Another motor gonna blow soon?

JDMpo0kie

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The homie George at Juju Built called me and said one of his friends has the same sputters and misfires at high boost like I had before I blew my engine.. oh boy.. we need to figure out why those sputters at high boost are happening. I couldn’t give him any valuable information other than to go to a tuner and make sure his AF ratios and fuel trims were on point. Anyone have advice o can give him? We’re gonna meet over at Driver B’s dyno someday.
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amirza786

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It's probably his rods starting to give. From what I have seen from the blown engines I have seen, if running boost above 25 to 27 psi, the engines internals should be built with stronger components
 

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The homie George at Juju Built called me and said one of his friends has the same sputters and misfires at high boost like I had before I blew my engine.. oh boy.. we need to figure out why those sputters at high boost are happening. I couldn’t give him any valuable information other than to go to a tuner and make sure his AF ratios and fuel trims were on point. Anyone have advice o can give him? We’re gonna meet over at Driver B’s dyno someday.
Check and change all Coil packs / plugs.
 
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JDMpo0kie

JDMpo0kie

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maybe keep the car stock, and you wouldn't be having these issues? :doh:
Well my car is stock but his is tuned and has e85 and all. But he called to ask me
What I found out from my blown engine but really there’s nothing to tell
 

ParkwayDrive13

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Sputters at high RPM/Boost during pulls doesn't mean his engine is going to blow.

It is more likely that he has a Fuel or Ignition problem, of which, if left unresolved, can cause engine failure.

1. Pull Spark plugs, check condition.
2. Check coolant level
3. Hows his idle? Does it stutter on start up, or sound like a Subaru?
4. Does he live in a colder climate?
5. Hows his duty cycle, fuel trims?
6. Mileage on vehicle?

I had a similar issue that just cropped up on me. Bolt on, E37 tune. After the above checked out, I reduced the gap on the plug (NGK Iridium - OEM plugs - Come pregapped at .30)

Due to my set up, and colder Midwest climate, I reduced my plug gap to .25, and problem went away. I still ended up replacing the plugs, since they ran at the OEM gap level for some time. And had some build up on the plugs.

(Shout out to D-Rob for the help)
 
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xcivicx

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I hazzard to say, that , that was a rod bending. Feel free to name it now.......
Maybe back to factory, lay off the gas for as long as possible, then see if she blows under stock conditions.
 

ParkwayDrive13

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Here are some pics of my plugs at 28k. E37 with bolt ons.

Honda Civic 10th gen Another motor gonna blow soon? 20191027_150440


Honda Civic 10th gen Another motor gonna blow soon? 20191027_150431


Honda Civic 10th gen Another motor gonna blow soon? 20191027_150419


Honda Civic 10th gen Another motor gonna blow soon? 20191027_150408
 

Design

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One thing I've noticed the community doesn't actively talk about is fueling. In the Mazda community, the HPFP was a limiting factor and replaced very early in the mod path. My understanding with the Si's fueling is that there's quite a bit of overhead. But something worth monitoring if not already.

Also, as I mentioned in the other thread, we've seen a few failing injectors on our modded 10th Gens. Not sure if there's a correlation here either. :dunno:
 

ParkwayDrive13

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One thing I've noticed the community doesn't actively talk about is fueling. In the Mazda community, the HPFP was a limiting factor and replaced very early in the mod path. My understanding with the Si's fueling is that there's quite a bit of overhead. But something worth monitoring if not already.

Also, as I mentioned in the other thread, we've seen a few failing injectors on our modded 10th Gens. Not sure if there's a correlation here either. :dunno:
Absolutely could be a correlation. Im sure this guys knock count (misfire count) is through the roof. Id say a more likely cause is plugs, or injectors.

Worst case, head gasket leaking coolant from the increased torque down low
 


amirza786

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People dont realize with a tune the car requires more care. Checking spark plugs every other month or so. Doing oil changes periodically. You gotta pay to play.
Or build the engine with better internals like @kshawn is doing
 

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kshawn

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Sputters at high RPM/Boost during pulls doesn't mean his engine is going to blow.

It is more likely that he has a Fuel or Ignition problem, of which, if left unresolved, can cause engine failure.

1. Pull Spark plugs, check condition.
2. Check coolant level
3. Hows his idle? Does it stutter on start up, or sound like a Subaru?
4. Does he live in a colder climate?
5. Hows his duty cycle, fuel trims?
6. Mileage on vehicle?

I had a similar issue that just cropped up on me. Bolt on, E37 tune. After the above checked out, I reduced the gap on the plug (NGK Iridium - OEM plugs - Come pregapped at .30)

Due to my set up, and colder Midwest climate, I reduced my plug gap to .25, and problem went away. I still ended up replacing the plugs, since they ran at the OEM gap level for some time. And had some build up on the plugs.

(Shout out to D-Rob for the help)
He 100% most likely needs to close the gap. Some see misfires pretty soon on the stock gap. PRL has a nice thread up about gapping the plugs.
 

Jes_si562

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The homie George at Juju Built called me and said one of his friends has the same sputters and misfires at high boost like I had before I blew my engine.. oh boy.. we need to figure out why those sputters at high boost are happening. I couldn’t give him any valuable information other than to go to a tuner and make sure his AF ratios and fuel trims were on point. Anyone have advice o can give him? We’re gonna meet over at Driver B’s dyno someday.
Best advice you could of gave him tb
 

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