Hi Mike,
Shoulda just had you build this big block. That way all my problems would be yours smile.gif

I just measured the crank and mains.

The crank is a 4.25 Dragonslayer.

The main journals miced 2.7479/2.7480 on 1-4 and 2.7476 on the rear cap.

The bearing installed came out at 2.7520/2.7519 1-4 and 2.7527 on the rear.

That comes out to .004 clearance on 1-4 and .0051 on the rear.

According to what data I have the crank is about .001 on the small side which appears to be the issue.

The bearings are King.

I assume .004 is too much.

What are your thoughts? I was going to take the crank to the machine shop and double check my measurements on the crank, but I am pretty comfortable with them.

Is it common to need .001 over bearings on new stuff?

With the same mic, the rod journals came up 2.1990/2.1992 which I show closer to nominal.


Any thoughts? Or anyone else?

Every part on this engine has needed something done to it...

Originally posted by Doug F.:
Hi Mike,
Shoulda just had you build this big block. That way all my problems would be yours smile.gif

I just measured the crank and mains.

The crank is a 4.25 Dragonslayer.

The main journals miced 2.7479/2.7480 on 1-4 and 2.7476 on the rear cap.

The bearing installed came out at 2.7520/2.7519 1-4 and 2.7527 on the rear.

That comes out to .004 clearance on 1-4 and .0051 on the rear.

According to what data I have the crank is about .001 on the small side which appears to be the issue.

The bearings are King.

I assume .004 is too much.

What are your thoughts? I was going to take the crank to the machine shop and double check my measurements on the crank, but I am pretty comfortable with them.

Is it common to need .001 over bearings on new stuff?

With the same mic, the rod journals came up 2.1990/2.1992 which I show closer to nominal.


Any thoughts? Or anyone else?

Every part on this engine has needed something done to it... =
Hi Doug,
Are we having fun yet ;)
It is not that unusual. in fact I routinely use .001's especially on the mains.
This should get you down to an "acceptable" level of .003 but I would prefer them at .0022-.0027.
I have put a lot of rats together at .003 but prefer not to run this much clearance.
The actual clearance numbers according to Clevite are .0007 to .0037.

Doug,

I also had to go .001 over on my mains to get them to .0025" on 1-4 and .003" on the thrust. This was with a Callies Racemaster crank, so not a cheapo deal.

Jody

Thanks guys.

Mike,
Quick recommendation on a good chamfered BBC std +.001 bearing. I guess that would be the Clevite "H" series?

That thrust has me worried a bit since it checked at .005. Are there any .0015 bearings or just a .001.

I know it is no big deal, but I am setting a record on the slowest engine build here...

Just got done doing "CNC" chamber work on the bridgeport on the heads.

Thanks Jody.

Yes, the Clevite H-1's.
They don't have .0015 or .002 but Jody bought coated ones from Callies & it closed the clearance up another .001 if I recall correctly.

Doug, I just went through all that with my 555 with Dragonslayer 4.25" crank...took about 2 weeks between measuring and buying bearings to come up with what I wanted... smile.gif

I purchased 1 set of std King bearings, 1 set of std Clevite bearings, 1 set of Clevite X bearings, and 1 set of callico coated std, and X bearings to come out with my desired .0027 clearance on the mains....

The King bearings are thiner than the Clevite bearings....I was getting about .0040 clearance with them, and about .0034 with the Clevites.

If I remember well (I would have to check my notes) I ended up with half standard and half X bearings both Callico coated....I think the -0.001 would give me .0022 clearnace and then I went with the .0005 thiner to get the .0027 that I wanted...

Also, even though your method is more than likely accurate, I would strongly recommend you use a dial bore gauge and measure the clearance directly on the mains with the bearings installed...I purchased one before I started building my engine, but I think you can rent them as well...

Good luck.

Thanks guys.

I am using a 2 point dial bore gauge on the main bearings installed.

Before I get to it, how did the rod bearing clearances go Yanniz? Where did you buy the coated bearings from? How much $?


Guess I am used to using stock parts, they don't need 9 sets of bearings to get it right.. smile.gif

The first thing you question is your measuring equipment. Once again they unfortunately seem pretty good :(

Thanks again, it is great to get the feedback.

Doug,
does your bore gauge go out to .0001 or .0005? For accurate measurements you would want the .0001 increment gauge...

On the rod bearings I had to stay with non-coated Clevite bearings to get my clearance where I wanted it...it would depend on your rods and sizes, so you know how it goes...measure, measure, and measure... smile.gif

I bought my coated bearings directly from Callico...little over $100 if I remember well...

my mains on the crank were at 2.7484 and rods 2.1997..

also, Summit sells single bearings...you might want to purchase one of each side that you think you will need and try that route..

good luck...it is a slow process but at the end it is very rewarding knowing that you have done the work yourself and also knowing exactly what is going on inside your engine re clearances, how things are put together et cetera....I had mine dynoed a couple of weeks ago and I had my fingers crossed on runs 1-10...fully enjoyed runs 11-17... smile.gif

I think even lower dollar bore gauges work fine for this as long as you are measuring both the crank journal with the same measuring tool. You're only measuring differences. What you don't want to do is use a machine shops crank measurement and then your own dial bore gauge to measure the installed bearing size and subtract to get your clearance; I know you're not doing this Doug, this was just for others wanting to check their own clearances and not wanting to spend hundreds or thousands of dollars on measuring equipment.

The coated bearings I used were from Callies. I believe they were a Clevite H bearing set. The coating added app. .0008-.0009" as I remember which got me where I wanted to be.

Jody

Jody, you are right...what I have found out is best to eliminate the math out of all this...

dial boar gauges are comperitive instruments...they will give you the difference in size from a pre-set measurement..

This is how I did it and eliminates all errors...

measure your main journal on the crank with a good mic...then lock the mic, and set the bore gauge to measure across it and ZERO it at that point...

Once you do that, then measuring your bearings with the bore gauge, the gauge will show you what the clearance is directly on its dial....no math involved...

Doug, a couple of more things that I should have mentioned even though you might be aware of...

make sure that you rock the bore gauge once you set it at your measuring point until you get the shortest distance across...even a slight tilt on the gauge it can show you off by a few...

Also, when you are making clearance measurements, make sure that you have the cars tighten down exactly to the torque spec and using the exact lube as your final assembly...mine was 76 ft-lbs with ARP bolts and ARP moly lube...

And lastly, you will be amazed how much difference it makes on your rear/thrust main having the oil pump installed and tightened down....If I remember well is to the effect of .0005 or so..!!!

Keep us posted...

One more thing...I think Callies uses Callico bearings...not sure...
Callico says that they add anywhere from .0003-.0006 and they were right on with mine....I think with non-coated I was at about .0031/2 clearance and I ended up at .0027 with the coated bearings....

Doug,
Just a suggestion but I would keep this simple & stick with the Clevite bearings.
I do not use King bearings as both I & a few other performance shops have had problems with them coming apart.
Seems like the top layer "delaminates" itself or something.
This may have been addressed but I ain't interested in finding out :D
You also don't want the 1X bearings, they give you more clearance not less.
I also like the Fed Mog performance bearings but don't use them hardly at all as I have never had a problem with Clevite,,,, you know, if it ain't broke,, don't fix it ;)
There all no problems at all with mixing std &
-1's to arrive at your desired clearance.
And again, .002-.003 will work just fine but my prefered numbers are .0022-.0027 ;)

Thanks guys.

I do have a .0001 bore gauge, but will set it up like you say Yanniz, did it a little different. I zero the bore gauge with the same mic, but don't lock out the mike like you say.

I had the mains align honed with the pump (or they said they did anyhow smile.gif ) I didn't put the pump on when checking but will to get final results.

Gonna call Callies up and ask what bearings will be right without having to buy more. Hopefully they have an idea..

Mike,
ONE more question (that's a lie!). If I just get the .001 Clevite H's I assume I should get into the .0025-.003 range which I think I would be happy with. Don't know why that shouldn't happen. Won't hold ya to it! smile.gif THe budget was long ago past and I'd rather stick with a set of $50 Clevites than $100 coated pieces.

Thanks again guys.

If you are at .004 now it SHOULD put you at .003 but don't count on it :D

One other thing, when you lock the mikes do it on the journal not after you take it off.
The lock can skew the setting up by an easy half thou sometimes if you do it after taking the mikes off the measured object.

Well, two more things,,, recheck the bore gauge often as it will change just from handling it.
Be nice if you are doing all this around 65-70 degrees,,, tenths are VERY SMALL ;)

Thanks Mike,
Yep, I am locking the mic on the crank.

I just checked a rod with the King bearing.

I got .0029 clearance.

I'll look into it a bit more, but I think for now I will order a set of .001 H's and a set of std. Clevite rods.

Do you like .003 on the rods or smaller? If smaller I could look into a half set of stds and .001's for the rods maybe.

You scared me on the Kings smile.gif I'll get some Clevites all around.

I asked around a little on them after the machine shop sent them and didn't see anything terrible on the internet, and it is what Lunati uses (not that that means anything to me), but I agree 110% on using what works!

I only get a few spare hours a week to work on this thing so it is going slowly!

.0022-.0025 on the rods, give or take an inch or so :D

Doug, just as another reference point. I had an opportunity to visit with the folks at Reher-Morrison for a few days and they typically set up the main/rod clearances on their Super Series BBC engines at .0035 -.0038. Granted this is on 900-1300 HP deals.

If this is a race engine, I wouldn't sweat it too bad if you are .003+.

This is the first time I've heard anything bad about King bearings, was there a bad batch of bearings made maybe? Interesting, I wonder if I should run the set I bought.

Doug,

What brand bore gauge and mic are you using? I've been looking for some that fit my budget. Most of the dial bore gauges that are reasonably priced only measure to 0.0005 . Or does that get close enough? Thanks

hey Mark, in my opinion .0005 is good enough to check machine shop work et cetera....if you are doing the work yourself on clearances et cetera you should think about the .0001 gauge....

after all there is a big difference between .0025 and .0030 clearacne.....

I bought a powehouse unit and had it checked against a more expensive one and it was as accurate...

good luck.

Yanniz,

I looked at powerhouse's website, and the only thing I see are inside mics that measure to 0.001". Which one do you have? Thanks

http://www.powerandperformancenews.com/store/merchant.mvc?Screen=CTGY&Store_Code=PH&Category_Code=MICROMETERS

Mark,

Do a search for "dial bore guage" and it should show up. Fpr some reason it doesn't show up in the index.

I have the same one as Yanni (.0001"). From what I remember it was about $300.00

p/n - POW256467

Mark,
DragRacer is correct...here is a link for it.

http://www.powerandperformancenews.com/store/merchant.mvc?Screen=PROD&Product_Code=POW256467&Category_Code=&Store_Code=PH

Thanks!