We turned our 230 in excess of 5000 rpms for years with no bearing problems, so its not the crank per se - if the oiling is going well? Any pictures of your bearings? I'd sure like to see what's going on there too. I seem to recall a conversation we had about harmonic dampers and that you were running a naked crank snout. About every little mopar I've seen has a mismatch between the oil hole in the main bearings and the supply hole in the main bearing saddle. You either have to relieve the block to match the bearings or elongate the bearing oil hole to match the block - could this be the problem? Maybe numerous little sins that almost added up to a big failure - good thing you took the chance to blueprint it. Keep us posted, please. Hud
Oiling is my suspicion right now- at the top of the list is filtering- you guys will probably laugh at me for this, but, during the build I asked the machinist about leaving off the filter. The stocker is bypass, so I figured if I change the oil after every race, it's doing as much as a bypass filter. Unfortunately, 30 dyno pulls is more like a SEASON of racing, not ONE RACE, so the oil was DIRTY. I'm trying to figure out full pressure filtering right now. second is the crank- I had it cross drilled, and I want to go back and look at all the holes and remind myself what was done. If it needs further drilling, or even some plugging, now is the time. bearings- it had Clevite 77's, anybody have any input as to quality, design, or alternatives? They were installed as manufactured.
I'm thinking oiling too. The reason being this is a main bearing problem. Even rpm related failures happen at the rod journals. If things start going bad at the mains, everything else is screwed. I'm thinking by the time you get done with this project, you'll have surpassed us all in expertise. The best knowledge is born of adversity. Hud
started measuring the crank tonight, just for shits n grins, started rapping around on the weights- the front main and #1 rod don't have that nice crisp, pretty ring that the rest do. That's not exactly inspiring me with confidence at this point.
oil pan 2" deeper than stock, kicked out 1" on the right side, plus windage screen 6 quarts of Brad Penn 30wt
crank magnafluxed ok, journals mic'd ok, still have to measure rod and main housing bores, install bearings and remeasure.
I'd like to take pics of the bearings for everybody interested, but my crappy digital camera takes HORRIBLE close ups, all you'd see was blur. I asked my builder about the balancer, before understanding what its true function is. I thought since the engine was balanced, perhaps that could be eliminated. The factory unit is little more than a weight and pulley bolted to a hub. The builder told me "yes". The hub remained, while the rest was eliminated. Found out later, after the damage was already done, that I NEED that DAMPER, not for balance, but for harmonics. I intended then, to put a damper on before racing, but then the opportunity came to blueprint, so I took it. good thing I did, catastrophic failure sucks.
Its possible that the damage was from dirt/grit/shavings from your build. I've seen that kind of unexplained bearing damage before - and it was crank grinding refuse trapped in the oil passages. We always scrub the crank out with a gun cleaning tip/rod - just in case. Block oil galleys too. I still haven't found the main saddle and rod bore dimensions - I don't know where I found them before or where the heck I wrote them down. Its been too long since I did such. Hud
Mark- thanks for looking! I got those dimensions from a local machine shop that does alot of old stuff. I would have probably gotten the crank back in the block last week, except we had a couple "snow days".
a blueprinting update- the main housings (and, subsequently the main bearing oil clearances) were all over the place, align honing an absolute necessity. the rod housings were PERFECT, as were the rod bearing oil clearances. the valve guides were WAY loose. I'm going to correct the mains, the guides, and replace the rings (and the bad bearings), and get 'er back together so I can GET ON WITH IT!
The valve guide looseness may have contributed to your rpm ceiling. Mopar stock valve springs aren't going to let you go above 6000, if the valves are bouncing around trying to seat, even less. You may have found your silver bullet. Can't wait to see you put her back into action. Hud
I think at least part of my rpm issue was the carb linkage I had at the time of the dyno runs. the geometry was WAY off, but I didn't notice it until I put the modded carbs on. All that is now fixed. The valve springs in this engine are better than stock, so at some point I hope this thing is at least CAPABLE of more rpm, even if it won't make power up there.
WOW!!!! I can't believe it's been a YEAR since I posted to this thread!!!!! Not that I've had much to report... After a stint with unemployment I've been back to work since July, but I'm just now getting a few bucks ahead to get the HA/GR back on track (pun intended). I ordered ARP main studs today, as soon as they show up the block goes to the machine shop (different shop than the botch-job from before) for align honing. It'll be slow going, but I hope to have the engine back to operable condition for 2011.
Have that crank checked again, too. Anything that doesn't 'ring' the same end to end makes me nervous.... Congrats on the job and Good Luck on the motor!!!
By all means have the crank rechecked. If it doesn't ring the same from both ends, you have a problem. It might not be a surface defect (crack), but could be a subsurface defect in the material. If it was mag'ed using AC, subsurface defects could be missed.
The Jalopy Journal
