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Blew up my Boss motor on a track day - Why???

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Fabman

Dances with Racecars
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Pleasanton: 1/2 way between Sonoma and Laguna Seca
That’s great intel that the Ford tunes address the throttle lag. I have an AED tune on mine and the throttle lag drives me crazy. I reached out to Shaun to see if this could be tuned out - here’s the exact response:

“Torque based system with 26 individual tables based on cam position load, and RPM. Not ‘easy’ to adjust this and therefore we do not. Far too time consuming”

Perhaps Shaun could review the tables from the TracKey tune and replicate without having to reinvent the wheel - just not sure if he would have visibility to the Ford tables.
Sounds like your looking for something like this:

I have no idea if this is worth a dang but I've seen it endorsed by people who I would think should know.
 
Octane requirements already beaten to death.

Next thing I suggest considering are piston cooling jets or ‘squirters’.

And do you still have the OEM oil to water cooler?
Yes I do still have the OEM oil to water cooler. In addition I have a 72 row Setrab oil cooler with a Moroso sandwich plate. I recall reading through many of your posts and you eliminated your OEM cooler correct? How does it work for you and your set-up? Do you recommend eliminating the stock cooler and going with or without a thermostat in the sandwich plate? At some point throughout the year in Minnesota we have some pretty cool mornings for track days in September and October.
 
Update on engine that was removed.
#8 piston was was totally destroyed and in many pieces. Part of the rod was connected to crankshaft.
#4 piston was still in the block and the rod without the cap was wedged in the valley area between the heads.
Oil pump gears were intact and looked good. Oil pump intake was full of small fragments so it must have been working during the explosion.
All valve springs and valves were fully intact.
IMG_7328.jpgIMG_7331.jpg
 
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xr7

TMO Addict?
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Minnesota
So if I like the Track Key sounds like I should not slap on a set of headers.
The throttle response is so much better with the Red key.
And the next question is can the "octane adjust" setting be checked to see what it is set to?
You will learn more here by accident than elsewhere by design.
 
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Sounds like your looking for something like this:

I have no idea if this is worth a dang but I've seen it endorsed by people who I would think should know.

I’ve seen these, but haven’t looked very closely as I already have the Xineering blip module wired on the TPS with their inline harness. Seems like trouble with 2 devices trying to manipulate signal there. The car had a BAMA tune on it when I first bought it, and throttle response on that tune was much crisper than AED’s, so I know it’s possible. I have learned one thing though - if Shaun doesn’t feel like doing it, there’s absolutely no sense asking again.
 

Grant 302

basic and well known psychic
Yes I do still have the OEM oil to water cooler. In addition I have a 72 row Setrab oil cooler with a Moroso sandwich plate. I recall reading through many of your posts and you eliminated your OEM cooler correct? How does it work for you and your set-up? Do you recommend eliminating the stock cooler and going with or without a thermostat in the sandwich plate? At some point throughout the year in Minnesota we have some pretty cool mornings for track days in September and October.
I still have the OEM cooler on both cars. I was only asking to ‘eliminate’ or avoid potential future oil cooling problems. You should be good in that regard keeping them both.

I would only recommend the delete if using in competition and/or if concerned about the coolant line failure.

Main thing I’d suggest is the possibility of adding oil squirters or starting with a short block that already has them in. I’d do it if I ever have to rebuild my Boss, and would certainly keep them in the GT. With the two coolers, you should be able to add the squirters and keep your pistons cooler.

@Mad Hatter is one who has added the squirters to his Boss for his latest engine, but hasn’t run on track yet. So looking forward to his data when it’s available.
 

Grant 302

basic and well known psychic
So if I like the Track Key sounds like I should not slap on a set of headers.
Depends on your risk tolerance. I think fuel choice matters more. AFAIK, there are still Bosses out there running with both.

The throttle response is so much better with the Red key.
Probably the main reason why I don’t want to give it up.

And the next question is can the "octane adjust" setting be checked to see what it is set to?
Since FR is only doing new tunes via the ProCal handheld units, I’m not sure if any of the dealers can read or modify the setting. Might want to ask the dealer that did your install.

You will learn more here by accident than elsewhere by design.
And I remembered that detail quite by accident...so it’s certainly true.
 

Fabman

Dances with Racecars
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Pleasanton: 1/2 way between Sonoma and Laguna Seca
I’ve seen these, but haven’t looked very closely as I already have the Xineering blip module wired on the TPS with their inline harness. Seems like trouble with 2 devices trying to manipulate signal there. The car had a BAMA tune on it when I first bought it, and throttle response on that tune was much crisper than AED’s, so I know it’s possible. I have learned one thing though - if Shaun doesn’t feel like doing it, there’s absolutely no sense asking again.
Yes, I thought the same thing when I saw it as I have an auto blip...BUT, if Shaun can tune that out it would be awesome.
 
Sounds like your looking for something like this:

I have no idea if this is worth a dang but I've seen it endorsed by people who I would think should know.

I would stay away from those PedalMax. It won't do anything as far as throttle response.
It just connect between the gas pedal and the ECU and don't change any of the mappings. It only tricks the computer to tell it that you pressed the gas pedal further.
Ex : if you press the gas pedal pedal 10%, it would tell the ECU that you pressed it 20% or more
 

Fabman

Dances with Racecars
6,519
8,155
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
I would stay away from those PedalMax. It won't do anything as far as throttle response.
It just connect between the gas pedal and the ECU and don't change any of the mappings. It only tricks the computer to tell it that you pressed the gas pedal further.
Ex : if you press the gas pedal pedal 10%, it would tell the ECU that you pressed it 20% or more
Yes it’s just changing the pedal ratio. The one thing I noticed in some of their propaganda was that it supposedly opens the throttle body more fully. It suggests that the stock setup only opens 90%. I don’t know if thats true but you can bet I’m going to be looking at that. Another thing it claims is that it eliminates throttle hang. Makes it more responsive. That I would be interested in. I’ll mention it to Shaun and get his opinion on it. Stay tuned.
 
1,246
1,243
In the V6L
Yes it’s just changing the pedal ratio. The one thing I noticed in some of their propaganda was that it supposedly opens the throttle body more fully. It suggests that the stock setup only opens 90%. I don’t know if thats true but you can bet I’m going to be looking at that. Another thing it claims is that it eliminates throttle hang. Makes it more responsive. That I would be interested in. I’ll mention it to Shaun and get his opinion on it. Stay tuned.
I did my own SCT calibrations on my supercharged 2011 Mustang GT, and you can improve the throttle response. There's a translation table from pedal position to "commanded torque" and this table is two-dimensional. You get a different pedal response curve depending on RPM and there's a second table that changes pedal response based on vehicle speed. The way Ford tunes these for street use, if you hold the pedal steady, commanded torque drops as the speed and RPM rise, presumably to improve fuel economy, but the sensation is that the throttle isn't responding and you have to keep pushing deeper and deeper to maintain the rate of acceleration. Just remapping these tables makes the engine feel more responsive. I actually made this change on my 2015 Explorer V6. Much nicer to drive with the tables cleaned up.
 

Mad Hatter

Gotta go Faster
5,237
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Santiago, Chile
Just a word of caution with the accererator. I loved the accelerator feel in my previous Race tune from Shaun.. But in the rain, the car was a serious hand full. Had to use one toe to accelerate and the tires spinning all the time. That was with TC completely off in the tune.
 
I have a 2014 Boss 302S race car that I bought new in September 2014. It's never been raced, just used for NASA TT and Shelby Club events. During about its 4th or 5th event, in July 2015, it blew its engine just like yours did. My car was new enough and I provided video like you have and data acquisition data to Ford Performance and I got a new stock Boss engine from them. In my failure analysis, I think either the #4 or #8 rod bearing siezed. The car companies use all-aluminum rod and crank bearings these days, and they don't have any forgiveness in them, like the old tri-metal bearings did. Car companies won't use tri-metal bearings anymore, because the babbit of the tri-metal contains lead. I told them that they advertised the 302S as a race and track day capable car, but they said that serious racers, which I am not, pull the engines and prep them with high durability parts, including tri-metal bearings. Before I installed the new engine, I installed tri-metal rod bearings with the special coating that the Nascar engine builders use for quick break-in. I think I bought the bearings from Roush, but they may be a standard option with Federal Mogul. I've run the car in many track events since then, and never had a problem. I've always run 98 octane race gas in the car, including when it blew up.
Incidentally, I had run my 2102 Laguna Seca Boss in track events from 2012 through most of 2014, or 3 years, and never had a problem with it. On the chassis dyno for NASA TT classing, the 302S put out about 50 Hp more than the street Boss, because the 302S runs a Ford Performance tune. I never modified either original engine in any way.
So a question for others who may have a lot more experience with these modular engines, if I am right on rod bearing siezure being the immediate cause of failure, why does every modular engine seem to blow on the back 2 cylinders? Because detonation causes higher rod bearing load? And would I have been having detonation with 98 octane gas?
If your using higher octane than what your tune requires then you won’t get better performance and your wasting money. If you use fuel with a lower octane rating than what your tune requires then you will certainly have detonating issues and you will most likely blow your motor.
 

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