I am putting Chevy 2.100 rods to Y-block and machinist wants to know the tolerance for big end radius.

I want also know big end width and small end gap.



Thank you.





Hyvinkää, FI

2.1" +-0.001 or what?


Hyvinkää, FI

I grind std. chebbie rod throws to 2.099" maybe 2.098" for racing. side clearance should be .004" but more is OK.  This is how I cut the rods down.

 

Cut equal amounts off each side to a width of .850 and run CB663HD rod bearings.

   God Bless.   Tim                           http://yblockguy.com/

350ci Y-Block FED "Elwood", 301ci Y-Block Unibody LSR "Jake", 312ci Y-Block '58 F-100, 338ci Y-Block powered Model A Tudor

tim@yblockguy.com  Visalia, California    Just west of the Sequoias

What kind of rod are exactly using in your engines? You will put it on a 292?

Thanks for your anwers!

If you have a crank offset ground check the bearing to radius clearance very carefully. Make sure that the bearing doesn't pinch the radius on the crankshaft. This will trap oil in the bearing and burn up the bearing, and / or the crankshaft.

A safe number for bearing clearance is .001" per 1" of diameter. 2.100" journal=.0021" clearance ect.

I like to see .014 to .018" side clearance between the rods. The only oil that lubricates the camshaft is what is thrown off the crank and rods. Y-Blocks had .012 to .016" from the factory.

As for wrist pins .0004" seems too tight for any performance use and not much reason to go over .0008" so we try to hit .0006-.0007". Some aftermarket rods are .0008" off the shelf so you just have to live with it. Over .0010" is okay for drag race/circle track but too loose for street, IMO 

http://ford-y-block.com 

20 miles east of San Diego, 20 miles north of Mexico

For what its worth, I've got 2 stroker motors with whole assembly's from John. They run very well. He also has a spec to the turn the fillet (?) if you are offset grinding the crank. Mine are about 320 and 340 with (I think) 2.1 and 2.0 bearings. Don't trust the memory so much any more.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

For what it`s worth this is what I did. My std. 292 crank, I offset ground it to a 3.48 in. stroke. I then used a set off $250 Eagle SIR Ibeam rods that I gound .010 off the inside and .060 off the outside to narrow them from .940 to .870 and center the beams. For bearings, I used King rod  bearings, CR867HP std. These allow a 2.10 rod to be used with a 2.00 crankpin. The chamfer on the bearing worked perfectly  with the crank throw. It  was like these parts were made for the "Y". Just my 2 cents worth.

Greg Dietrich Mt.Morris Il

Greg, am I to understand the King rod bearing has a thicker section allowing you to use the rods normally configured for a 2.1 crank pin on the 2.0 journal? Is there an advantage to this?

Yblockpinto312 I sent you a private message.  Wondering if you can give any more info on your stroking mods?

Thanks

Don, there are limited choices in rods with 2.00 journal. A lot of the less expensive rods are only available up to 6.00" in 2.00" journal.

With the 2.100 rods 6.125  6.200 and 6.250 are available in a wide price range.

We use 6.200" rods with a combo like Greg's and that requires an H-Beam with 2.00" journal rods. The H-Beams are considerably more expensive.

http://ford-y-block.com 

20 miles east of San Diego, 20 miles north of Mexico