3rdCoastPowerSports

iTrader: (5)

stock LS1 crank (just back from polishing). I used plastigauge to measure the rod bearing clearance. i get clearances anywhere from .0015" to .0018" (keep in mind its plastigauge, not exact). I would ideally like them to be looser around .0020". can anyone with any knowledge tell me if i will be ok with these clearance. car is a 400 rwhp N/A heads and cam street car. thank you

93Z2871805

iTrader: (5)

.0009-.003 is spec. I usually like .002-.003 (my 6.0 is at .0027) I'd let it ride though (plastigauge usually reads a little tight anyways).

bww3588

iTrader: (49)

Being it's plastigauge, I would roll with it. They are probably closer to .002. If you really want to know for sure, take the crank and rods to the machine shop and have them mic'd. If they aren't busy, they will probably do it for free.

3rdCoastPowerSports

iTrader: (5)

yeah i thought plastigauge read a little tighter than it actually is, the absolute tightest i measured was .00155" (my closest estimate). so that means that its more like .0018-.0020" at the tightest spot

3rdCoastPowerSports

iTrader: (5)

if i wanted to roll with more clearance could i just take the rod caps off and switch out the rod cap shells with either .0005" or .0010" over sized bearings to get my clearances into the .0022"-.0025" (plasti measurements) range?

RezinTexas

I think our builds are on the same schedule, haha.

I just measured all my rod bearing clearances today, and I have one that is .0017-.0023. All the others are .0024-.0028.

Also interested to hear feedback on undersized bearings.

3rdCoastPowerSports

iTrader: (5)

anyone have any input about swapping out the claim shells on the rod cap for over-sized shells

streetknight2

iTrader: (10)

I put ARP rod bolts in my stock rods and they had to use the "1" over bearing cause they moved a little. I only come up with .0011 with plasti gauge. Never ran one that tight. Guess I'll have to borrow a dial bore gauge to check a little closer.

If I still come up with the same # of .0011" should I let it ride or put a halt to the build. The crank was standard and just needed a polish, no overbore, LQ9 with LS3 heads, shift RPM will be 6800-7000........100% Track car only

bww3588

iTrader: (49)

Have your rods resized and run .002 over bearings.

streetknight2

iTrader: (10)

To me bww3588?

bww3588

iTrader: (49)

Yes. Sorry I can't quote on my phone.

streetknight2

iTrader: (10)

Me either lol.

RezinTexas

My undersized rod bearings just came in, here are the results. Measured with .001mm dial bore gauge.

Eagle H-Beam Rods, ARP 8740 Bolts

Initial setup: Clevite H Bearings (CB-663HN) Upper & Lower. Min clearance = 0.0017", Max clearance = 0.0023"

New setup: Clevite HX Bearing (CB-663HXN) Upper, Clevite H Lower. Min clearance = 0.0020", Max clearance = 0.0030"