On my breif visit home, I managed to get the Nitrous motor apart so I could get the heads off so they can be updated and have it freshened up. After having my own opinion on how the internals look, I had my local race engine guy have a look since he will be doing all the double checks on the measurements, honing, and cam bearings.The Crank clearance need to be looser on the mains and tighter on the rods last time I checked them. For a nitrous motor and especially since its a Buick, he told me that bearing, cap surfaces, pistons, rings, and bores all looked really good! No cracks, no breaks but my lifter plates had all broke loose and one was sitting in the back of the lifter galley. I will be buying a TA bar as the fix. He did have a bad motor to show me, it was one of my buddies Ford Motorsport Winsor block that WAS a nitrous motor with a crack up the front of the block to the main bearing and really bad chattering between the main caps and block. One thing I mentioned was that I thought the rod bearings seemed to be getting hot by the smell and look on the back side of the bearing. I was told it was normal but being a nitrous motor, and with all his experience on round track motors, he told me that since I run synthetic that the synthetic doesn't absorb and take away heat like normal oil does. He explaned that was one of the reasons you don't see it burn up in the pan on the comercials you see on tv. I like synthetic and felt it kept my Buick alive with the low oil pressure(55psi hot w/8-10in vac.) problem I've always had but what have other people heard about heat transfer with synthetics. I would like to know. I did have one casualty, the cam! I had my complaint over it when I first bought it from TA over duration variance (267-270 intake/274-278 exhaust)and about it being an actual "new" cam. Well, I though it might have been tracking on the lobes the last time I took the motor apart but only on the back of the cam where the base circle was more in the core. This time it actually broke through the heat treatment on the top of the lobe on the very back lobe so in the trash it goes. I guess I'm glad it failed on me before I passed it on to someone else and they had the problem. It did run good so I can't compain on that issue but the lobe failure makes me mad. If it wasn't for TA we would have the parts we have but some of the parts I get make me want to choke somebody.
I would speculate that the heat on the rods was probably due to the low oil pressure and so-called hemmorhaging from the big mains. The synthetic is probably what kept it alive. Did you read the article Alan posted on the 0W-10 and no oil pressure?
here is a decent article that contradicts your machinist. Keep in mind that it is written by Redline, and not GM Motorsports.
thanks for the oil article. It was good info. I'll stay with my synthetics and give my motor another good beating as soon as its back together.
