x2 and yes, thats what was posted by the OP's dad... also that there was rod to piston contact on the inside of the piston to the small end of the rod, i wonder if it wore out the small end bushing from the "problem"
Im back w/ more bad news, broken MMR Motor
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x2 and yes, thats what was posted by the OP's dad... also that there was rod to piston contact on the inside of the piston to the small end of the rod, i wonder if it wore out the small end bushing from the "problem"
Wow, if I had to describe this thread with a single word it would be EPIC.
I ordered basically the same long block from MMR a few days ago for Winker2112's sonic blue cobra (just bought it). Interested to know how this turns out.
I also have the same shortblock/cam combo in my 98 Cobra. I had it tuned for break in by Murillo Motorsports, put 1500 break in miles on it, then had it tuned by them again and I haven't had a problem, although it's not boosted yet.
OP, hang in there buddy.
I ordered basically the same long block from MMR a few days ago for Winker2112's sonic blue cobra (just bought it). Interested to know how this turns out.
I also have the same shortblock/cam combo in my 98 Cobra. I had it tuned for break in by Murillo Motorsports, put 1500 break in miles on it, then had it tuned by them again and I haven't had a problem, although it's not boosted yet.
OP, hang in there buddy.
WOW....just stumbled accross this thread. Interested to hear the outcome to say the least. I do not deal with MMR for personal reasons, I do however have a customer's MMR 5.0L shortblock apart right now. A few questions (and observations). What is the crown height of those pistons at the valve reliefs? Second, were the egdes of the valve reliefs prepped properly (ie: no razor sharp edges or lips)? My guess is the crown height is well under 0.200". If so, that, combined with an improperly prepped piston, will create a massive hotspot extending all the way down the piston. Even if the tune is dead nuts(and PTW clearances were in spec), the extra heat can/will cause serious issues. IMO, an engine build like this should have at least a 0.225 crown, ideally closer to 0.300".
The engine I have apart here is, well, brutal to say the least. Roughly 300-400 miles on a break in tune and the car started consuming oil/smoking blue, and a few other issues. If the engine had been run harder/longer I suspect I would have found much of the same damage as the OP. Measured all clearances on this engine, and it was a jigsaw puzzle of numbers.
Here you can see the heat patterns (and this is one of the better ones)
Flycut for 0.540" cams NO PREP
Cylinder wall after 300 miles
PTW varied on this engine from 0.0035" to 0.0055", every ring gap was different and most were not square, not to mention several other things that one would not expect from a "reputable" engine building company.
Again, I have no dog in this fight, but I hate seeing people get taken for a ride. Unfortunately for the OP, this could just turn into one of those he said she said battles where in the end he will be left holding the bag.
I will give some props to MMR for what they have done with the OP, and I'll even go as far as agreeing that it was ultimately heat that cause the failure, but to just write it off as "it's not our problem" isn't the answer. Due diligence on everyone's part, and the OP/Tuner seem to be holding their end.
The engine I have apart here is, well, brutal to say the least. Roughly 300-400 miles on a break in tune and the car started consuming oil/smoking blue, and a few other issues. If the engine had been run harder/longer I suspect I would have found much of the same damage as the OP. Measured all clearances on this engine, and it was a jigsaw puzzle of numbers.
Here you can see the heat patterns (and this is one of the better ones)
Flycut for 0.540" cams NO PREP
Cylinder wall after 300 miles
PTW varied on this engine from 0.0035" to 0.0055", every ring gap was different and most were not square, not to mention several other things that one would not expect from a "reputable" engine building company.
Again, I have no dog in this fight, but I hate seeing people get taken for a ride. Unfortunately for the OP, this could just turn into one of those he said she said battles where in the end he will be left holding the bag.
I will give some props to MMR for what they have done with the OP, and I'll even go as far as agreeing that it was ultimately heat that cause the failure, but to just write it off as "it's not our problem" isn't the answer. Due diligence on everyone's part, and the OP/Tuner seem to be holding their end.
WOW....just stumbled accross this thread. Interested to hear the outcome to say the least. I do not deal with MMR for personal reasons, I do however have a customer's MMR 5.0L shortblock apart right now. A few questions (and observations). What is the crown height of those pistons at the valve reliefs? Second, were the egdes of the valve reliefs prepped properly (ie: no razor sharp edges or lips)? My guess is the crown height is well under 0.200". If so, that, combined with an improperly prepped piston, will create a massive hotspot extending all the way down the piston. Even if the tune is dead nuts(and PTW clearances were in spec), the extra heat can/will cause serious issues. IMO, an engine build like this should have at least a 0.225 crown, ideally closer to 0.300".
The engine I have apart here is, well, brutal to say the least. Roughly 300-400 miles on a break in tune and the car started consuming oil/smoking blue, and a few other issues. If the engine had been run harder/longer I suspect I would have found much of the same damage as the OP. Measured all clearances on this engine, and it was a jigsaw puzzle of numbers.
Here you can see the heat patterns (and this is one of the better ones)
Flycut for 0.540" cams NO PREP
Cylinder wall after 300 miles
PTW varied on this engine from 0.0035" to 0.0055", every ring gap was different and most were not square, not to mention several other things that one would not expect from a "reputable" engine building company.
Again, I have no dog in this fight, but I hate seeing people get taken for a ride. Unfortunately for the OP, this could just turn into one of those he said she said battles where in the end he will be left holding the bag.
I will give some props to MMR for what they have done with the OP, and I'll even go as far as agreeing that it was ultimately heat that cause the failure, but to just write it off as "it's not our problem" isn't the answer. Due diligence on everyone's part, and the OP/Tuner seem to be holding their end.
Thanks for the input.
goodluck man, i wouldn't be a happy camper either...tough break
I had MMR build my short block this summer since my original engine spun a rod bearing. I decided to go with the street mod 500. I sent them my block and crankshaft. Got the short block back and everything looked good. When I initially fired it up it had a knocking noise. This noise was very similar to the rod knock it had before being rebuilt.
I called MMR almost immediately since I was afraid to drive it making this horrible sound. I described the noise as a lower end knock and told them it sounded like a bearing or piston slap. He told me there is no way that the short block was the problem. Said his builders are the best of the best with these engines and they check everything before it leaves the shop. He went on to say that it sounded like something in the heads. I ended up driving the car about 100 miles before I decided to pull the engine.
I took the cylinder heads to the local machine shop and had them inspected. Found nothing which was no surprise. Then I took my short block to the same shop. What they found was one of the piston was .010" smaller than the rest. This was causing the piston to wall clearance on that cylinder be .012". The noise therefore was piston slap. They also found that the rod journals were tapered from one end to the other. When the crankshaft was ground it was not done properly. Also the cylinder walls all have scratches in them as can been seen below. Keep in mind this engine has 100 miles on it...
I will never use them again. I wish I would have done more research before I sent them my engine. I refuse to send it back to them because because I simply do not have any trust. I do not want to be like the OP and have them screw up 2 more times. I am cutting my losses with MMR now and will never recommend or use them again!
I called MMR almost immediately since I was afraid to drive it making this horrible sound. I described the noise as a lower end knock and told them it sounded like a bearing or piston slap. He told me there is no way that the short block was the problem. Said his builders are the best of the best with these engines and they check everything before it leaves the shop. He went on to say that it sounded like something in the heads. I ended up driving the car about 100 miles before I decided to pull the engine.
I took the cylinder heads to the local machine shop and had them inspected. Found nothing which was no surprise. Then I took my short block to the same shop. What they found was one of the piston was .010" smaller than the rest. This was causing the piston to wall clearance on that cylinder be .012". The noise therefore was piston slap. They also found that the rod journals were tapered from one end to the other. When the crankshaft was ground it was not done properly. Also the cylinder walls all have scratches in them as can been seen below. Keep in mind this engine has 100 miles on it...
I will never use them again. I wish I would have done more research before I sent them my engine. I refuse to send it back to them because because I simply do not have any trust. I do not want to be like the OP and have them screw up 2 more times. I am cutting my losses with MMR now and will never recommend or use them again!
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There's something to be said for quality local machine shops and a builder you can see in person to discuss goals... This is just getting sad!!
I feel your pain. This is why I went to Livernois for my needs, years ago. I couldn't handle customers complaining about their smoky MMR engines, and crappy power.
Install Livernois engine, blip the throttle a few times, smoke is gone, throw it on the dyno.
What determines when a supporting vendor is a predator, and what is done at that point? One concerned citizen here wants to know!
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I have used Livernois extensively with no issues. But for all my "baller" builds, L&M gets the call.
Think of it this way....
Company A advertises their 1000hp capable stroker shortblock for $3500
Company B,C,D & E all advertise the same thing for $4500-6000
Are companies B, C, D & E all crooks, or is something missing from company A's program..............
I'm kind of disturbed that I have one sitting in my car right now. I seen their posts all over SVTP when I first got into Mustangs, and figured if SVTP has them as a vendor, they cant be that bad, right?
I've got just over 1k on mine and no issues yet, hope it stays that way.
I think if people are really getting screwed like this, I say the site should drop them as a vendor. I mean, would SVTP hold On3 Performance as a vendor? No way! At least I would hope not.
I've got just over 1k on mine and no issues yet, hope it stays that way.
I think if people are really getting screwed like this, I say the site should drop them as a vendor. I mean, would SVTP hold On3 Performance as a vendor? No way! At least I would hope not.
Cylinder wall after 300 miles
What causes those vertical lines in a brand new engine? I'm just asking in general and not specifically at any engine etc. Completely un-related to this thread I have a new engine I put in a car (not my cobra) that has the same light vertical lines after only 500 miles. No issues yet, I just pulled the oil pan to take a peek and see them. Is it from the machine shop screwing something up?
I learned the hard way several years ago, that using a vendors paid status on a forum is a bad idea.
Not saying anything about MMR or this thread specifically; just in general, most forums will accept any vendor willing to pay the dues with very little oversight into their actual business practices.
Not saying anything about MMR or this thread specifically; just in general, most forums will accept any vendor willing to pay the dues with very little oversight into their actual business practices.
Here's a different question: how many 5.3's are there running with boost and no problems? I'm not trying to manipulatively change the tone of the thread; I really am curious how many MMR motors there are out there running great, especially the 5.3s, given that I've got one being built right now.
Anyone?
Also, do you guys that don't trust MMR feel there has always been a quality issue with them or that there has been a change?
I am relatively new to the car world.
Anyone?
Also, do you guys that don't trust MMR feel there has always been a quality issue with them or that there has been a change?
I am relatively new to the car world.
I have a 5.3 MMR shortblock in my car and it runs strong
I love comments look this! Then come to find out the best of the best had their heads in their asses.
And he wondered why I disassembled MY short block. Hello, you told me there was nothing wrong with it! It's redicious. Guys, I learned the hard way. Hopefully after reading through this thread you can see their quality of work.
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