Quote:
Originally Posted by Drift_FX
haas anyone mentioned these yet?
these make a huge difference for high reving motors.... the oil supply to the rod bearing is greatly increased...
(to my knowledge these are only for sr20 motors) |
Those are gtir bearings, Found stock on the gtir fwd SR. You need to machine, "Groove" your main journals to benefit from this bearing. They look to be Calico coated as well, which IMO is one of the best things you could do for a bearing. Coatings/ dry film lubricants are what sold me when I built my engine. they are highly effective in reducing friction, heat, and surface galling. Added benefits is the coatings loading/pressure limits and the ability to retain oil much better than a un-coated bearing...
As far as bearing clearance goes, it's all dependent on power goals. Hell, when I opened up my motor to build it, I was curious to what clearances were after it been beat on at 21lbs, 300hp for 3 years. The oem bearings had worn to .0016-.0020 anyway and I was still making great oil pressure( granted, the motors questionable previous life)... far from .0002-.0009 oem range...
I built my motor A tad on the loose side, .0022-.0025 mains, .0025 rods. Again, 430-450hp goals
They are loose ONLY because I intended to use a coated bearing. My tuner put together a sr a while back and wanted to experiment with "clearance vs. longevity" on a coated bearing and ran WILD loose clearance (35 rod and 30 main)That setup was still running great 4 years later, 450 rwhp... my opinion, I wouldn't go past 20 on main and 25 rod on un-coated bearings that wanted longevity
I think there is quite an advantage running the coating, not only on bearings and piston skirts,(dry film) but also thermal barrier crown coating on the piston tops.
P.S. Get yourselves some mit mic's
