My Mamo NA 434 build finally on the road!
#43
Teching In
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Well after some miles I have come across a "minor setback"
I noticed metal particles in the oil,(bronze colored stripper glitter) when I changed the oil. This prompted me to tear it down as I did not want to grenade the motor due to an apperant bearing failure.
Cam bearings looked good, rod bearings good. Got to the crank bearing and all rotating surfaces looked good. Found the thrust bearing surface wearing heavily leading me to believe that the end play was not properly set or checked when the engine was assembled. I do not want to say the guy that did the short block assembly screwed up....and start that war, I am just going to reassemble it and be on my way. The builder bored the cylinders 30 over, line-honed the mains, and blueprinted all clearances which all looked good. Obviously they missed end play.
Sent the crank to Callies to be checked and it is ok. Had the block cooked clean to get all of the bearing material cleaned out. Took the oil pump apart and it looks good.... Block is cooked clean. Waiting on a new set of bearings and the crank to come back.
For the record Tony did not do the shortblock assembly, a local shop did.
I noticed metal particles in the oil,(bronze colored stripper glitter) when I changed the oil. This prompted me to tear it down as I did not want to grenade the motor due to an apperant bearing failure.
Cam bearings looked good, rod bearings good. Got to the crank bearing and all rotating surfaces looked good. Found the thrust bearing surface wearing heavily leading me to believe that the end play was not properly set or checked when the engine was assembled. I do not want to say the guy that did the short block assembly screwed up....and start that war, I am just going to reassemble it and be on my way. The builder bored the cylinders 30 over, line-honed the mains, and blueprinted all clearances which all looked good. Obviously they missed end play.
Sent the crank to Callies to be checked and it is ok. Had the block cooked clean to get all of the bearing material cleaned out. Took the oil pump apart and it looks good.... Block is cooked clean. Waiting on a new set of bearings and the crank to come back.
For the record Tony did not do the shortblock assembly, a local shop did.
#49
Kudos to Zach for diving in and embracing the fact he might of had a problem....IMO it wasn't very cut and dry
I actually suspected he might of had center main thrust issues or should I say warned him I have seen alot of builds (even "professional" builds) go south due to builders overlooking that particular situation for whatever reason but it was difficult to diagnose from 3000 miles away in the sense that Zach was sharing pictures of his oil etc and it was hard to tell whether he had a situation or whether it might have been just normal break in. Hard to tell in a pic about the "glitter" in the oil and just how bad it was.
He certainly didn't waste any time deciding to take the engine apart again and due to that fact didn't need to repair/weld his crankshaft which is bonus. The better safe than sorry motto certainly applies here and in Zach's case his pro active stance on the situation definitely saved him money and possibly more messed up parts had he ignored it.
Zach...if your reading this the new bearings are shipping tomorrow as planned
Looking forward to the dyno figures after you get her back together
Cheers,
Tony
PS....Regarding the RPS stuff I was very much involved in the design of their carbon line of clutches and in fact used my personal C5 as the main R&D vehicle for most of the testing. The new BC2 with the flywheel perimeter lightening I offer is a pricey clutch but its not that much more than any decent dual disc and offers a wealth of upsides/benefits to the purchase. If you guys are in the market for a clutch hit me up and we can discuss some options. There are lesser priced models that offer close to the same performance for less but if you want the "holy grail" of street/strip clutches, IMO its pictured above (the same unit going behind my personal 454 in my Vette btw).
I actually suspected he might of had center main thrust issues or should I say warned him I have seen alot of builds (even "professional" builds) go south due to builders overlooking that particular situation for whatever reason but it was difficult to diagnose from 3000 miles away in the sense that Zach was sharing pictures of his oil etc and it was hard to tell whether he had a situation or whether it might have been just normal break in. Hard to tell in a pic about the "glitter" in the oil and just how bad it was.
He certainly didn't waste any time deciding to take the engine apart again and due to that fact didn't need to repair/weld his crankshaft which is bonus. The better safe than sorry motto certainly applies here and in Zach's case his pro active stance on the situation definitely saved him money and possibly more messed up parts had he ignored it.
Zach...if your reading this the new bearings are shipping tomorrow as planned
Looking forward to the dyno figures after you get her back together
Cheers,
Tony
PS....Regarding the RPS stuff I was very much involved in the design of their carbon line of clutches and in fact used my personal C5 as the main R&D vehicle for most of the testing. The new BC2 with the flywheel perimeter lightening I offer is a pricey clutch but its not that much more than any decent dual disc and offers a wealth of upsides/benefits to the purchase. If you guys are in the market for a clutch hit me up and we can discuss some options. There are lesser priced models that offer close to the same performance for less but if you want the "holy grail" of street/strip clutches, IMO its pictured above (the same unit going behind my personal 454 in my Vette btw).
#51
I don't know why its overlooked but IMO its taken down more engines than most realize when shortly after installing their shortblock oil pressure gremlins start to creep into the picture (if Zach would have let his go more he would have started losing oil pressure as well as the bearing(s) started going away).
I told Zach early on that if he had a problem it was possibly related to his thrust bearing....I was hoping he didn't have a problem of course and ultimately we know how everything worked out (good actually in light if what could have went down if it was ignored).
Perhaps some builders feel sanding the bearing is wrong and opt to leave it tight...perhaps this kind of thing doesn't even get checked in budget mail order shortblocks.....truthfully I have no idea why it happens.....I just know it does and have witnessed it personally on more than one occasion and spoken to a few other builders I trust who have seen the same.
-Tony
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Well I am back on the road, and hopefully for a while! Should be good on the end play. Sitting at .0035 exactly. Checked with dial indicator and feeler gauges prior to oiling. Did the assembly myself, checked, double, triple checked every clearance.
Been fighting idle and stalling issues which seamed to have gotten worse with the lightweight clutch/flywheel combo, but that will be taken care of with tuning. that clutch is amazing! Stocklike pedal effort and smooth as butter shifting. Absolutlely worth the money and probably the best reason for having to take the engine apart! Glad Tony suggested,(talked me into it).
Been fighting idle and stalling issues which seamed to have gotten worse with the lightweight clutch/flywheel combo, but that will be taken care of with tuning. that clutch is amazing! Stocklike pedal effort and smooth as butter shifting. Absolutlely worth the money and probably the best reason for having to take the engine apart! Glad Tony suggested,(talked me into it).
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Finally got to the dyno at Steve William's (Tuned by Frost) in Richmond VA.
I have attached a copy of the dyno sheet. The early torque numbers are very impressive.
I am happy with the results and the car is more than a handful especially after being tuned. 536RWHP and 487ftlbs of torque.
Some may have expected higher peak HP numbers but you need to keep in mind that this is an FD RX7 with a 15% driveline loss due to the IRS, and the fact that I am not able to run true dual exhaust. There is not enough room in the back so we are stuck taking the two 3" collectors to a max 3.5 single out the back fart can style. I am also running a small bullet cat in each of the collector outputs before heading to the y-pipe.
Just wanted to get that out of the way to keep any magazine racers at bay.
I have attached a copy of the dyno sheet. The early torque numbers are very impressive.
I am happy with the results and the car is more than a handful especially after being tuned. 536RWHP and 487ftlbs of torque.
Some may have expected higher peak HP numbers but you need to keep in mind that this is an FD RX7 with a 15% driveline loss due to the IRS, and the fact that I am not able to run true dual exhaust. There is not enough room in the back so we are stuck taking the two 3" collectors to a max 3.5 single out the back fart can style. I am also running a small bullet cat in each of the collector outputs before heading to the y-pipe.
Just wanted to get that out of the way to keep any magazine racers at bay.