- Thread starter
- #101
Thanks, I'll look into it. What does that entail? I've never heard of this. Piston rings seem a likely culprit, but I'm told I'd need a rebuild for that...
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S197 BackInBlack Build Thread Profile - S197 Mustangs
- Thread starterBackInBlack
- Start date
Chassis Swapped Boss 302
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- Thread starter
- #102
Looked it up... I thought this might be possible but the couple guys I've talked to about it said I might as well replace the engine considering the cost. I'll ask what it'd take...
Dave_W
Cones - not just for ice cream
I'm no expert on this, but the cost kinda depends on how bad the existing engine is. The starting cost is to tear down the engine and measure everything. At that point, you'll know what parts need replacing or machining. You might get away with a light cylinder hone and new rings, plus new bearings, seals, and gaskets. Probably replace valve springs since you're in there and don't know how the engine was treated before you got it. Consider the PAC-1234x springs, but know they may not be allowed in some competition classes.
Worst case, a cylinder is scuffed or warped so badly you need to sleeve the cylinder to fix it, and that's when you consider a new block. Or a crank journal is scored and can't be fixed with machining to a standard undersize. Same thing for other parts - are they still in tolerance, or can they be brought into spec with a little work, or do they need to be replaced.
The key is having this done by someone who knows what the acceptable tolerances are for the [Coyote / Roadrunner] engine. Preferably they have an in-house machine shop or have a close long-term relationship with one.
Worst case, a cylinder is scuffed or warped so badly you need to sleeve the cylinder to fix it, and that's when you consider a new block. Or a crank journal is scored and can't be fixed with machining to a standard undersize. Same thing for other parts - are they still in tolerance, or can they be brought into spec with a little work, or do they need to be replaced.
The key is having this done by someone who knows what the acceptable tolerances are for the [Coyote / Roadrunner] engine. Preferably they have an in-house machine shop or have a close long-term relationship with one.
- Thread starter
- #104
Trims no longer improving, I'm averaging around 9%. Some days 6%. some days 11%, usually 7-8%. I do feel like I have slight improvement, but overall the car is still running about the same as it was before. So I did an oil change today. A local shop that stocks Amsoil owed me a free oil change so I did that. Glad I can drive normally again. Car is scheduled for a tune on the 14th. We'll see what the tuner says. Will definitely go in for a, "refresh" if it's a better option than a new engine. If not, I'll probably run this engine into the ground a bit, have some fun with it and plan for a new one sometime next year or something. Will continue working on restoration bits. I think the I need to get the trunk painted, it's starting to crack a bit. Do a couple more weatherstrips, etc. while I wait.
302BOB
Epic Contributor
BnB., Reading your posts makes me SO glad my Boss is where I like/ need it to be............AMEN!!!!!!!!!.......... Some day you may finally enjoy what you have....until then, you have my best wishes!!!!!!!!!!!
- Thread starter
- #106
It's alright! I gambled on a salvage build and got a less than perfect outcome
It happens! I'll just have to enjoy the build as a part of the journey I'm still proud of the work I've put in and it's been a huge learning experience. Glad you can enjoy your Boss!How's Peanut?
302BOB
Epic Contributor
BnB, When you finally get to enjoy the result of all that you went thru..............you will enjoy it that much more!!!!!...your middle name isn't Job, by any chance, is it????
302BOB
Epic Contributor
Peanut is doing GREAT!!!!..........Hon taking Him to get His stitches out Monday.....Like I mentioned before....He IS a TROOPER!!!!!
- Thread starter
- #109
Hey guys, easy question. This will be my first ever dyno tune, and really my first tune I've ever had done to any of my cars. I know that with an e-mail tune, you get the file and then you load it and your tuning device saves a backup of the stock tune. With a dyno tune, do they modify the software in-place, on the car as-is? Meaning I would lose the stock tune if I didn't back it up first? Should I arrive at the dyno tune with a canned tune loaded so I can have my backup properly stored? Will tuners generally give you the digital file from the tune in case you need to return it to stock and then flash the tune back?
I have an SCT X4. So I think these are my 2 choices:
I have an SCT X4. So I think these are my 2 choices:
- Go in stock and get the car tuned. If the tuner doesn't give me a stock file, I could flash a canned tune to get the sw copy of the dyno tune which the tuning device would save as the stock tune. I have already backed up a copy of my stock tune so I think I'd be able to switch back and forth in this scenario.
- Go in with a canned tune. If the tuner does give me a file, my stock tune is properly saved and ready to reload when necessary.
- Thread starter
- #110
Had the free Amsoil oil change done this weekend. Glad to get the chemicals out of there so I can hit normal RPMs. 1st datalog shows 4% fuel trims. If this continues, I may have to join the cult!
steveespo
@21CarProductions @NJS58 Racing @NJS58 Eurosport
STFT above 1.5% indicate a vacuum leak, bad MAF sensor or bad primary O2 sensors. Need to look there. The ECU is adding fuel in response to unmetered air or poor sensor performance. Any MAF correlation or O2 performance should set codes. I chased a vacuum leak that turned out to be a cracked runner on a new Boss 302 intake manifold. Crack was so tiny I thought it was a cob web. Covered it with RTV and the trims went to .02%.
- Thread starter
- #112
Thankfully it's not that bad! This is LTFT of 1.04% (today, anyway). Shaun @AED wanted me below 1.05%... Today was actually the first day I've logged a number low enough. Down from highs of around 1.19% after having been through all potential vacuum leak possibilities, it seems I've got some minor piston ring problems.
I got a local tuner who is willing to tune the car, so I'm gonna try to paper it over with a tune and ask what the tuner recommends engine-wise. I wouldn't mind replacing the piston rings if the price is right, but somehow I doubt I'll find anyone who can do it for a cost that makes it worthwhile.
- Thread starter
- #113
I must say, I'm liking this Amsoil 5W-50. It does seem that it helped my engine a bit. I've still got a spare 9 qt. of Motorcraft to use in the garage, but I think I'm officially joining the Amsoil cult.
10 more days til Dyno tune! Will update when it happens. Tuner is trying to talk me in to going E-85. I'm concerned about putting too much strain on my junkyard engine... We'll see. For now my future plans are nothing more until I do the 100k mile maintenance (next year), which will include timing chains, oil pump gears and probably L&M intake cams, etc. Will probably do E-85 at that time and switch back and forth. But I think my engine will be OK. Imperfect, but OK.
10 more days til Dyno tune! Will update when it happens. Tuner is trying to talk me in to going E-85. I'm concerned about putting too much strain on my junkyard engine... We'll see. For now my future plans are nothing more until I do the 100k mile maintenance (next year), which will include timing chains, oil pump gears and probably L&M intake cams, etc. Will probably do E-85 at that time and switch back and forth. But I think my engine will be OK. Imperfect, but OK.
- Thread starter
- #114
Wellp, looks like this is the end of the road for BackInBlack for the time being. Did my best to get it running right, but the tuner says they can't tune it. I don't think they figured out what's wrong with it but whatever it is it must be the motor. They're writing up a report for me now. At least I'll have a dyno sheet to show for it.
This build will be completed hell or high water. But I can't justify replacing the motor right now. For now, I'll drive it for a while and see how it holds up. I'll make plans on a replacement some time in the not so far off future. I'm thinking an NA Aluminator, or a built gen 3 along with the boss heads if they can be saved. For now I'll just focus on making sure it rides right and maintaining it until the time is right. Will post details when I get them...
This build will be completed hell or high water. But I can't justify replacing the motor right now. For now, I'll drive it for a while and see how it holds up. I'll make plans on a replacement some time in the not so far off future. I'm thinking an NA Aluminator, or a built gen 3 along with the boss heads if they can be saved. For now I'll just focus on making sure it rides right and maintaining it until the time is right. Will post details when I get them...
- Thread starter
- #115
Here are some details from my most recent diag session with the local Mustang tuner. While my recent visit to the new mechanic was pretty thorough, I feel that this tuner really checked just about everything that could have been checked. Previously, I went to a new mechanic who has a lot of computer diagnostic equipment available to try to have them diagnose my symptoms. For the most part, they ran a whole bunch of Ford IDS tests and everything came back well within spec. That mechanic thought I may have piston ring issues. The mechanic I built the car with thinks everything is fine and I should let it be.
I went in to the tuner under the idea that I'd get a look over and then a tune just to try to get things running as well as possible. The tuner looked over the other things we've checked and verified our findings were correct, and then did a test dyno run to look for issues (unfortunately, no WOT pulls). He says my fuel trims at this point are acceptable. He logged 4% LTFT at idle while I was there and near zero under load. More interestingly, we logged a rare misfire on cyl 3. I actually knew about this already, I see in my mode 6 data that my car logs a rare occasional misfire on cyl 3. The tuner also noted that my car vibrates more than it should. He then ran something called a, "cylinder balance test", and this showed that the output of cyl 3 is slightly weaker than the rest, although still within spec and not enough to throw a code. He ran a full compression test, and these are the results: cyl 1-5: 190, cyl 6-8: 195. No problems there. Pretty good actually. He did a leakdown on cyl 3 and we got 4-5%. Well within spec. He noted that some of my spark plugs were a little brown. These are new Motorcraft double platinum's (what the manual recommended) that we installed when we built the car at the end of 2023. There is about 10k miles on them now. He scoped cylinder 3 and it was pretty clean and the valves in there were working properly but we did find scoring on the cylinder wall. He noted that he was surprised the leakdown result was so good considering the scoring. He swapped the cyl 3 spark plug/coil with a different cylinder and logged, but there was no change.
In the end he couldn't be sure as to the root cause of the symptoms. The most interesting piece of information gained here is that my engine is running well within spec aside from the fact that cyl 3 has a slight problem.
The tuner gave me possible causes as: imbalanced flywheel (it's new from my recent transmission rebuild and this issue predates the transmission rebuild -- not impossible though) or a crankshaft imbalance (he notes that it'd fit the symptoms but he'd be surprised if this was the case).
The only recommendation he had for me was that I put in some new NGK Iridium spark plugs, which are on the way now. Other than that, they said I'll have to wait until the symptoms get worse and make it easier to diagnose.
He did try to tune the car but was unable to compensate for the issues. He said it'd do more harm than good. So I'm stuck stock. I'm like a 2025 Mustang (before they cracked it). I've thought about it, and I think I will follow this advise and hope that whatever the problem is presents itself at some point.
Here's some engine porn from cyl 3:
I went in to the tuner under the idea that I'd get a look over and then a tune just to try to get things running as well as possible. The tuner looked over the other things we've checked and verified our findings were correct, and then did a test dyno run to look for issues (unfortunately, no WOT pulls). He says my fuel trims at this point are acceptable. He logged 4% LTFT at idle while I was there and near zero under load. More interestingly, we logged a rare misfire on cyl 3. I actually knew about this already, I see in my mode 6 data that my car logs a rare occasional misfire on cyl 3. The tuner also noted that my car vibrates more than it should. He then ran something called a, "cylinder balance test", and this showed that the output of cyl 3 is slightly weaker than the rest, although still within spec and not enough to throw a code. He ran a full compression test, and these are the results: cyl 1-5: 190, cyl 6-8: 195. No problems there. Pretty good actually. He did a leakdown on cyl 3 and we got 4-5%. Well within spec. He noted that some of my spark plugs were a little brown. These are new Motorcraft double platinum's (what the manual recommended) that we installed when we built the car at the end of 2023. There is about 10k miles on them now. He scoped cylinder 3 and it was pretty clean and the valves in there were working properly but we did find scoring on the cylinder wall. He noted that he was surprised the leakdown result was so good considering the scoring. He swapped the cyl 3 spark plug/coil with a different cylinder and logged, but there was no change.
In the end he couldn't be sure as to the root cause of the symptoms. The most interesting piece of information gained here is that my engine is running well within spec aside from the fact that cyl 3 has a slight problem.
The tuner gave me possible causes as: imbalanced flywheel (it's new from my recent transmission rebuild and this issue predates the transmission rebuild -- not impossible though) or a crankshaft imbalance (he notes that it'd fit the symptoms but he'd be surprised if this was the case).
The only recommendation he had for me was that I put in some new NGK Iridium spark plugs, which are on the way now. Other than that, they said I'll have to wait until the symptoms get worse and make it easier to diagnose.
He did try to tune the car but was unable to compensate for the issues. He said it'd do more harm than good. So I'm stuck stock. I'm like a 2025 Mustang (before they cracked it)
. I've thought about it, and I think I will follow this advise and hope that whatever the problem is presents itself at some point.Here's some engine porn from cyl 3:
- Thread starter
- #116
New suspect: Cylinder 3 rod bearing. From what I can tell this would account for all symptoms. If this is the case, it should become apparent before long...
I'll continue to maintain and be careful, but if this is the issue I don't think there's anything I can do except wait for the inevitable. In the meantime, I'll build a list for a small block swap. ... How's an aluminator swapped, Boss swapped V6 sound? lol
I have the feeling this engine may take a little while to give up the ghost though.
I'll continue to maintain and be careful, but if this is the issue I don't think there's anything I can do except wait for the inevitable. In the meantime, I'll build a list for a small block swap. ... How's an aluminator swapped, Boss swapped V6 sound? lol
I have the feeling this engine may take a little while to give up the ghost though.
Dave_W
Cones - not just for ice cream
If it's the bearing slowly going away, you might want to take oil samples for analysis every few thousand miles to detect the amount of metal in the oil. Don't need to do a whole oil change. You can also change filter more often without an oil change, and cut the filter open to inspect for sparkly bits.
SPEEDiagnostix Oil Sample Kit - Coyote Specific
Specializing in performance upgrades for the 2015+ S550 Ford Mustang.
www.opmustang.com
- Thread starter
- #118
I'll do it. I think this one has a pretty good chance of being the real culprit. I'd be looking for copper, right?If it's the bearing slowly going away, you might want to take oil samples for analysis every few thousand miles to detect the amount of metal in the oil. Don't need to do a whole oil change. You can also change filter more often without an oil change, and cut the filter open to inspect for sparkly bits.
SPEEDiagnostix Oil Sample Kit - Coyote Specific
Specializing in performance upgrades for the 2015+ S550 Ford Mustang.www.opmustang.com
Dave_W
Cones - not just for ice cream
I think the Coyote/Roadrunner bearings are bi-metal, so an aluminum alloy with some silicon and maybe a bit of tin for the wear layer.
- Thread starter
- #120
Hmmm. I found a post here on TMO by @TMSBOSS where he talks about replacing a rod bearing in a Mustang GT. It was only one cylinder and there was no crank damage. Could it be possible I'm in the same boat? Since these cars have forged crankshafts, could I get by replacing just the bearing? It's worth looking into. I already know what cylinder it's gonna be. And my knock, if you can call it that is very faint so it sounds like my situation is better than the car he worked on...
