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

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PatientZero

@restless_performance
825
865
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Autocross
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10-20 Years
Kansas City, Missouri
Historically I have felt this way as well about octane boosters, however this Torco fuel accelerator is a different animal. This has worked extremely well to boost the crappy 91 octane here in CA. I’ve tried blending 100 octane race gas at the the track with pump gas, only to fight random misfire codes. Hard to tell how fresh the fuel at the track is, and at least with the Torco I know what I have no matter which track I’m running at.

https://torcoracefuel.net/products/torco-accelerator

View attachment 58802

Torco is one I've heard that actually works from people smarter than me. I should rephrase and say MOST don't work and race fuel is the better alternative. Not hard to find a VP or Sunoco dealer and buy 5 gal to take with you to the track. Just my .02.
 

OFisherJr

2013 Boss 302 #0060
Well I blew up my motor on my 4th track day this year. Does anyone have some insight as to why?
Here are the details:
Stock motor with 11,000 miles, no cats, X-pipe into Borla mufflers, washable air filter in stock airbox, Sebra 72 row oil cooler, fresh oil, Ford Track Key, 91 octane non-oxygenated gas
Number 8 piston is exploded and the rod with no cap on it is wedged in the area between the heads
Number 4 piston is still in the cylinder and 1/2 the rod is still connected to the crankshaft
Two big holes in the block on either side
Motor is still in the car until next week.
Bigger question - how do I prevent it from happening again?

View attachment 58601
Really sorry to hear this. My engine, air intake and exhaust are all stock. I run 93 octane, and Amsoil Signature 5w-50 oil. Have 33k miles on her and done 4 or 5 HPDE events and no issues.

With your mods did you go to larger injectors and/or get it tuned on a dyno by a reputable mechanic? I’m wondering if it was running lean and suffering detonation which put extra stress on the engine.
 
Historically I have felt this way as well about octane boosters, however this Torco fuel accelerator is a different animal. This has worked extremely well to boost the crappy 91 octane here in CA. I’ve tried blending 100 octane race gas at the the track with pump gas, only to fight random misfire codes. Hard to tell how fresh the fuel at the track is, and at least with the Torco I know what I have no matter which track I’m running at.

https://torcoracefuel.net/products/torco-accelerator

View attachment 58802
Thanks, ordered 4.....mixing this with 10 gallons of 93 will save me $60 at the track Using 104
 

Dave_W

Cones - not just for ice cream
986
1,278
Exp. Type
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20+ Years
Connecticut
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.

Found some interesting articles that go into more detail on aluminum-silicon alloy bi-metal vs copper/lead tri-metal bearings.

Clevite/Mahle and King both make non-coated and coated tri-metal main bearings for the Coyote. Clevite has tri-metal rod bearings as well. King shows Mod motor rod bearings for the 4.6/5.2 but not Coyote, even though I beleive the rod journal is the same size - could just be they haven't updated their info. Looks like both Clevite & King rod bearings are "narrow" to fit larger journal fillets; not sure if that makes a difference for use on the stock crank.

So after reading those articles, I'm thinking that anyone wanting to push their car hard on track more than drive it on the street, or especially with a dedicated track car, should be using tri-metal bearings, with the understanding that they won't go 200k miles like a bi-metal. Question I have is, can you change the main & rod bearings from below without having to take the heads off?
 

Grant 302

basic and well known psychic
Question I have is, can you change the main & rod bearings from below without having to take the heads off?
Physically, yes. But practically, no...or perhaps just shouldn’t. I mean, how are you going to measure and check clearances and such?

I’ve never worked on the bottom of any V arrangement, but on a stand or bench and upside down.

Anyway, I’m curious what specific info you read to ‘conclude’ it’s better to use the tri-metal.
 
6,363
8,191
Well, fuel is something I don't mess with.. actually, I used to mess with it in karts, I had a friend who was a chemist at shell Oil company and you can cheater up fuel quite a bit, although I never ran cheater fuel (or raced the meter as it was called) I did run the stuff on test days and in practice, and then let the other guys get caught cheating while I ran legal. A lot of additives, at least the ones that work, are serious carcinogens, and you don't want to be anywhere around them. Just run the legit track gas and call it a day. The addition of E85 (or E97, or E anything) is not a substitute for good fuel. One of the ways octane is measured is it's resistance to knock, adding ethanol or methanol does increase the fuel's resistance to knock,, but it does it "artificially" in that it forces the fuel to burn slower, this does not really produce more power as far as we are concerned, unless the car is tuned to run it.
and no, I'm not going to pass on ways to cheater up your fuel.
 

Fabman

Dances with Racecars
6,519
8,156
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W2W Racing
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Pleasanton: 1/2 way between Sonoma and Laguna Seca
Well, fuel is something I don't mess with.. actually, I used to mess with it in karts, I had a friend who was a chemist at shell Oil company and you can cheater up fuel quite a bit, although I never ran cheater fuel (or raced the meter as it was called) I did run the stuff on test days and in practice, and then let the other guys get caught cheating while I ran legal. A lot of additives, at least the ones that work, are serious carcinogens, and you don't want to be anywhere around them. Just run the legit track gas and call it a day. The addition of E85 (or E97, or E anything) is not a substitute for good fuel. One of the ways octane is measured is it's resistance to knock, adding ethanol or methanol does increase the fuel's resistance to knock,, but it does it "artificially" in that it forces the fuel to burn slower, this does not really produce more power as far as we are concerned, unless the car is tuned to run it.
and no, I'm not going to pass on ways to cheater up your fuel.
Propylene oxide was super common back in the day. You could always tell who was running it because it produced a brown flame out of the exhaust. At first one car, then a few, then most of the field had brown flames. It was illegal, specifically called out as an additive and not permitted. I don't cheat so I didn't run it. But what I did do was ask what specifically the rule was, what was considered an additive and how did they check for it. They said they put a strip of paper in the fuel and if it changes color its illegal and if it doesn't its legal. I made them repeat that twice. I then ordered a thing called "Stealth" by Klotz fuels which also was oxygen bearing but didn't turn the paper colors and by the rules they gave me, I considered it legal. Sometimes you have to fight fire with fire. An unusual byproduct was that the stealth had an unusual smell when burned. Nobody ever could figure out why my car smelled like soap. LOL.
 
6,363
8,191
I've run Klotz in my 2 strokes, the WKA used Klotz as a criteria for their fuel. If you didn't run Klotz, you were slow, I can't believe they pulled that off. I had a fuel checker that some guy borrowed, it never worked again..lol
 

Fabman

Dances with Racecars
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Exp. Type
W2W Racing
Exp. Level
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Pleasanton: 1/2 way between Sonoma and Laguna Seca
I've run Klotz in my 2 strokes, the WKA used Klotz as a criteria for their fuel. If you didn't run Klotz, you were slow, I can't believe they pulled that off. I had a fuel checker that some guy borrowed, it never worked again..lol

I don't remember anybody ever having their fuel checked....except me. And I passed.
 

Dave_W

Cones - not just for ice cream
986
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Connecticut
Physically, yes. But practically, no...or perhaps just shouldn’t. I mean, how are you going to measure and check clearances and such?
I was thinking of removing the engine to make it easier to do other work - headers, oil pump, crank sprocket, baffled oil pan. I just didn't want to take the heads off if I didn't need to.

Anyway, I’m curious what specific info you read to ‘conclude’ it’s better to use the tri-metal.
I got interested and tried to read up on the topic. Could be that I just found a bunch of marketing, but I did include 3 links. The takeaway I got was that aluminum-silicon alloy bi-metal bearings have a much harder surface than lead/tin/copper tri-metal bearings. This is good for long-wear durability in street engines where there isn't a high load at high rpm on the bearings. The silicon can even polish cast iron journals. Bi-metal can also be good for very high loads for short duration, like drag racing where you replace the bearings after each run. Bi-metal can also resist damage from "dirt" in the oil better than the tri-metal (supporting the longer oil drain intervals being specified by manufacturers), though the softer tri-metal has better "embedability" to absorb particles. The downside to bi-metal occurs in long-duration high-rpm high-load conditions where the hydrodynamic oil film can break down for short periods. The tri-metal bearings provide better "seizure resistance" by the babbit having a higher lubricity, and in extreme cases letting the crank journal deform some of the babbit layer. On the other hand, if the crank journal contacts the aluminum in a bi-metal bearing, it will start to microweld, pulling the face material off the bearing. The bit of bearing material welded to the journal then digs off more bearing face, and you end up "wiping the bearing." The bi-metal bearings designed for drag racing have higher percentages of silicon to try to reduce the microwelding and also "clean up" the journal face.

Anyway, like I said, it could all be marketing spin.
 

Grant 302

basic and well known psychic
I thought you meant doing engine work in the car. I understand leaving the heads on to ‘save’ on head bolt and other consumables, but I also see that as an opportunity to clean things up. Just for the price of a head change kit.

I got interested and tried to read up on the topic. Could be that I just found a bunch of marketing, but I did include 3 links.
Yes, but the three links are essentially the same guys saying almost the exact same thing. Pretty sure some of the text is cut n paste. I think you have it right here:
Anyway, like I said, it could all be marketing spin.

#s 4&8 are prone to failure due to heat. So they will usually be the ones to ‘find’ the operating limits of the engine. They are the last pair to get coolant flow, and oil flow. Bearing contact events happen more often as temps go up and they are simply more likely to happen at the back. Bearing failure is more of a symptom than a cause. This is why people have trouble ‘diagnosing’ the problem, which is heat. In the pistons, the problem is two fold. As the piston gets hotter it expands more than the bore. This reduces clearances heats up the oil film more and ultimately show up as more friction in the back cylinders. Now wether the increased friction here causes piston seize, burn or forces that cause contact at the main or con rod bearings is, to me at least, somewhat irrelevant. Problems that do happen to show up at the main bearing are also because the main galley feeds this bearing last. So if the oil is hot and the viscosity low it’ll make contact more often.

This is why I try to emphasize cooling the oil more and the pistons with cooling jets, and things like choosing the right oil for the intended use.
 
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Grant 302

basic and well known psychic
Plus, as Grant says, the track key is on the lean side.
Actually, I don’t think I’ve ever said that. To clarify, I don’t know that TracKey commands a leaner A/F ratio. It does, however, affect spark advance. A lot.

The thing I remember and one of the details about TracKey that seems to get overlooked is that there’s a toggle for ‘Octane Adjust’ when it’s being loaded. It’s my opinion that if you live in a 91 Octane state/area that you definitely need to have this set to ‘ON’. Otherwise, you need to use the silver key anytime there is less than 93 octane equivalent in the car. Even on the street.

I believe this is one of the issues contributing to Boss engine failures while using TracKey. And likely a contributing factor for the OP.

...

I also want to mention that the same is true for the FP/FRPP ProCal tunes regarding the Octane Adjust. For anyone in the future who may be searching for info on it.
 

Grant 302

basic and well known psychic
Ok, thanks for correcting that, I never could get me red key setup so I missed that adventure.
It’s not a big deal, just jogged my memory about the Octane Adjust setting is all.

And yeah, it’s unfortunate that you didn’t get to experience the Red Key...best part IMO is the throttle mapping for heel-toe down shifting. AFAIK, there’s still no aftermarket tuner who makes similar adjustments. It’s also why I’ve stuck with the ProCal tune for the GT.
 
1,163
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SoCal
AFAIK, there’s still no aftermarket tuner who makes similar adjustments. It’s also why I’ve stuck with the ProCal tune for the GT.

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.
 

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