Bearing clearances and crank polishing

arknotts

formerly ark86
Jan 9, 2008
461
1
0
Ohio
I've measured all of my journal diameters on the crank and have the following:

Mains
1 - 2.3624
2 - 2.3623
3 - 2.3621
4 - 2.3621
5 - 2.3623
6 - 2.3621
7 - 2.3621

Rods
1 - 2.0467
2 - 2.0467
3 - 2.0466
4 - 2.0467
5 - 2.0468
6 - 2.0468

Great! All within spec, but I'm planning on getting my crank polished and am a little worried about the mains with a 2.3621 diameter. Toyota spec is 2.3620 minimum and I'm afraid that polishing may take off too much and go below spec. I'm trying to avoid grinding the journals down and using undersized bearings since I've read that the crank is hardened and you will lose some of that when grinding too much. Will I be safe ordering standard size bearings? I'm thinking about running on the high side of the spec anyway, giving it about .002" clearance which might work out with my situation...I'll be looking at 500-600+ rwhp on this build (http://www.supramania.com/forums/showthread.php?98230-Bearing-clearances-vs-oil-viscosity). Any input on this? I'm planning on running this by my machinist as well (obviously), but I wanted to get some of your guys' opinions on this too since I know the 7M can be a very picky beast :p.
 

arknotts

formerly ark86
Jan 9, 2008
461
1
0
Ohio
Do Toyota bearings hold up to the stresses of 600+ whp? I've heard they are good, but I don't see many people using them as examples (doesn't necessarily mean anything though).

My block is getting checked and (probably) align bored/honed since I'm changing to ARP studs for the main caps. I have new aftermarket rods as well, so I'd have to start "from scratch" with the Toyota select fit bearings, no? I'm thinking it would be easier at this point to have them do a align bore/hone, get a standard size set of Clevite's and have them clearanced to about 20 thousandths (shouldn't have to take much material off the journals much at all). Same thing for rods. If I were doing a regular rebuild with Toyota fasteners and the same rods I'm thinking Toyota bearings would make it easier, but how about in my situation? Thanks!