterweight is not as wide as the front, in order for it to fit in the block without hitting. This is why Pontiacs are externally balanced in the rear, normally. I will neutral balance this crank.

This bobweight was 2262 grams. This is why I could neutral balance it. The stock bobweights range from 2400-2500 grams. Here is pics of the crank in the balancer with the bobweights hooked up.

After the first drilling, I managed to nail it, and get the front within .1 gram of the rear. I always do the heaviest counterweight first, as it will change the rear, as you can see by the 3 gram change from the first spinning to the second.

All said and done, I had to drill 3 holes in the front, and 1 in the rear. Went a tad too far in the rear, and had to remove a slight amount from the rod journal area, and a little from the corner of the counterweight, since it wanted weight removed in between the two, where there is nowhere to remove from, so I had to take a little from both sides.

Ended up .4 grams in the front, and .2 grams in the rear. It will be a nice, smooth running engine.

Then I ground a groove in the lifter bore to lower the oil hole for hydraulic roller lifters. You can see the line I scribed 1/4" below the oil hole. This is where I grind down to.

Engine is now on an engine stand, waiting for me to build it. More pics to come when I get them.

Looking good Paul. Those main caps would really bum the average guy out. My fuel cell looked like it had a fairly ruff trip too.