Thread: 355 build HP and Torque?

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Now that I can post pictures, here are a few:
It all started in September of 2011 when a 67 Camaro caught my eye on Ebay.
Here it is being delivered to my place of work:


Upon further checking, I discovered it only had a 2-barrel 283 installed.


My quest to find a bigger motor led to a 275hp 327 and finally to a good deal on a 350 out of an 89 pickup along with a couple of 700r4 trannys.:


I set up shop inside an 8'x12' storage shed in my back yard, as I don't have a regular shop or even a garage:


You can see the remnants of both the 327 and the 350 parts on the wall:


Having no clue what I would find, I began dissasembly. The engine was not a factory roller cam, but was cast and mostly machined to accept one. The front cam retainer plate mounts were machined and tapped: (sorry for the blury picture)


The dogbone surfaces were already machined:


The spider retainer risers were there but needed to be drilled and tapped, a job which I figured I could handle:




Upon further inspection, even though this engine was originally fuel injected It was already set up for a mechanical fuel pump and had a plate bolted over the area.


It was already machined and predilled for the push rod that would run a fuel pump. I tried the push rod that came in my 327 and it slid in.


Also the pump adapter plate from the 327 bolted right on. As long as my new camshaft has a lobe for the fuel pump pushrod,(which is does) I should be in business. This is perfect!


I already had an Edelbrock 1406 600cfm and planned to reuse it if it fit the final plan. So far, so good, looks like this engine block will be just the ticket for what I want to do.

As I continued my research, I started developing a plan. I wanted to end up with a build that would ressemble an original era correct engine, but to have the advantages of the new technologies. I heard the Vortec heads were a great improvement, and found a very low mileage set at a swap meet. They showed very little wear and didn't leak when I did a chamber volume cc check. The plan is to have them magnaflux checked for cracks, pin the studs and install a set of high lift beehive springs.



I cc's the heads and found 2 chambers measured 64.5cc's, and 6 chambers measured 65.5cc's. Should be good enough as is for a street motor. I removed all the rockers being careful to keep each original rocker together with it's own pivot ball, I strung them all together on a string to keep them matched. I marked each valve top with a permanant marker so each one could be put back into it's original location in the heads. Lucky for me there were unique casting marks on each head to tell them apart when they get back from the machine shop to be magnafluxed. One had a "1" and one had a "3" as part of a separate casting mark. Other then that, they both were the same "906" castings. I drilled some holes in a 2x4, marked it for each valve, screwed it to the wall and put all the valves in it for orderly storage until they are ready to put back in the heads:


I wanted to make them look correct for the era, and researched available finned aluminum valve covers, but found they were kind of expensive. At this point I'm thinking the factory 89 covers could be cleaned up and painted silver or aluminum color and probably look very nice. You may have noticed an aluminum set in a previous picture, which I picked up at a swap meet, but they are a very tall set and may interfere with my planned power brake booster and I think the very tall look detracts a little from the factory original look I'm going for.

Are you aware that there are adapters available to convert center-bolt heads so they can accept the older-type valve covers? If you want to make your engine look period correct, check them out. Here's a link:

Valve Cover Adapter for Center Bolt Heads - Speedway Motors, America's Oldest Speed Shop

Originally Posted by rumrumm

Are you aware that there are adapters available to convert center-bolt heads so they can accept the older-type valve covers? If you want to make your engine look period correct, check them out. Here's a link:

Valve Cover Adapter for Center Bolt Heads - Speedway Motors, America's Oldest Speed Shop

Thanks Lynn,
Yes I checked those out, but at this point my budget is wiped out by all the main engine part upgrades. I may eventually go that way, but am looking for a cheap solution to get me through this initial phase. I have also looked at the finned aluminum vortec style, with the Chevrolet script which only use the end two center bolt holes, which on casual look, appear fairly correct. I'm still using the original factory rockers, so the smaller covers should still fit. Like these:

Originally Posted by techinspector1

Let your machine shop guy supply the bearings, he knows what is currently the best choice to use.

I dropped the block and heads off at the machine shop today.

Shop guy recommended Durabond brand cam bearings. I ordered the high performance style with the Teflon coated surfaces. Supposed to hold up to higher pressures and temperatures if needed.

Work requested was:

Hot tank block and heads
Magnaflux heads
Measure bore size and I will provide pistons accordingly
Bore cylinders using torque plate
Surface deck according to my stacked component measurements to achieve 0.040 quench, and be parallel with crank.
Install pistons on rods
Balance complete rotating assembly

With his existing schedule, this may take 2-3 weeks to complete.

It was nice to talk to a real person about the details of this project.
We hit it off very well.

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

on them GM retro covers are neat but how are you going to vent the engine and add oil the engine must breathe just like you. on the 906 and new GM heads the stock intake valves in many cases just will not clean up on a re grind if so the margin is very thin so it.s cheaper and smart to start out with new valves i do not spend much time cleaning valves when a new oem valve is less them 6.00 each you get a better job and no worrys of pull threw or cupping . the ex most of the time do have abit of margin and will take a clean up . if stems are not worn threw chrome on the valve stems

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.

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.

Originally Posted by techinspector1

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.

Richard, you are correct, they are not cut.
However, my plan if they are a usable height such that the dogbones sit low enough to encase the top portion of the lifter, is to modify the dogbones to sit flat by grinding a small bevel on the bottom rear edges. The existing block surfaces are already mostly flat and perpendicular to the lifter bores, except for a little radius on the back edge. Instead of machining out that radius as the factory did, I was planning to modify the dogbones a little. The slots in the dogbones already have plenty of extra room in them to not bind on the lifters even if they sat at a little angle, so I figured with a little bit of work, they should be just fine.

As usual, I am the novice here, so if I'm missing anything, please advise me. If I have to, I can have the surfaces machined, the same as the factory, but I'm hoping to spare that added expense if I can.
Rollie

Never tried it personally, but my best instincts tell me that the factory would not have spent one thin dime more than they had to in order to make the dogbones work. They spent additional money to cut the top of the guides for some specific reason. Of course, us hot rodders have been altering what the factories produce ever since there have been factories, so do whatever you think you can get away with.

EDIT-
Surfing for info and came across this....
http://www.jalopyjournal.com/forum/a.../t-478632.html

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: