Broken engine: my piston melted

[amrazM]

Originally Posted by ///M3Fresh

Stock fuel is variable no? so 3-6bar pending load... thats a peak of ~88PSI/injector. @100% duty.

If you want to make 560 (425RWHP + 10% room) Crank HP on E85(let me know if this is realistic as I dont know many S65s making this sort of power without boost/stroking. Just work the math backwards..

1/2lb of fuel is what you need per CHP per. So youll need 280lbs of fuel @ 100% duty cycle. 280/8 = 35Lbs. 3Bar ~43lbs injector.

Can do the math in stock form for you too. 414CHP = 207lbs of fuel. per injector that looks like 25-26lbs. add 30% for E85 and youre at ~34lbs.

Originally Posted by Redd

The stock injectors can run E85 no problems. My friend tried E100 for a short period. Injectors also ran that fine but he melted the fuel pump.

Ultimately it comes down to something actually really simple, considering your numbers which puts you around 71% for a perfectly running fuel system on a 10yr old car, unlikely, in the real world where your car likely isn’t perfectly running and your fuel system is like it came out of the factory 10 years ago you’ll probably be at or near 80%idc which FYI is considered “maxed” out as an industry standard. Even with that it still doesn’t really capture the point here if you’re pushing the car to do something it simply wasn’t intended to do and with that comes with inherent risk of something going wrong which in this case could have been an injector stuck open and took out the cylinder.

At the end of the day, your car your money run all the E you want on an otherwise stock car with no return.

[pbonsalb]

I agree with you about the risks of E85 without a flex fuel sensor and a tune that adjusts fuel and ignition to match, but I do not think 10 year old engines use 12.5% more fuel or that, even if they did, 80% duty cycle is anything to be concerned about. I also think the math in the earlier post calculating BFSC was conservative— I doubt the S65 actually runs at a BFSC of 0.50 lbs fuel per hp for pump gas.

[NeverL8]

Originally Posted by Longboarder

I hope you are right that it goes away. I had to get the M8 base model because the M8 competition has exhaust burbles with the valves open and i wanted to crash the car straight into a wall after 2 minutes on the test drive. Fortunately it could be turned off.

People who constantly accel and decel and subject us all to their Burbles and crackles are pure asshats.

The crazy thing is...they think it’s cool, while 99% of people think it’s retarded and sound like car is farting. I see clowns around Carlsbad driving around accelerating/decelerating and then look around to see if anyone noticed it.
I guess bad attention is better than no attention at all :

[Scharbag]

Originally Posted by TheRussski

The crazy thing is...they think it’s cool, while 99% of people think it’s retarded and sound like car is farting. I see clowns around Carlsbad driving around accelerating/decelerating and then look around to see if anyone noticed it.
I guess bad attention is better than no attention at all :

Yup - modern fuel injection should not burp and fart - leave that shite to carburetors.

My tuner accidentally sent me a burble tune once... Scared me half to death. Why would anyone want to do that to their car?

Dumping raw fuel into the engine is a recipe for cylinder wash, oil dilution, ruined cats, excess stress on exhaust valves and failed O2 sensors. Not to mention the ridiculous fake sounds...

To each their own, but Bosch, Denso, Delphi etc. spent a great deal of time and effort to ensure a clean, efficient fuel injection system on modern cars. Why would anyone or any manufacturer choose to ruin a precision engine management system by introducing fake off throttle overrun?

/end rant

[LakeSurfer]

Lol at burple tunes.

I don't know a ton of people but I do go to a ton of car shows and cars and coffee events and I have never heard a single person who wasn't the driver of the car say anything good about those tunes. Even guys with the tune hate on other guys with it.

Some Mercedes bi turbo v-8 pulled up next to me that sounded amazing and then he let off and it sounded like gun fire but even louder. No one was impressed. Might as well be a Honda actually I'd prefer the river guys over these so called "tuners".

[kyrix1st]

I don't completely blame him; there is a certain satisfaction of running the car hard and then hear the exhaust pop a few times, although working the car hard to hear it is the major part of fun. Burble tune is too excessive and inefficient.

[chocstraw]

Originally Posted by Redd

The stock injectors can run E85 no problems. My friend tried E100 for a short period. Injectors also ran that fine but he melted the fuel pump.

throwing my $.02 in, I got distracted while pumping E85 and accidentally pumped 11 gallons into the tank instead of 3-3.5. I spent a couple hours driving very conservatively to burn up the excess E85 and when I got back home, INPA had 83 "engine running too lean" codes. The oil temps were also noticeably higher. Even with a tune, the fuel pump isn't up to the job. I replaced my plugs and had my RBs done, the porcelain and cylinder walls looked fine, but I wouldn't do it again.

aside from being flat-out annoying, there are enough issues that can be attributed to burble tunes on port-injected engines like the S65: melted and clogged cats, throttle butterflies melting off, and high cylinder temps.

[mtx450]

Not to get caught up in this sweet internet battle, but a lot of you guys are missing the point of E85. Yes, it obviously requires more fuel. But just "adding" fuel doesn't do much. The whole point of E85 is to run more advanced timing without detonation, therefore creating more power. The only way to accurately do this would be to run a dedicated E85 map. Even still, I can't imagine the gains would be worth it. The huge gains on E85 are normally realized on a forced induction setup (like a turbo, etc).

[Green-Eggs]

Originally Posted by Throatpunch

An open injector can't throw enough fuel into tjecylinder fast enough within a full cycle to create by hydrolock

There have been a half dozen (or so) engines blown with a verified stuck injector, causing bent connecting rods. So yes, it can happen on S65.

[Green-Eggs]

Originally Posted by amrazM

im guessing the photo from the boriscope is from cylinder 8, the bore is destroyed from the washdown of your flame tune

My $$$ would be on #7 because it's the only cylinder in the S65 that fires sequentially after it's adjacent cyilnder (#8). When a supercharged S65 blows and melts a piston, it's almost always #7 because it can't dissipate the heat fast enough. Same thing happens on Chevy's with #2 -- which fires sequentially after #1. In fact, all cross-plane V8's have two adjacent cylinders that fire sequentially.

[M3inthecity]

Interested to see if it’s a piece of porcelain from the spark plugs that melted.

[remi34000]

Originally Posted by M3inthecity

Interested to see if it’s a piece of porcelain from the spark plugs that melted.

Toutes en bon état

[jvictormp]

Originally Posted by Throatpunch

An open injector can't throw enough fuel into tjecylinder fast enough within a full cycle to create by hydrolock

My theory is still a lean engine due to e85

U need to add 30% more fuel to make it operate in normal combustion a/f

I had a stuck open injector. Emergency mode, pulled car over and towed to the shop.

When mech pulled out the injector, the intake valves were fuel flooded. Lacked just a little time for me to blow the engine.

[yidgyi]

Can you check if all ITB's are ok? I had a similar failure point on my S65 and one of my ITB's broke and stuff fell into the piston.

I also had a gintani burble tune for over 2 years and never had issues. I suspect my failure point was a backfire into the ITB's which caused too much pressure and a ITB screw loosened over time resulting in broken pieces going through the valve into the piston. It was never confirmed by an engine specialist, just me, a DiY'er.

The hate for the burble tune is insane lol. Leave people to do what they please with their motors. I've had tunes of all types and Gintani's is by far the best.

[akkando]

Originally Posted by jvictormp

I had a stuck open injector. Emergency mode, pulled car over and towed to the shop.

When mech pulled out the injector, the intake valves were fuel flooded. Lacked just a little time for me to blow the engine.

What year was your car. Seems like my2011 has had this more than others.

[remi34000]

My car is 11/2008

[jvictormp]

Originally Posted by akkando

What year was your car. Seems like my2011 has had this more than others.

Sorry for late reply, MY 2008