[trmnatr]

Originally Posted by Robert Swartz

I acquired an "010" block from a local circle track racer that had quit. The block hasn't been bored or worked on, other than the main caps are missing. My question, what's the policy on replacement main caps in stock, both NHRA and IHRA? As long as it's the same material, weight, appearence as OEM. Is there anything I need to look out for.

Does the block say 010 with an 020 under it behind the timing cover? Is it a 4 bolt main block?

You have a couple options,,,
Option 1) Purchase the 3 center main caps and find a front and rear cap off another block, they came from the Factory with Nodular "2482" caps (see link below)

Remember, it will need to be line bore and honed. My opinion is, if the caps are not Nodular, run ARP Bolts or Milodon Main Studs. If the caps are Nodular, You can run ARP Main Studs or anything else you wish to.

Here is the link for the "2482" Nodular caps that came on many 010/020 4 bolt main blocks
http://www.gmpartsdirect.com/perform...CATID=660.html

Option 2) Order Milodon 11160 cap kit. This comes with three Ductile caps with much THICKER cross sections than Factory caps. This kit uses a 350 4 bolt register width with 3/8" angled outer main bolts. This kit comes with the outer splayed bolts with washers and the 7/16" main bolts with washers. The 7/16" main bolts even have a good amount of additional thread engagement than stock main bolts.

If you wish to use studs, use Milodon part number 81128, this stud kit is for their caps only as their caps have much thicker cross sections.

Then I would also use the Milodon 2 bolt front cap, part number 11153. I will link them on Jeg's so you get an idea what they cost.

Milodon 11160 cap kit, $229.99
http://www.jegs.com/i/Milodon/697/11160/10002/-1

Milodon 81128 stud kit, $66.99
http://www.jegs.com/i/Milodon/697/81128/10002/-1

Milodon 11153 front cap, $81.99
http://www.jegs.com/i/Milodon/697/11153/10002/-1

Here are some of my suggestions if using this for a race block.
1) Get the block checked and sonic test cylinder walls
2) Clean/Tank block
3) Install main caps, get the caps on and torqued, line bored but do not do final line hone yet
4) Fill the water jackets with Hardblok before being bored and with main caps torqued (after line bore but before line hone). If any of the outer splayed bolts "Broke Through" in too the water jacket, remove them and dip the end of it in wheel bearing grease and install before putting Hardblok in. This will stop Hardblok from sticking to the end of the bolt for easy removal
5) After doing both sides with Hardblok, now its time to have the engine line honed. The reason it should be done here, is because the Hardblok makes the bottom shift a little and your main line will be PERFECT if line honed after the Hardblok is set up.
6) Now go on too boring and honing the engine to the desired specs

Here are some mods I would do if I were you,,,
1) on the center 3 mains, drill the oil hole from the cam bearing to the main saddle to 5/16" for increased oil flow.

2) drill a .063" to .125" hole (depending how much oil you want here) at about 11:45 clocking, through the thrust face of the block so it runs into the annular groove under the front cam bearing

3) take an old oil pump and cut the neck off, bolt it to the rear cap, look through it, you will see the rear cap needs additional porting in most cases so all your oil from the oil pump can go into the passage, I have seen this 50% blocked from tolerances. Don't go too far or you will create a large oil leak which will lower pressure and volume of oil

4) i use dura bond cam bearings, which are coated by Calico. Depending on how much oil I want, I will drill the oil holes out to be 1-3 steps larger. I also clock them with 1 oil hole around 2:00 to 4:00 and the other around 9:00 to 12:00 so spring pressure and RPM will not cut off oil flow.

5) i open both rear drain backs no smaller than 1/2", The drivers side i open up much larger. Then I install the heads with gaskets and port through the oil return holes in the heads going to the block for rapid oil return

6) you have to take your main bearings and install them after you clearances are correct, then remove the caps and using a small carbide bit, grind the oil hole in the center 3 main bearings to be perfect to the main feed hole, also match the front and rear main bearings too as these are usually off also

7) take your main bearings out to modify after marking which one is which, now you want to narrow the main bearings. this will cut down on friction more than most would think. If you want, you can do this with the rod bearings too

8) I don't do machine work (I do mods to parts, but no boring etc etc), I always use my hones to put a finish on the cylinders that I have used to go faster when I tested it. Here is what I do,,,
After the machine shop hones my block for desired PW clearance, I wash the block out and take a flex hone (320 grit) and hone the cylinders really good. The key here is to have the cordless drill on high before it goes in the cylinder, this allows the end of the beads to wear and not the sides, which also gives you a better finish

Use the 320 grit hone, flooding the cylinder with WD40 then do 6 quick fast strokes. Do this to all cylinders. Then use a Plateau Brush for 3 slow strokes flooding the cylinder with WD40 then do 12 quick strokes. Link below has a picture of the brush we use
http://www.cylinderheadsupply.com/44plbr.html

Using this method, your torque to turn over the rotating assembly is minimal and it seals up very well.

9) take an old chimney cleaning brush (stainless steel) and polish the rifle line, fits in there perfect. assume you could use a flex hone but i know this works great for us

10) if your using say a 1/16" ring pack or 5/64" ring pack and a .040" quench, you can get better sealing by running the piston .025" out of the hole and using a .065" gasket. This still leaves you with a .040" quench but there is now the piston sticking out of the bore helping to guide cylinder pressure to the rings lateral gas ports in the spacers, rings, or pistons. Have seen 400 engines with 0 deck and .040" quench run good, but with .065" gasket and .025" out of the hole they run even better

Hope this helps