[cobalt327]

I'm a little surprised there's no date back by the distributor. In any event, you know basically all you need to know to order parts for it. It's a '87-newer 1-piece rear main seal block, prolly w/o the bosses for a roller cam, so that makes it the same as the TBI truck engines of that era. Except for the rear main seal/pan gasket, it's basically the same as any 350 from '68 onward.

Some possible differences between your block and the earlier type (may not be all of them):
• You might have powdered metal rods (but I doubt it).
• The flexplate/flywheel has a counterweight to compensate for the loss of the small counterweight that the 2-piece rear seal cranks have.
• The crankshaft rear flange bolt pattern is smaller. This prevents the earlier (~'86-back) neutral balance flexplates or flywheels from being used.
• The fuel pump boss may or may not be machined for a mechanical pump to be used. In your case it probably is machined all the way.

In addition, up to 1985 the oil ring/piston groove was 'deep' (0.195" or thereabouts). From about 1986 to the end of the L31 Vortec production, the 'shallow' rings (around 0.165") were used- but there could still be deep groove pistons and rings being used from about '95-back.

And if that wasn't enough, there were metric rings (2mm x 1.5mm x 4mm) used from about 1992 to 2002 when the Vortec L31 engine bowed out. If you had access to the vehicle VIN, the metric ring engine (might be others) is VIN P.

[31ROC]

Thanks for all that info!
This motor was "built" when I purchased car, somewhere I have the specs on evrything done to it, heads,cam, lifters, p-rods, pistons etc....so that part of it I'm not worried about.
So looks like a possible '89 truck block. When I disgard this 700R4, I should learn more about those items you listed at the flex plate, thanks.

[31ROC]

I'm baaaack.....been ordering parts.
Purchased Ram clutch, and Ram hydraulic throw/out brg, and Ram steel flywheel.....never owned a hydraulic clutch set-up, which brings up next set of questions for you pros out there....
Am I going to need to shim this T/O bearing, or does it go right onto the Muncie M20 as is?
I have not found a bellhousing yet, but will that determine shims or not?
When I purchased the master/cylinder for the clutch, it came with a slave cylinder, but I was reading that I dont need a slave cylinder?
Thanks as usual for all advice.....

[cobalt327]

Originally Posted by 31ROC

I'm baaaack.....been ordering parts.
Purchased Ram clutch, and Ram hydraulic throw/out brg, and Ram steel flywheel.....never owned a hydraulic clutch set-up, which brings up next set of questions for you pros out there....
Am I going to need to shim this T/O bearing, or does it go right onto the Muncie M20 as is?
I have not found a bellhousing yet, but will that determine shims or not?
When I purchased the master/cylinder for the clutch, it came with a slave cylinder, but I was reading that I dont need a slave cylinder?
Thanks as usual for all advice.....

The bearing should be threaded for adjustment, follow the instructions for air gap between it and the pressure plate, and I'd recommend using the high side clearance if there's a range.

You need no slave, the HTOB is the slave, so to speak.

[31ROC]

Thanks again!
So does the bellhousing type/brand matter?

[31ROC]

Got a DEAL on Lakewood Bellhousing...now I need to know what size/type of bolts for bellhousing-to-block? OH, also, what bolts should I be using for flywheel and clutch set?
Thanks

[cobalt327]

Originally Posted by 31ROC

Got a DEAL on Lakewood Bellhousing...now I need to know what size/type of bolts for bellhousing-to-block? OH, also, what bolts should I be using for flywheel and clutch set?
Thanks

Bolt size for bellhousing to block is 3/8-16, length as required for the bell you have.

Same thread for the pressure plate, but a 1" under head length, and not threaded all the way to the head. Use hardened flat washers and a dab of loctite. You could use a set of ARP or similar bolts for the flywheel to crank and pressure plate to flywheel if you don't have the original hardware in good shape.

[31ROC]

Originally Posted by cobalt327

Bolt size for bellhousing to block is 3/8-16, length as required for the bell you have.

Same thread for the pressure plate, but a 1" under head length, and not threaded all the way to the head. Use hardened flat washers and a dab of loctite. You could use a set of ARP or similar bolts for the flywheel to crank and pressure plate to flywheel if you don't have the original hardware in good shape.

THANKS!
Am I using flat washers everywhere?

[cobalt327]

Originally Posted by 31ROC

THANKS!
Am I using flat washers everywhere?

Yes, all these are flat washers. You can use regular (non hardened) washers for the bellhousing, hardened washers for the PP. I don't use loctite on the bellhousing bolts, but no harm if you do.

Torque: I'm seeing 25 ft/lb bellhousing, 35 ft/lb PP and 65 ft/lb flywheel to crank. That's from Summit, I don't have a factory manual handy.

[31ROC]

Originally Posted by cobalt327

Yes, all these are flat washers. You can use regular (non hardened) washers for the bellhousing, hardened washers for the PP. I don't use loctite on the bellhousing bolts, but no harm if you do.

Torque: I'm seeing 25 ft/lb bellhousing, 35 ft/lb PP and 65 ft/lb flywheel to crank. That's from Summit, I don't have a factory manual handy.

Excellent info, and much appreciated again!

[techinspector1]

Use caution when selecting fasteners. There is a lot of offshore crap out there. Actually, I'd go to the local Chevy dealer parts department or the local Caterpillar dealer (Grade 8 hardware) and purchase all the fasteners for the bellhousing and clutch. Avoid any thoughts about chromed or stainless hardware.

I have been unable to find any really good stainless bolts, seems like they are all soft, low-quality parts. Chromed parts, unless they have been baked post-plating, will have free hydrogen atoms in their makeup. These atoms act like little chisels and can break or crack a fastener, even if it is under NO load, and since you have no idea if the fasteners were baked or not, sidestep chromed hardware or any hardware that has been electrolytically plated. Read up on "hydrogen embrittlement" if you want to add to your knowledge.

Here's a quick chart showing "hash marks" and corresponding strengths....
http://www.boltdepot.com/fastener-in...ade-Chart.aspx

As far as a scattershield is concerned, please read through this thread.....
scatter sheild

[31ROC]

Originally Posted by techinspector1

Use caution when selecting fasteners. There is a lot of offshore crap out there. Actually, I'd go to the local Chevy dealer parts department or the local Caterpillar dealer (Grade 8 hardware) and purchase all the fasteners for the bellhousing and clutch. Avoid any thoughts about chromed or stainless hardware.

I have been unable to find any really good stainless bolts, seems like they are all soft, low-quality parts. Chromed parts, unless they have been baked post-plating, will have free hydrogen atoms in their makeup. These atoms act like little chisels and can break or crack a fastener, even if it is under NO load, and since you have no idea if the fasteners were baked or not, sidestep chromed hardware or any hardware that has been electrolytically plated. Read up on "hydrogen embrittlement" if you want to add to your knowledge.

Here's a quick chart showing "hash marks" and corresponding strengths....
Bolt Depot - Bolt Grade Markings and Strength Chart

As far as a scattershield is concerned, please read through this thread.....
scatter sheild

Already ordered ALL ARP fasteners for everything! Regarding the safety bell, already read that thread....
Thanks!