Coyote #8 Question

[blackbolt22]

I remember when the 11-14 Coyotes came out, tunes were causing #8 piston damage.

Can anyone shed more light on this. Do I have to be concerned N/A if I start tweaking timing?

Does anyone have any recommendations on what I could do to protect #8 (or any other prone cyl.) as a baseline in the tune? Thanks in advance!

My thinking is that since we only have 2 knock sensors, if #8 were to start detonating first, it would limit the other cylinders potential so if #8 were to be tuned more rich (Fuel Mass Multiplier?) then timing could be advanced more safely per bank?

[Thatwhite5.0]

I believe it was a combination of a AFR that was too lean and fuel torque reduction played a role. They were heating up cylinder 8 with a lean mixture and then when they had torque reduction due to rev limiter or a parameter set incorrect, their top end completely cut fuel.
There was a flaw in the build of the 5.0 block. Cylinder 8 ran hot due to lack of channels for coolant to flow. MMR has a "head cooling mod," I believe that's what it's called. I haven't heard of cyilinder 8 failures of that type in any other year than 2011. True stock 2011 were having this failure. Stock.

I've ran 32 degrees and even tested 35 degrees on 95 octane fuel. On 91 octane, I've ran a good 27 - 29 degrees with no knock. 85k on this motor with countless 8000 RPM shifts.

I have my fuel torque ratio zeroed out. [ECM] 44775 to disabled torque reduction via fuel cut.

[bbrooks98]

I believe it was a combination of a AFR that was too lean and fuel torque reduction played a role. They were heating up cylinder 8 with a lean mixture and then when they had torque reduction due to rev limiter or a parameter set incorrect, their top end completely cut fuel.
There was a flaw in the build of the 5.0 block. Cylinder 8 ran hot due to lack of channels for coolant to flow. MMR has a "head cooling mod," I believe that's what it's called. I haven't heard of cyilinder 8 failures of that type in any other year than 2011. True stock 2011 were having this failure. Stock.

I've ran 32 degrees and even tested 35 degrees on 95 octane fuel. On 91 octane, I've ran a good 27 - 29 degrees with no knock. 85k on this motor with countless 8000 RPM shifts.

I have my fuel torque ratio zeroed out. [ECM] 44775 to disabled torque reduction via fuel cut.

I've been beating on my 2011 stock block car with twins for a couple years now. I've zeroed the fuel multipliers with the IDs, ran good fuel (e85) on the rich side .78 and somewhat conservative timing etc and it's held up, knock on wood. There may be something to the cooling mod etc, but i'm betting it was more a combination of fuel multipliers being off, Lean mixtures, fuel torque reduction leanouts and overly aggressive knock advance tables on an already increased timing map by limited knowledge early tuners.

[blackbolt22]

I believe it was a combination of a AFR that was too lean and fuel torque reduction played a role. They were heating up cylinder 8 with a lean mixture and then when they had torque reduction due to rev limiter or a parameter set incorrect, their top end completely cut fuel.
There was a flaw in the build of the 5.0 block. Cylinder 8 ran hot due to lack of channels for coolant to flow. MMR has a "head cooling mod," I believe that's what it's called. I haven't heard of cyilinder 8 failures of that type in any other year than 2011. True stock 2011 were having this failure. Stock.

I've ran 32 degrees and even tested 35 degrees on 95 octane fuel. On 91 octane, I've ran a good 27 - 29 degrees with no knock. 85k on this motor with countless 8000 RPM shifts.

I have my fuel torque ratio zeroed out. [ECM] 44775 to disabled torque reduction via fuel cut.

As god as my witness I was going to reply saying that I already have the entire fuel cut table zero'd out thanks to a really cool guy who helped me once.. and then I saw it was YOU!!!! lol

Thanks for the reply.

[blackbolt22]

I've zeroed the fuel multipliers with the IDs, ran good fuel (e85) on the rich side .78 and somewhat conservative timing etc and it's held up, knock on wood. There may be something to the cooling mod etc, but i'm betting it was more a combination of fuel multipliers being off.

With a stock car, do I need to worry about changing the fuel mass multipliers? This table only goes to 4100rpm.... so 4100+ uses the same multiplier? If I wanted to richen #8 a little just increase, right?
For instance 4100 @ .90 load is 1.00 for #8. if I went to 1.01 it would be a 1% increase in fuel?

I thought I read somewhere to increase all values under 1.00 to 1.00....

[bbrooks98]

With a stock car, do I need to worry about changing the fuel mass multipliers? This table only goes to 4100rpm.... so 4100+ uses the same multiplier? If I wanted to richen #8 a little just increase, right?
For instance 4100 @ .90 load is 1.00 for #8. if I went to 1.01 it would be a 1% increase in fuel?

I thought I read somewhere to increase all values under 1.00 to 1.00....

It's up to you. My theory was the stock values are probably off more once the injector or manifold is changed vs zero since they have been flow matched dynamically.
Granted there could be airflow differences cylinder to cylinder but i just felt like i'd never have the equipment to adjust it correctly once the injectors/manifold have changed.

Yeah 1.01 is 1% richer etc.

[Bill88stang]

you have the entire table zeroed out?

[bbrooks98]

you have the entire table zeroed out?

Zero was a bad term to use. Basically i have them all set to 1 similar to how the Roush files come setup.

[Bill88stang]

oh ok I was just wondering because my whole table is set to 1.0 just making sure I wasn't missing anything

[realspeeddan]

When you hit certain ones (of the many) factory torque limits, the factory strategy reduces torque by reducing fuel, overriding fuel back to stoich. The fuel reduction kicks in on a timer. Spend more than 10 seconds above the torque limit and the computer will start to pull fuel out to reduce torque. This is why most of the guys melting pistons were guys doing top speed runs, i.e. holding it at WOT for more than 10 seconds.

You can hit these limits on a STOCK car. What usually saves the car on the stock tune is that exhaust catalyst/flange /O2 sensor temperature protection limits override everything and richen the mixture back up once the calculated exhaust component temperature gets high enough, before the pistons melt.

Most of the guys who melted pistons had the cat temp protection shut off, so that never kicked in to richen the mixture back up.

The proper fix is to adjust the appropriate torque limits so it never tries to lean out to reduce torque in the first place. You can also change the "override" fuel ratio to something richer, although that sometimes cause a stumble or idle surge in certain conditions.