Need advise on Main and rod bearing clearance on turbo mitsu 4g63

[4g63freek]

I have my mitsubishi turbo 4g63 short block built with all the goodys. Ross,Scat,Clevite, ARP. My mains and rod beaings are at .0015- .0017 clearance after 10/10 on the crank and line hone. The factory specs ask for .0008- .0020 on both. I will be using royal purple 10/40 once the engine is broke in.
What are your thoughts on this seams tight to me???

 

[evelrod]

I use .0012 to .0015 on my race mini 1380cc bottom end and .0015+ on my JE pistons. Tight, but it works great. My Lotus 1600cc engines usually set at .001 to .0015 rod and main and .004" on the Venolia and .003" on the JE pistons. I use Mobil 1 , 15W-50 with oil temps at 190 to 210 F. No problems after a 10 hour weekend.
Sounds like your in the ballpark.

Rod

 

[MNRaptor]

We typically use .001" to .0018" on these engines with a lot of success. The only concern with what you mentioned I would have is the crank being ground. I won't run a ground Mitsu crank in a high performance app without having it re-nitrided.
We have only seen one failure over the years in an hybrid 4g64/63 7bolt motor due to a soft crank and heavy clutch. The bearing wear was even and considerably less than the wear on the thrust surface of the crank.I have yet to hear a solid answer on how much you can remove on a Mitsu crank before the nitride layer is gone, so now we nitride any that have been ground to add insurance against the common issue of crankwalk in these engines with extreme clutches and extreme use.

 

[4g63freek]

Thank you for your replys looks like I will be OK.