440Source Crankshaft journal diameters are spot on

Is this the norm or did I get a bad one? 440 stroker crank, 4.25" stroke, 2.7500 Mains, BB Chevy rod journal size - 2.2000"

All mains are undersized...none measure 2.750" and some are .0007 - .0008" too small
the first 3 rod journals (starting at the front) are spot on at 2.2000", the rest are all undersized...some as much as .0008"

I don't have the notebook next to me to give the exact measurements, but damn....not really what I was expecting from a brand new crankshaft.

Any similar experiences? or is this a fluke?

Mike@440Source

however, Southern California is getting very bad weather might be tough to reach.

Sounds like someone had a bad day setting up the grinder. Not a fun problem to have since there is no easy solution. You can polish then mix and match bearings, or send it out for regrind, or send it back. None of those options are great.

Doesn't sound good. Somethings are frustrating. But if it was 2.750" (stock, which would give you stock clearance, which nobody says is enough) then you would be coming on here posting "Where can I get bearings with more clearance." Mock it up and see what your clearances are. Then decide if you're upset. My guess is you aren't going to feel as bad. This isn't the 70's. We don't just put the bearings in without checking anything and slap it back together. We're measuring in tenths now. (As shown in your original post.) Juggling bearings is part of building something today.

I'd send it back...with the only alterative being that all similar journals be re-finished (polish or grind) to the same size. On top of that you didn't pay for a "blem" crank why would you accept one. Defiantly would not mix and match bearing sizes though...too easy to mess things up when the parts are correct.

If it will make you feel better, the last Callies Magnum crank I got from Ray Barton was, I believe, .0008" under on the mains and .0006" under on the rods. Yes, I wish it was standard like you do. But I assume he orders them this way so it will have bearing clearance. If the crank is standard, your clearance is going to standard, and nobody want things that tight anymore.

My Callies crank measures between 2.7491" and 2.7494" on the mains and 2.1993" and 2.1994" on the rods. Doesn't seem like 0.0007" or 0.0008" under the nominal would be out of line?? I wouldn't expect the journals to measure right on the nominal dimension.
You might have to use half of an 0.001" under or 0.001" over bearing to get the clearances where you need them. I can't remember the last time I built a motor only using one set of bearings. I have a shelf of left over half shells...

That's pretty much what mine looks like.

Send back and get a Molnar?

My Molnar crank was spot on when we built my engine. No fudging bearing sizes to get clearance. Engine builder even commented on how nice it was. Can't say that about the other budget cranks we have used over the years.

Just have to use chamfered mains.

Same!

I would much rather have them to small than a TINY bit to BIG
Next step is to install and torque the main bearings and see what the I.D. is on all five bearings, same thing on the rods, torque them up and see what the I.D. is and then do the math for oil clearances. I like .0025+ on the rods and .0030 + on the mains
I use the narrow full groove Seal Power truck main bearings and what ever brand rod bearings I have in stock that give me those rods bearing clearances I want, I have been using a lot of King brand rod bearings this past two years

Crank journals tend to vary, some more than others. The guy I work with fits bearings all the time. Sometimes he'll polish the crank to get it to the right spot, sometimes he mix and matches bearings halves to get the correct clearance. That is just how it is these days. You can send the crank back but there is no guarantee that the next one will be any better and you'll be out $200 for shipping plus a couple of weeks of shop time.

Less than .001 difference ... hardly worth losing sleep over.

Most guys can’t measure .001 let alone .0002

Thanks for all the great info, gents. It is much appreciated!

So what are you going to do.

That's like picking fly sh!t out of pepper...

X2!!!

I'm wondering if this was THE CHEAPEST crank he could buy? Recently, I measured an Ohio and it was pretty consistent FWIW. They also have a good pricepoint.

My engine uses half KING rod bearings, and half Clevites.

I'd say less than .001 difference over all journals is pretty damn consistent !!

From what I hear the crankshaft manufactures are targeting low end of the spec or even slightly below to get the clearance where most performance builders what it. Most shoot for .001" for every inch of journal diameter so in our case .0028" clearance. If the journals where at nominal diameter it would probably be way to tight of a clearance.

Same for rod journals except that chevy journal sizes have a wider selection of under and oversized bearings.

AG.

I doubt it will be an issue for what you are doing. AS stated send it back if you feel like it but no guarantee the next one wont be different or "better".

If you haven't measured your clearances you haven't found a problem.

wheres 440sourcedotcom you know they seen this what there answer ???

So, I was very wrong to be worried...and I am very impressed.
I went back over the crankshaft and re-measured everything. Made very sure I was getting the measurements using the same amount of drag across the journals with the mic...

Main Journal Measurements:

#1 - 2.7493
#2 - 2.7494
#3 - 2.7492
#4 - 2.7493
#5 - 2.7493

only .0002" variance between all journals

I set up my dial bore gauge off of each main journal measurement and came up with the following bearing clearances:

#1 - .0024
#2 - .0024
#3 - .0020
#4 - .0028
#5 - .0028

I'm going to swap the lower bearing halves for 1 and 2 with 4 and 5 and see what happens. Ran out of time tonight.

The issue is me being rusty, not the machine work.

When in doubt, measure enough times to remove all DOUBT
i like those measurements

Good for you

Yes sir! I also verified with a T-gauge and micrometer measurement...That was within .0002" of an inch of the direct measurements with the dial bore gauge...so definitely happy!

Hoping to get the mains switched around and re-checked and get the rods done tonight as well.