Thread: 355 build HP and Torque?

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Good news,

I got the vortec heads back from the shop, magnafluxing showed no detectable cracks. To minimize the possibility of having the rocker arm studs back out under hard use or higher valve lift, I decided to drill and pin the studs in place. Some people have suggested drilling, tapping and install new screw in studs, but the pinning idea seemed to be more economical and plenty good for my mild build. My intended cam will have only a .500" lift with typical roller lifter ramp speeds.

I picked up a pin kit from Mr Gasket that consisted of 16 roll pins and a drill bit for $13.


With the high sides on the vortec heads it is just about impossible to drill the risers at 90 degrees to the studs and locate the hole 9/16" down from the top per the instructions that came with the kit. By mounting the head in the mill at a slight angle, and positioning the drill bit tight up against the head railing, I was able to start the holes from one side about 3/8" down and to angle the hole so it came out the other side at about the 9/16" position.


The original bit that came with the kit lasted about 2-1/2 holes using good pressure and lots of oil before the tip ground down or chippped to the point and wouldn't drill any more.


I had bought a couple extra titanium coated ones just in case as I had heard from others, that I would need to either have extras or do a lot of resharpening. The first titanium bit worked just fine for the remaining 14 holes.


With the head still clamped in the mill, I tapped the roll pins in. The instructions say to position them so the end nearest the valve is flush, but I found the entire length of each pin was almost exactly the same as the riser width so they mostly ended up with both ends flush.



Here's a shot showing the side closer to the valve


With all the pins successfully in place, I spent some time running a tap and cleaning out all the threads in each head. Looks like my next job is to clean them up thoroughly and reassemble the valves, springs, and rockers. I understand I should probably look into purchasing all new locking retainer nuts for the rockers.

Originally Posted by rollie715

Update:

After cleaning my block, the machinest found a couple cracks in the lifter valley. He reccomended I find another block. Yesterday I picked up another engine off Craigslist. It is the same casting number as my original,14093638 and cast for the roller lifters, but the final machining is not done. I think I can handle drilling and tapping the spider risers and camshaft front retainer plate mounting.

I mocked up a dogbone and lifter and found there was quite a loose clearance where the lifter fits inside the dogbone. So much that even if the dogbone doesn't sit perfectly square with the lifter, it still slides up and down without resistance. At this point I'm thinking of just grinding a little off the backside bottom of each dogbone where the the block is filleted and it should sit and operate just fine.

If anyone has any personal experience with this, I would appreciate their feedback.

Here's a couple shots of the new block:



This new block is not drilled for the mechanical fuel pump either. I'm a little disappointed as my cracked block was almost perfect for what I wanted. I understand there is a jig out there that can be purchased for drilling for the the pushrod and drain hole, but it cost almost $1000. That's ok, I've run electric fuel pumps before and do not object to them at all.

Is it just the photos or what? It looks like the lifter bores have not been cut on the top of the boss for the dogbones to lay down flat. Compare your old block to the new one.

for your build there is no need for the chp-8T but if it makes you feel better .the ch-8 use have them in many builds as with the ch12 in bbc and most dur-bond cam bearing line up. as the way the sbc oils it.s not much of a hi load a dry start deal like a 455 buick . all stock gm blocks run 200.000 miles with out coated bearing on some of the all out race engine i use coated bearings cam. rods.mains. pistons my feeling s on some of the coatings is some what mixed. as over all i have had great luck with no coatings at all . things go way wrong coatings will not save you . look them heads over good the 906 casting they break if there not they soon will seen more bad then good. finsh on head from Gm looks to be done with a dull butter knife to.doing a 350 vtec now in the shop heads were busted seen it many times .i use the RHS replacement far better head. the gm 62 casting seems to hold out better then the 906 seen this head allmost cracked in half

I remember Comp Cams offered at one time a fix for the stock dog bones because the O.E.M. ones had limitations of 5 grand tops.You'll have to talk to their tech line because the last time I looked for them the listing was missing and I don't know what happened to them.

The shop says my block bores will cleanup nicely using a .020 oversize piston. I purchased some Keith Black KB142-020. It has been interesting researching pistons, as there were different pictures on various websites including the computer generated images on the KB site, of what the finished piston might look like. The most common pic was this one which seemed like a good compromise in a dish with a small area for the quench surface, this is what I thought I was purchasing:


However, this is a pic of what I received. I'm thinking this one is actually a better shape, as it looks like the quench area is larger and better matches the shape of the Vortec head chambers:


Here's a shot shot showing the head:


I'm not sure if they will make any difference on my mid performance build, but I'm thinking the pistons I got are a pretty good choice. My revised calcs indicate an SCR of 8.9 and DCR of 8.1.

I got my bored block and balanced rotating assembly back from the shop. My next goal is to assemble the crank,1 rod and piston and check the height from the top of the piston to the deck on each corner, so I can determine if it is square to the crank and to figure how much if any I need to deck the block surface.

I've been doing some reading on Cam bearing installation. It appears there are many opinions out there starting from aligning the bearing oil hole with the block oil hole at 6:00 o'clock to setting it at about the 2:00 o'clock position to aid in the flow and transfer of oil to where it is needed most. Some advice even says it does not matter, as long as the block has a 360 degree groove, the oil will get where it needs to go. I am inclined to go with the 2:00 o'clock position, unless you guys chip in and advise me otherwise.

Here's a photo I found that gives support for the 2:00 o'clock position:

if a 360 groove under cam bearing. i run them all at 3:00. for a low valve spring build on a sbc chevy it will not matter very much so i would not loose much sleep chevy been running them at 6:00 started back when moses was a kid . on the 455 buicks it is a big deal very poor oiling and use the T/A. dur-bond cam bearing that has grooves cut on the back of bearing for ideal clocking for oil or you can rework cam housing bores for clocking stock cam bearings on the 455 or any blocks that are not 360 grooved. finish on deck and heads is a bigger deal on the chevy as the deck and heads can be very choppy like in your photo of that head. the oil only gets were you point the oiling hole in cam bearing . the 360 on the housing bores lets you point it were you want. it matters more were the cam oiling hole is.then the 360 groove. you would not want to point all the bearing holes in at 12:00 up here you would have a hell of a leak and not much oil under the load . if the loading is at 6:00. for some oil ramping under cam getting loaded .... bearing load is down.... that.s were the most of the load is... so off setting the oil hole to load lets oil get under the cam with oil at lower psi and not worry about loading = oil pressure. not oil feeding the cam and drying or shut off oil all the way when cam bearing start to fail but like i said this is more race stuff were there hi loading or poor oiling and the chevy is not bad

Thanks for the input Pat. Regarding the head and block surface, I was thinking the same thing, especially if I end up using a shim gasket and need the smoother surfaces for a better seal.

Today I mocked up a piston and rod and measured the gap between the top of piston and block deck on each corner. Using a straight edge and feeler gauge I took measurements on both sides of the piston inline with the wrist pin. I was able to rock the piston a little in the bore in line with the pin, so I took both minimum and maximum readings at each point. The averages are:
#1 - 0.023
#7 - 0.025
#2 - 0.024
#8 - 0.027
I guess my next step is to determine how much decking I need to do if any and coordinate that with various gasket thicknesses to obtain an ideal quench of 0.040. I'm guessing by looking at these measurements, I won't be able to use a 0.015 shim and still have room to clean up the surfaces, as I would need to be 0.025 in the hole to do that and some corners are already less then that. On the other hand, maybe these measurements are already close enough to work with. We will see.

I'm thinking of taking this information back to the shop and consulting with them as what combination of decking and gasket they suggest. I was thinking I wanted to cut as little material off as I could and he already has some good ideas on what gaskets he would use.

Here's a pic showing how I did the measurements:


I also mocked up the cam and a lifter to see how it fit a dogbone and to determine how much if any machining I need to do to the dogbone seating surface. The dogbone almost sits square except it is held up a bit on the back edge. My plan is to use my own milling machine, buy a bit long enough to reach and to touch up the surface a little and remove enough material on the back edge to get the dogbones to sit square and flat.

Here's a few pics which show it in the lower and upper cam limit positions:

run the piston to TDC then push the piston down so there not rock measurse that then split that should be close .i deck with the BHJ tru -deck setup . that is how i do them . i would deck most all of your number off leave it 010 in the hole then go to a composite head gasket . not a steel shim B.S . no the finish on the heads will not fly it has to be much better then that .for cutting the lifter bores tops a key way cutter works for what

After a few months break, I finally got back to the engine. My brother who has a shop next door mounted the block in the mill and started leveling the area where the dogbones sit. So far it is going fairly well. Here's a rough photo showing the setup on the mill.


Here's a couple showing some details. He just barely took off enough material, mostly in the back, to allow the dogbones to sit square with the bore. He also touched the spider risers and drilled and tapped them, and also the front camshaft retaining plate mounting bolts.

Glad to see you back and making progress! Thanks for the pics too..

I hope this isn't too many pictures. I will probably weed out a few and add more descriptions as I have time.

After getting the block back from the machine shop for the last time, I wanted to clean out all the threaded holes before doing a final washing before the assembly. I was able to do all the 3/8" headbolt and bearing cap holes, the 1/4-20 pan and timing cover and others, and the tapered pipe plugs, but didn't have the correct tap on hand to finish the 5/16" or what ever those mid size holes were, so I will need to clean them up carefully as I bolt on items using them.

I picked up a cheap nylon brush cleaning set from Harbor Freight which came with a bunch of different sizes. Since they were somewhat short, I was able to twist a couple wire handles together to make one long enough for the entire oil passage from front to back through the block.

My good wife let me use the toilet brush to scrub the cylinder walls. Using dish soap and boiling water, I cleaned out every passage I could get a brush into. I also used a little spray-on brake parts cleaner to wash the machining residue from some of the cracks. After alternating between scrubbing with soapy water, and spraying with cleaner, and compressed air, I believe I got most of the debri out of the block.

After multiple scrubbings and wiping with WD40, I finially got to the point where spraying WD40 on the cylinder walls and wiping them clean, resulting in no more gray residue shown on the paper towels.

Here's a shot of the cam bearing tool I picked up on Ebay. This particular one is not adjustable, but is already sized for Small Block Chevys. The moving parts are all brass and are fitted with o-rings to hold the bearing in place. Over all, I would say it seemed to work very well for me.

After reviewing many opinions on orientations of the cam bearings I decided to position them at the 3 o-clock position. (That would be 3 o-clock if the engine was sitting upright in it's running position and you were standing in the front of the vehicle looking at the engine). Since the cam bearings are installed when the engine is inverted, here's a shot showing the hole on the left side and a black mark I added to the top so I could maintain orientation as I got ready to drive the bearing into place.

Here's a shot showing orientation just before I drove the bearing into place.

Here's a shot of the #1 or the front cam bearing. This one taught me a few things. First of all, it has two holes in it, which I chose to orient at 12 and 3 o-clock, but since the holes seem to be spaced greater then 90 degrees apart, it looks more like 11 and 3 o-clock. You may also notice this is not a DuroBond coated bearing like there other 4 I installed previously, as my first attempt at installing the DuroBond one resulted in damage to the bearing when I tried to drive it in from the front without it being perfect square to the block. My good friend at the machine shop had an open box with a single #1 regular Federal ? brand bearing which he gave me, and also advised me to install the front bearing by driving the bar in from the rear of the block and thus more easily maintain good alignment. This necessitated me removing the block from my engine stand to get access to the rear, but resulted in a much easier installation of the bearing without damage. With all the cam bearings in place, I was able to install the camshaft using liberal amounts of assembly lube, and the fully installed cam was fairly easy to turn by hand.

After wiping the main bearing saddles completely clean and dry, I installed all the main bearings in the block, carefully set the crankshaft into the dry bearings, put a piece of green plastigage (.001-.003 range) on each main journal and bolted on the main caps dry. With a three stage torque of 40, 55, and then 70 ft/pounds on each, and then removal of the caps, the plastigage readings were about the same for each main bearing which I interpret to be somewhere smaller then .002 and somewhat larger then .0015. From what I read, that seems to be in the ballpark of where new bearings should be.


After cleaning the smashed plastigage off the journals and main caps, I removed the crank from the bearings, did one last cleaning of each bearings surface and journal and reasembled it back together using assembly lube on all rotating surfaces.

I would have installed the freeze plugs in the block before I put in the cam and crank, but have not purchased any yet, and having today off for President's Day, wanted to make some progress.
Here it is:

Not sure that you can post to many! 'Cause we love'em! And your project is looking good from here! Keep it up!

I went ahead and installed all the freeze plugs, 1/4" pipe plugs and the 3 drive in plugs in the front. I was thinking about tapping the front holes and using pipe plugs as others have done, but at this stage after everything has been cleaned and started to assemble, I decided not to take the chance of getting some of the metal filings in the engine. Instead I just drove in the factory type front plugs and staked them again with a chisel. The commonly forgotton drive in plug under the rear main bearing, I also forgot about and realized the original one was still in there. I didn't worry much about it as I had cleaned and blown out the oil passage fairly well all around it. I did measure down the hole where the oil pressure gauge normally screws in just to verify the plug was installed at the correct level to not cause any oil passage restrictions. It measured just under 8.5" inches down which I believe it correct.

Next step was to get ready to install the pistons in the cylinders. The KB piston directions say that for the type of hypereutectic pistons I have, the top ring gap should be .026" and the 2nd ring gap about .018". After placing a lone ring inside the cylinder, I measure about .015", so the ends would need to be ground. I decided to order a cheap grinder instead of manually filing them with a file.

While I'm waiting for the ring grinder to show up, I moved over and started working on the heads. The new Proform Tall Hite valve spring height micrometer I got needed to be modified to clear the wider valve seal bases on the vortec heads, which I did mostly by just trimming off a little material from the end of the inner threaded part. This reduced the tool's ability to read heights in the upper ranges, but still left it adequate for most typical uses I would need particular on most sbc heads.

Even though others have suggested I not lap the valves if they are already in good sealing condition, I felt more comfortable polishing them a bit with fine lapping compound to remove any rust or grit that may have accumulated in the last year since I disassembled the heads. I did a quick and easy touch up lap, with out removing much material.


After the lapping was complete and everything wiped clean, I miced all the valves to check existing installed valve heights. CompCams says for my cam and beehive springs I would need about 120lbs on the seat which could be made with a 1.75" installed height. After micing them all, most of them measured in the 1.77 to 1.78 range, with one near 1.79. I ordered a hardened shim set from Alex's which should be here any day. I assume I should shim each spring separately to match as close to the 1.75" as I can. The shim set includes thicknesses of .015, .030, and .060, I assume between the .015 or .030, I should have what I need.

The piston ring grinder arrived today, so I was able to get back to working on the shortblock. This little tool was a lifesaver. I can't imagine filing the ring ends manually with a file, as the top rings measured close to .015 and needed to be filed to .026 per KB's chart for the pistons I'm using. The instructions with the grinder said to be very careful not to take off too much, so the first couple rings took a long time as I filed, deburred, and checked multiple times before I got the full gap. After that, I got a better feel for how much I was grinding, and the last few rings were done with only a couple grinds each with the tool.


The 2nd compression rings all measured close to .018 or greater which is right where they should be so I left them as is and didn't need to grind them. I methodically checked each ring gap in the bore it would be installed and then assembled them on their perspective pistons. It took some time to figure out an easy way to put the rings on the pistons, but by the time I was half way through, I had figured out a system and got pretty good at quickly putting them on.


I clocked the rings first with the oil ring components evenly spaced around the circle or about 120 degrees between parts. The compression rings were clocked 180 degress from each other and 45 degrees from the wrist pin. I heard that they all tend to rotate and shift when the engine was running, but that I should avoid having them line up with each other during the initial install. With the bearing dry fitted in place on the rod and a couple pieces of fuel hose over the threads to protect the cylinder walls and bearing journal, a lot of oil on the cylinder and piston, and the ring compressor in place, I was ready to place the new piston in the bore.


With the compressor as tight as I could reasonably get it and square with the block, the pistons were tapped into the bores with the wooden handle of my hammer. I noticed on a few of the installs, the rod bearing would come lose from the rod and either fall off or rotate a little and needed to be reinstalled or straightened before I could fully seat it against the journal.




I checked the first two rod bearings with the plastigage and they both showed a little less then .002 clearance. After that I decided not to check every rod as it seemed like a lot of extra steps to first assemble the bearing dry, do the plastigage thing and then to back off, lube up the journals and reassemble and retorque the caps. I hope I don't regret this in the future, but it does remind me of how impatient I get when some of these details are taking so long and I just want to hurry and move on to the next step. By this point in my evening, it was already getting late, I was tired, and I had spend a lot more time on the ring gapping then I had imagined.


By the end of the evening, most of the pistons were installed and the bearing caps torqued to 35 ft/lbs in a 3 stage torquing. I did notice at this point that the bottom end of the block was getting quite heavy and my homemade engine stand was requiring a lot more manual effort to rotate the block upside down. I think in the future it would be nice to have one of those fancy ones with the rotating cranks to help save my back. Actually I'm thinking I could probably modify my homemade one to bring the engine higher so the center of gravity is closer to the pivot point at this stage in the build. My theory, is that after the pan is installed and the heads and manifolds are added, giving more weight to the top, that the need to rotate the assembly upside down should not be necessary.