long time no update, so here i am with current news. well, i ended up touring with storm most of summer and fall, and the engine just sat at the place where i dynoe'd it, they said they would get to it, never did, so i ended up taking it back FOUR MONTHS LATER.(didn't get charged for any dyno or teardown time, after i went in there and explained the obvious....) brought the motor
back to the original builder, and we found some interesting stuff on top of what we had already discovered. it just never gets dull around here does it?
first off, not only did i have a smeared to hell thrust bearing, another oil leak at the rear main, but i also wiped a lobe on the solid stick, a cam i bought from supergas dil. (bummer, i was liking it!!) made great power, but it didn't like something, and i lost one lobe.(had break in/zinc additive, and a proper cam break in.....) so, new cam dead, old eagle crank holding the door open,
time to get down to details: why was the rear main leaking, and why did i have such a weird thrust surface wear pattern.
rear main:
it seems that the crank itself was the leading cause for most of my problems on this round. oh, first off, i'm pretty confident the billet aluminum cnc'd caps i was using prior to this last build were responsible for some earlier leaking. a mishap at the machinists with a too long of a bolt going through the crank hitting the cap/seal groove was the first one, when a employee hooked the motor up to his machine to run/check operation/oil pressure. and i believe heat expansion was another issue for the seal area as well. they work great on his race motors, but mine was running for hours on end, making alot more heat transfer to them, being aluminum, i think they just expanded enough to cause problems. i also had some erratic oil pressure on the last build too. with the 80lb pump, i wouldn't see more than 45psi at upper rpm's when fully hot. just an idea, but nothing else seemed to check out bad, and i don't want to blame the bop seal, although that would be the easy target. ...
the rear main seal journal had been cut and re-welded back up to spec on my first eagle, and polished smooth. well, after the last take down of the engine, (with the old caps, steel ones on this last one...)that area didn't get a real good looking at, and upon close inspection on this teardown, there are many hairline cracks and crazes, easily supplying a path for some leakage. i don't recall seeing those when it first came back from welding and polishing, so maybe after many heat cycles this developed? don;t know, not a metallurgist. it wasn't pouring out of there this time, (best seal yet, but still....) but definitely would have made a mess over time. i am pretty confident this is my problem back there, as the block seal groove checks out, the cap seal groove checks out, so all should be good with life back there. the builder has great luck with the bop seal, and despite my concerns, he/we went with it again, believing that we have solved that problem. oh, i have a new ohio crank in there now, looked great, just a little balancing, and she checked out great in the thrust area, and all other areas. so, that WILL be that, end of this story.....
thrust bearing:
it became very obvious that to us both that the thrust surface was in sad shape, and he did not check it very well. he admits to it, and has made good on it. that was part of it. after checking it out some more, i noticed that the block half of the number 4 shell moved for and aft a few thousandths, while the cap half did not. i had excessive wear on the cap half only, with the block portion of the bearing barely even kissed on the front side. they were clevite bearings, there were no extra oil provisions. i believe that when assembled, there was a mismatch between the two halves. this, and the combination of the thrust surface being less than par, could have caused the damage that resulted. the main saddle and cap checked out true when dial indicated, so this lends me even more belief in this theory. he was 50/50 on that being a problem, but there weren't many other possibilities, so, i am sticking to this theory for now.
the motor now has federal mogul bearings, with provisions for extra oiling to the thrust surface. he felt good about the setup this time, with the surfaces being true to each other, so that's where that is at. my clearances checked in a little looser than last time, (i don;t have the numbers in front of me, but i seem to recall about .003 on the mains, and .0028 on the rods...) so we shimmed the 60 pound pump a little more. i had shimmed it prior, and had about 60 psi tops, so this should bring us up to or above where we were before.......
cam:
no real clue to why i lost a lobe, just going to chock this one as a sacrifice to the 'lost a lobe' god, and call it a day. we did the break in like any other time, with no issues resulting. so, after talking to ken (p-dude) i went with a comp hydraulic roller setup this time. he spec'd out a decent thumper for my application, i am confident of hitting the 650 hp mark no problem, as i did with the solid flat tappet. damn, the expense of that switch over adds up fast! i had no idea how much lifters were for rollers, i have always been a flat tappet guy. well, i have now joined the roller club, hopefully no more sacrifices to the 'lost a lobe' god this time......(crosses fingers so i don't lose a lifter bar....
)
the cam went in fine, degree'd in great, and new pushrods were ordered after install. oh, it took awhile to get the cam, it seems that they messed up the grind, and ken had to send it back and have them grind another one for him.(thanks ken!!) i also needed to upgrade to better springs to match my pressure needs, so those were ordered from comp as well. it seems that my installed height was already at 1.800", which i had no idea, i thought i was closer to stock, at 1.65 or so. no biggie, my guy spec'd out some new springs, with just a small shimming required to get them where we wanted. he went through the heads as well, lapped the valves, everything checked out ok, so the top end looks good now too. oh, i have searched on here for distributor gear options, being my complete blower has to be removed to deal with the dizzy, i think i am leaning towards the polymer gear for potential maintenance issues, but man, big bucks! i know bop has one, and i think maybe crane? anyway, the idea of not worrying about it, and not having to tear down half of my engine to get to it is becoming appetizing i must say.....
so, the engine is done, i went and saw it today, dropped off my intake and valve covers, and he is delivering it to my house on wednesday. i am not going to dyno it this time, can't really afford it, and i am confident everything will work fine this time(i know i know, famous last words, just go along with me will ya? i am very tired after all of these problems......
i won't have solid power numbers in my hand, but i have a pretty good idea, maybe i will try to duplicate my results on a dyno program, adjust parameters to match my power results, and then just change cam specs and see what it says. i don't have one of these programs, (i'm also a mac guy, do they make dyno programs for macs?) but i will try to find someone to do it for fun if i can't.......
that's that folks, i will update when i can, after it's in the car and running AWESOME,
and let you know how things are going. hope to actually get to the track this year, so i'll keep ya up on that too.
i know there are probably mixed opinions on all these issues, maybe i few "i told ya so's", or "what were you thinking?" and some things that are/were obvious in hind sight and not wanting to admit, but really, i am just sharing
all of my info, smart decision or not, my fault or not, machinists fault or not, vendors fault or not, to enlighten the pontiac community. i am doing something a little off to the side of the ordinary engine build, and there were some unproven grounds covered in this project to say the least. but, i think all of this information may be helpful to someone else, and maybe help them prevent some of what i have encountered.
once again, thanks to all on here who have helped me though this.
i love my pontiacs, and i always hope to, difficult or not, as i am a die hard who does not want to give up. just figure it out, learn, and go beat the hell out of 'em.........
davey