Thread: 350 to 383 Clearance and assembly.

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The center 4 rods have problems. Even with these Eagle SIR rods you have to clean up a bit of the bolt hole boss that is at the extreme upper end of the rod big end. I used a bench grinder to perform this task, then I polished the grind area on the wire wheel. I placed the piston in a sock for the grinding, this keeps the piston clean. Once you finish grinding, clean the bearing and rod that was exposed, wipe it dry of the solvents and re-lube. Reinstall the rod and test for fit. Repeat this all 4 of the center rods.

Take the rod and grind the bolt boss on a 45 degree angle and round off the grind and radius it a smoothly as you can.

Once you get all 4 rods to fit perfectly, you want to spin the crank by hand about 20 times and keep re-cheacking. OK, now your happy that you have not assebled a bomb, lets start looking at clearances that are measured without a coat hanger. Start with the easy one, rod side clearance. Get a feelers guage and push 2 rods to one side and measure the gap on the other side. Like this:

Here is where you make or break a build. Oil pressures are made or lost here. How many times do you here of the guy with a high vol or high pressure oil pump that makes 80 lbs of oil pressure cold but 30 lbs once it warms up? Here is why. His bearings are giant oil bleeders! If this step shows a problem, you need to report this to the engine machine shop and have them get this corrected. If it means turning a crank, so be it. Same on rods, its goto be right. Remember, high vol/pressure oil pumps are bandaids over a problem, not a fix.

OK, take and remove at least a couple main bearing caps and slip a chunk of PLASTI-GUAGE axially onto the crank journal. Reinstall the main cap/bearing and torque the bolts in 3 steps upto the recomended torque of 70 FT/LB. DO NOT TURN THE CRANK! Remove these main bearing caps and use the plasti-guage paper to read the width and write down your results and on what main you read from. If you do 2-3 of them and they are within tolerance you can stop here and repeat the process with 3-4 of the rod caps. Just be carefull not to drop a piston on the floor! when you take the rod cap off and there are no rings installed the piston will zip out of that cylinder and bounce acrossed the garage floor in the blink of an eye! Keep clean gloves on for this bearing and piston touching, cleanliness is godliness.

Any time you are grinding or creating dust around an engine that is apart, you need to bag the engine! Dust and grinding junk float into the oddest places, your new engine being one of them. Keep the shop as clean as you can, shop vac the floor and benches if you can before and during the assembly. I dont like a broom, it creates too much airborn crud.

Bag it man!

If your getting bored or tired of looking at this thing, set it down, walk away. Go create a fun project....like I did. I decided to restore the engine stand! Now look at it. It looks like a brand new engine stand, and its now painted Dupli-color Engine Paint Plum Purple to match all my engines!

OK, now we need to check the deck height on the 4 corners of the block. I used a Sterrett depth guage that is made just for doing these types of things, you may have improvise or buy a guage for this. I found my deck heights to be at .026, .026, .027, and .031. I istructed the machine shop to cut the block .026 so that should put all 4 pistons at deck height, Im betting that the .031 is due to core shift and once the decking squares the block we will be setting even with a zero deck height. Doing this will allow us a good and proper quench as the piston comes to top dead center, this will reduce the chances of pre-ignition/detonation.

Also I polished the chambers on the heads and radiused all edges of the chambers, this will further help reduce the dreaded detonation. My assemble with this 3.75" stroke and 4.030 bore will be 8.77:1 with the Keith Black pistons and the Fel-Pro gaskets.

Dont forget to write all of this down and give a copy of it to your machine shop when you return the block and all for final work including decking, ballancing, freeze plugs.....the rest of the cam bearings...etc..etc...

Rotate the crank around on each of the 4 corner pistons and use your depth guage to find TDC. Once your there you need to check all 4. I like to check them over the pin, the piston will rock in the bore so if your checking the deck height on the piston at the block outside and inside side you will notice you can rock the piston. If this is your method, make sure you rock it one way and read the guage, then rock the other way and read it there again. Average the reading. Hint, if you do this method, your average will be within 1-2 thousandths of the reading you get directly by reading off of the piston pin aligned portion of the piston. This is quicker and in my opinion its more accurate. Write it all down!

We have done our job, now we can take it aprat again, pack it all up and return to the machine shop to let them perform the rest of thier job. This is going great, we feel good about our engine, we are confidant that things are fitting right, and while it was here and apart I even checked on the machine shops work and measured the pistons and bores. The bores are 4.029" and the skirts on the KB pistons are 4.0275 - 4.028. The tops of the pistons at the top ring land are tapered to 4.003. Everything feels nice. Time to lug the pile of parts back to the shop!

A very clean operation, Good Job! I might suggest a couple more steps. ! Check your clearances on every main and every rod after they all have been properly torqued.2 Check your deck height on every piston making sure you rock the piston back and forth to determine exact t.d.c. 3. Not all bearings,rods,or pistons are exact,You may have to swap some pistons around to help your averages. Go back to step 2. Check your deck height as close to the center of the piston as possible.4. Very important,If You are going to take that much care in building your motor and spending the kind of money you are spending,Do yourself a favor. Spend and extra $100.00 and buy a good true roller timing set,so when you degree your cam it will stay degreed.So many want to short cut here,Makes no sense. ENJOY!

After the block is decked and the last head (I am in the garage porting/polishing it today) is dropped off and finished, I will bring the engine back here and re-assemble it with rings. THe short block will be on its way together for real, the heads will be put on and snugged and we will learn my way of testing for piston to valve clearance as taught to me by a 30 year vetern race engine builder. Its a quick and easy way to test. After that, if all is well, its time to mask things off and finish whatever painting needs done. The colors are going to be Plum Purple on the block/timing cover/valve covers and all bolts sprayed alluminum, and the intake/heads sprayed alluminum. It will be a very bright and colorfull engine for at least a week after it gets slammed into my Father-in-laws work truck....lol...he will beat the bee-jee-zus out this thing and never think twice!

OK, to list some more numbers, Rings are Speed Pro R-8902-30 for .030" over bore.
Pistons are Kieth Black 131-030
Rod bearings are Cleavite CB663P
Mains are MS909P
Cam bearings are CH8
Brass Plugs are 97-100B
All of the above is priced at $350

Crank is an Eagle 10352320 priced at $144

Rods are Eagle SIR 5700BPLW Priced at $200

Dampner is a Pioneer DA400 at $50
Flexplate is a Pioneer 6005562 at $50

Machine shop costs are:
Degrease block, R&R cam bearings/Freeze Plugs/Galley plugs is $85
Magnaflux block is $55
Bore and finish hone $125
Line Bore $40
0 Deck Block 105
Hang 8 pistons$28
Ballance assembly $200
Extra wash/verify clearances on bearings from customer $25
Valve Job, Replace Ex guides, mill heads,install hard Exhaust seats, cut guides for P/C seals, set spring height, and crack repaire on 1 head $350
Total labor is $1013
Total Parts from machine shop is $874
Total bill from machine shop is $1887

This total is not including full Crane cam lifters $145, andCrane valve train $87.31, 16 new PEP Stainless intake $40 and Stellite Exhaust valves $77 and PEP double hardened iron valve guides $11 , oil pump $19, timing set $42, roller rockers $259, porting kit $40, and complete fel-pro gasket set $106

This has me at $2713 plus I just ordered a set of new Fel-Pro head gaskets because I appearantly messed up on the deck height and had the block cut so that the pistons were .009 out the bore.

I ordered a set of 0.051 compressed thickness Fel Pro gaskets part number FPP-1044 at Summit Racing for $49.95 each and a second set of valve cover gaskets to space the covers higher off of the rockers. This will put me at about $2850 if you include the spray paint.

This does not include about 20 hours of porting/polishing and weeks of evenings spent detailing and painting every nut/bolt/bracket/part that is exposed.

If you were to buy an engine like this, I would assume the cost to be about $5000 from a performance shop.

Im at work now so I dont have the clearance sheet here, but I know the piston are at 0.0015 to the wall, and I cant remember the others.

The application of this engine is as an industrial truck engine in a 1988 Chevy C-30 box truck. It has a Chevy pickup-truck front section with a straight frame that has a 16' box on it with an attic over the roof of the cab. This is a truck used to move estates, so it is loaded with all full furniture and packed top to floor and wall to wall. I would not be shocked to see this truck at any given time to be loaded to 10-14 thousand pounds.

This engine is not designed as a RPM engine, rather it is designed as a long life, high TQ, durability and industrial type engine. I will assume the max operating RPM will be about 4000-4500 with a 3200 cruise RPM.

The engine could be done with the same parts aside from the heads and cam if you wanted a power/RPM engine. Do the same porting as I did on the 193 heads but use a good head and cam it for performance and dump the TBI/computer crap and you could easily have made this into a 6500 RPM 450 HP 383.

I have learned from the BBF world that the cylinder heads set the limit on what power can be made, period. I started with low RPM trash heads and as I was told once ....maybe by techinspector ..... If you polish crap, you end up with with polished crap.

If you had a good set of heads and port/polished them up nice and put a nice cam that matches your compression and also up the compression over my 8.77:1 by using a less dish or a flat top piston, you could make bigger power numbers very easily.

I find in the world of BBF that any goofball can slap a 460 together with stock heads/crank/rods and good pistons/cam/intake/carb and make 500-550 HP for about 2-3 grand, and any goofball can make a 460 with home ported smog heads and make 600 HP without trying to hard and only spend about 3 grand, any goofball with the money to get good aftermarket heads can make 800-850 HP with a random mix of quality parts and 6-8 grand, and a pro can squeeze 900-950 out of a 460 for about 12 grand

OK, just for shnits and grins I ran this engine with a set of Chevy 462 casting heads and a 750 CFM carb on a dual plane intake with 10.5:1 CR, I added headers and free flowing exhaust and swapped the mild compucam 2040 to a radical solid roller. Same block, stroke, bore. Just added the ability to flow more air by way of heads and added a cam that can get down and dirty with the valve motion and lobe lift rates.

Solid rollers are by far my most beloved camshaft, the only downfall is initial cost as well as long term reliability for a daily driven street engine.

For a street engine I personaly would use a hyd roller every time. This engine is a gift, not mine, so I cut that corner of going to a roller.

OK, anyways, I added the common and old non TBI standard head and changed cam. Imagine if I added an aftermarket head that is max ported.....big power.

Here are the results of my stupid human test, I got this:

RPM HP TQ
2000 163 427
2500 214 450
3000 262 458 <--- A 3000 RPM convertor would plant you hard!
3500 311 467
4000 356 467 <---- Notice TQ peak here
4500 394 460
5000 421 442
5500 426 406 <---- Notice HP peaks here
6000 420 367 <---- Notice HP turned down here
6500 396 320
7000 363 273
7500 329 230 <---- Notice its fallen on its face here, this is not the most aggresive cam. I picked thru and found a conservative solid roller that could serve for street use as well as track duty if a good rocker like a Jesel shaft system or at least a Crane Pro Series roller rocker. THis would be about as radical of a street roller as I would go. But power is there, and its as simple as bolting together the parts. The additional cost is in the solid roller lifters (about $450) adn the pistons that should be made to order (Venolia makes a nice custom pistom for about $900). The Jesel shaft system is about $900 and about $300 to get it installed on the heads. Now, add a better head and make more power!

Cam specs are:
Part Number: 118741 Grind Number: R-248/420-2S2-6
Engine Identification:
Start Yr. End Yr. Make Cyl Description
1957 1987 CHEVROLET 8 PERFORMANCE USAGE, BRACKET RACING, GOOD MID-RANGE TORQUE AND HP, HEAVY, PRO, ETC., AUTO TRANS W/RACE CONVERTER, 11.0 TO 12.5 COMP. RATIO ADV. BASIC RPM 3800-7200
Engine Size Configuration
262-400 C.I. V

Valve Setting: Intake .020 Exhaust .020 HOT

Lift: Intake @Cam 420 @Valve 630
All Lifts are based on zero lash and theoretical rocker arm ratios.
Exhaust @ Cam 420 @Valve 630

Rocker Arm Ratio 1.50

Cam Timing: TAPPET @.0205
Lift: Opens Closes ADV Duration
Intake 36.0 BTDC 64.0 ABDC 280 °
Exhaust 72.0 BBDC 36.0 ATDC 288 °

Spring Requirements:
Part Number 99885
Loads Closed 223 LBS @ 1.950 or 1 61/64
Open 576 LBS @ 1.370
Recommended RPM range with matching components
Minimum RPM 3800
Maximum RPM 7200
Valve Float 8200

Cam Timing: TAPPET @.050
Lift: Opens Closes Max Lift Duration
Intake 21.0 BTDC 47.0 ABDC 102 248 °
Exhaust 57.0 BBDC 19.0 ATDC 110 256 °

I recomend you weld the oil pump pickup tube to the new oil pump. This is cheap insurance against a terrible failure later. If your like me, the pickup was tight in the old pump, but went pretty loose into the new one. It may fall out later and cause failure of the entire engine, weld it.