main bearing clearances~are these ok?

[bb71challenger]

I used some plastigauge on the mains today and got .003 on #1 and #5 and .0025 for #2, #3 and #4. When I got done and torqued everything down it spins nice and freely. I am just wondering what would cause those outside mains to be a different clearance.

[Chryco Psycho]

I would shoot for .002 for a street engine , .003 is ok for higher rpm ,you may have trouble getting decent oil pressure with a std oil pump , was the block line bored ?

[bb71challenger]

The machinist said it was true as it came from the factory. Could it be the 440 source crank? I remember something about .003 being a good thing but maybe that was a drag engine. would a high volume or high pressure oil pump make things better? The guy actually told me that a standard oil pump would be fine especially since I was going to run a solid lift cam.

[72cudamaan]

Could be the crank. Did the machinist measure it? Did he measure the main bores with ? without the bearings?
You may not have any issues with a .ooo5  variation. I like .0025 clearance myself. What kind of bearings are you using?

[bb71challenger]

although the bolts were slightly wet they did not give like they should have and I did not wet them until I bolted the crank down. I think since I am barely into this I am going to pull it back down and make sure its all hunky dory. I am going to chase the threads to make sure they are clean and do it again. I think the bearings are Federal Mogul but I would have to look to make sure.

[bb71challenger]

main bearings are engine pro?

[high perf mopar]

I used some plastigauge on the mains today and got .003 on #1 and #5 and .0025 for #2, #3 and #4. When I got done and torqued everything down it spins nice and freely. I am just wondering what would cause those outside mains to be a different clearance.

nothing is precice across the journals unless its a nascar or nhra motor where thousands have been spent in machine shop hours to get it dead balls on..   2 1/2-3 thousands is acceptable for street/strip use,,my clearances r 3-3 1/2 mains and rods,,,did not want to grind the crank and take a chance on the outside crank grinder...oil pressure was 100+ with a high volume pump,,had to install a milodon adj oil pressure reg to turn it down,,using 20-50 oil...

i would call that racing clerance! u dont want a tight motor,,u should be fine.
 

[Chryco Psycho]

I generally use Michigan / Clevite 77 brgs . I would not use a high volume pump with a stock pan std volume with high pressure is fine

[bb71challenger]

The 440source crank requires radiused bearings if I remember right so that might explain the off brand bearings. I am going to check end play while I have it tightened down.

[high perf mopar]

this is why i let my machine shop determine what bearings i use per my requirements of clevit 77 full/3/4 grooved main bearings,witchever r ava for my app.mic them.fillet and non-fillet journals will require diff bearings,,and u dont have to try and use plastigauge to determine bearing clearnaces,,only use plastigauge if u have to...a couple xtra $$ at the shop to mic, but u will know exactly what u have..

when i got the motor back from the machine shop it was painting by the numbers,,bearing box 1 goes to journal number 1,,and so on..$$ well spent,,anybody can assembly an engine,,but we r NOT machineist's.....OH,,no dry threads!!!!use ARP lube on ARP bolts or,,oil on non ARP bolts..never dry!!!ANYWHERE!!!