Roush go BOOM!
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From: North Canton, Ohio
Originally Posted by FordgasmSC86
Alright guys. Let me start out by telling you a brief bit about myself. I used to be a mechanic for Ford. I was ASE certified, but before I could get my Master certifications I decided to quit wrenching(3 months ago) for it was not the career for me, more or less a hobby. I worked at, Kelly Ford in Melbourne, FL. At Kelly, I have had the experience to install a Roush supercharger on a 5.4L King Rancher. Not a bad install. The guy that owned the truck, some engineer, also installed high flow cats, long tube headers, high flow intake, Borla catback exhaust, and instead of having his PCM flashed by Ford, or sent out to Roush, he went to a local speed shop and had it dyno tuned. This was in 2006 and I continued to maintain his truck until I left the dealership. He had no problems...the truck was beautiful, was very fast on 20" rims 36" tires, not to mention it's boner popping tone. My guess with your truck, "Roush LT", is that it was not caused by a rich mixture. That would actually cause you truck's combustion chamber to be quenched and run cooler, thus sacrificing about 10-15% of your power. Without the proper tune, probably because Lincoln deleted the Roush tune, it sounds as if your truck went lean. Your stock tune was not providing your supercharged engine with a sufficient amount of fuel. It should be around 13.1:1(performance) or 14.7:1(economy). This lean mixture increased Knox and Hydrocarbons to such a degree, that your catalytic converter probably was overwhelmed, and thus melted. This "clog" caused an enormous amount of back-pressure, and well, it's only as strong as the weakest link. If you had stock exhaust or small 2.5" exhaust pipes, that probably didn't help either. That's what I think happened. Tell that to your lawyer and mechanic, and see what they say. It's Lincoln's fault in my eyes. I hope what I have said helped. If you decide to get your motor replaced, I recommend what the engineer did. Also, I would invest in a boost gauge, A/F gauge, exhaust temp. gauge, and maybe even a tranny temp. gauge with cooler. These things will at least warn you before a problem, so your wife doesn't have to see that disappointing look on your face 
as well hers when she sees what a new setup is going to cost
. Have a good one, and good luck. 
as well hers when she sees what a new setup is going to cost . Have a good one, and good luck. 13:1 and 14.7:1 is far too lean for a SC'd engine in one of these trucks !!!! I don't care who you worked for or what certifications you have....dangerously lean....
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13:1 is rich not lean 14.7 is perfect
Originally Posted by Marc Carpenter
13:1 and 14.7:1 is far too lean for a SC'd engine in one of these trucks !!!! I don't care who you worked for or what certifications you have....dangerously lean....
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From: Anaheim, Ca.
Originally Posted by Marc Carpenter
13:1 and 14.7:1 is far too lean for a SC'd engine in one of these trucks !!!! I don't care who you worked for or what certifications you have....dangerously lean....
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A mixture is the working point that modern engine management systems employing fuel injection attempt to achieve in light load cruise situations. For gasoline fuel, the stoichiometric air/fuel mixture is approximately 14.7 times the mass of air to fuel. Any mixture less than 14.7 to 1 is considered to be a rich mixture, any more than 14.7 to 1 is a lean mixture - given perfect (ideal) "test" fuel (gasoline consisting of solely n-heptane and iso-octane). In reality, most fuels consist of a combination of heptane, octane, a handful of other alkanes, plus additives including detergents, and possibly oxygenators such as MTBE (Methyl tertiary-butyl ether) or ethanol/methanol. These compounds all alter the stoichiometric ratio, with most of the additives pushing the ratio downward (oxygenators bring extra oxygen to the combustion event in liquid form that is released at time of combustions; for MTBE-laden fuel, a stoichiometric ratio can be as low as 14.1:1). Vehicles using an oxygen sensor(s) or other feedback-loop to control fuel to air ratios (usually by controlling fuel volume) will usually compensate automatically for this change in the fuel's stoichiometric rate by measuring the exhaust gas composition, while vehicles without such controls (such as most motorcycles, and cars predating the mid-1970's) may have difficulties running certain boutique blends of fuels (esp. winter fuels used in some areas) and may need to be rejetted (or otherwise have the fueling ratios altered) to compensate for special boutique fuel mixes. Vehicle manufacturers do not provide a means of altering predefined fuel maps making such alterations impossible without replacing the stock ECU with a customizable system. Vehicles using oxygen sensors enable the air-fuel ratio to be monitored by means of an air fuel ratio meter.
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From: Odenton MD
Originally Posted by Marc Carpenter
13:1 and 14.7:1 is far too lean for a SC'd engine in one of these trucks !!!! I don't care who you worked for or what certifications you have....dangerously lean....
This guy been a part of hundreds of tunes I would take his word on it
X3
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Originally Posted by wicked0ne
13:1 is rich not lean 14.7 is perfect
Simply - he is referring to Open Loop operation; ( ~ approx 70% LOAD and up to actual WOT).
Under those conditions, 13:1 --->15:1 ---> and up, is TOO LEAN for an S/C application.
Your paragraph above is only relevant in Closed Loop, where Stioic is maintained by O2 feedback. Light loads, part throttle.
But - yer the same guy who thinks the stock Roush tune is a good one. It's not - it's crap. Safe, perhaps, but crap. Sorry.
You need to read this for an eye-opener: http://www.ford-trucks.com/article/i...rformance.html
Do your homework before you grenade yer engine.
MGD
Last edited by MGDfan; Nov 13, 2007 at 12:09 AM.
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From: Odenton MD
Originally Posted by MGDfan
Sorry pal... yer wrong and Marc's right. You have gaps in your understanding.
Simply - he is referring to Open Loop operation; ( ~ approx 70% LOAD and up to actual WOT).
Under those conditions, 13:1 --->15:1 ---> and up, is TOO LEAN for an S/C application.
Your paragraph above is only relevant in Closed Loop, where Stioic is maintained by O2 feedback. Light loads, part throttle.
But - yer the same guy who thinks the stock Roush tune is a good one. It's not - it's crap. Safe, perhaps, but crap. Sorry.
You need to read this for an eye-opener: http://www.ford-trucks.com/article/i...rformance.html
Do your homework before you grenade yer engine.
MGD
Simply - he is referring to Open Loop operation; ( ~ approx 70% LOAD and up to actual WOT).
Under those conditions, 13:1 --->15:1 ---> and up, is TOO LEAN for an S/C application.
Your paragraph above is only relevant in Closed Loop, where Stioic is maintained by O2 feedback. Light loads, part throttle.
But - yer the same guy who thinks the stock Roush tune is a good one. It's not - it's crap. Safe, perhaps, but crap. Sorry.
You need to read this for an eye-opener: http://www.ford-trucks.com/article/i...rformance.html
Do your homework before you grenade yer engine.
MGD
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I wasn't talking about WOT or 70% laod. I was just making a gereral statement on A/F ratios. At WOT throttle my truck is at 12.2 which is good to me. I think it's all in the application for me the Roush tune is good ( I'm waiting on my Troyer tunes but probably will not leave them installed all the time) . I have a 10 in lift with 37in tires abtou to go 40in. It is not a race truck only more power when you need it off road. In my case conserative is best.
Originally Posted by MGDfan
Sorry pal... yer wrong and Marc's right. You have gaps in your understanding.
Simply - he is referring to Open Loop operation; ( ~ approx 70% LOAD and up to actual WOT).
Under those conditions, 13:1 --->15:1 ---> and up, is TOO LEAN for an S/C application.
Your paragraph above is only relevant in Closed Loop, where Stioic is maintained by O2 feedback. Light loads, part throttle.
But - yer the same guy who thinks the stock Roush tune is a good one. It's not - it's crap. Safe, perhaps, but crap. Sorry.
You need to read this for an eye-opener: http://www.ford-trucks.com/article/i...rformance.html
Do your homework before you grenade yer engine.
MGD
Simply - he is referring to Open Loop operation; ( ~ approx 70% LOAD and up to actual WOT).
Under those conditions, 13:1 --->15:1 ---> and up, is TOO LEAN for an S/C application.
Your paragraph above is only relevant in Closed Loop, where Stioic is maintained by O2 feedback. Light loads, part throttle.
But - yer the same guy who thinks the stock Roush tune is a good one. It's not - it's crap. Safe, perhaps, but crap. Sorry.
You need to read this for an eye-opener: http://www.ford-trucks.com/article/i...rformance.html
Do your homework before you grenade yer engine.
MGD
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Joined: Feb 2004
Posts: 10,390
Likes: 10
Originally Posted by wicked0ne
I wasn't talking about WOT or 70% laod. I was just making a gereral statement on A/F ratios. At WOT throttle my truck is at 12.2 which is good to me. I think it's all in the application for me the Roush tune is good ( I'm waiting on my Troyer tunes but probably will not leave them installed all the time) . I have a 10 in lift with 37in tires abtou to go 40in. It is not a race truck only more power when you need it off road. In my case conserative is best.
Sorry, your post didn't come across that way, which is what elicited those responses. Thanks for the clarification., lol.
TP's tunes are still safe, no worries there - Roush's are CYA tunes, and cripple the hardware's potential far too much - really fek's up that ol' value equation, lol.
Good luck!
MGD
Last edited by MGDfan; Nov 13, 2007 at 09:04 AM.
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It's all good I'm waiting on my S/C to come back from Steigmeir. MGD do you think the reason I'm getting a 18+ A/F reading at idle is because of how close I had to weld in my bung before the drive side cat. (Because I wanted it before the CAT) Right when I bring my idle up to 800 to 900 RPM it stays around 14.7. I wasn't able to follow AEM instructions and weld it in atleast 18 in fron exhaust ports. It's right bedie the first stock O2 sensor. It's more like 9in from rear exhaust port.
I'm waiting on my S/C to come back from Steigmeir. MGD do you think the reason I'm getting a 18+ A/F reading at idle is because of how close I had to weld in my bung before the drive side cat. (Because I wanted it before the CAT) Right when I bring my idle up to 800 to 900 RPM it stays around 14.7. I wasn't able to follow AEM instructions and weld it in atleast 18 in fron exhaust ports. It's right bedie the first stock O2 sensor. It's more like 9in from rear exhaust port.
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Joined: Feb 2004
Posts: 10,390
Likes: 10
Originally Posted by wicked0ne
It's all good I'm waiting on my S/C to come back from Steigmeir. MGD do you think the reason I'm getting a 18+ A/F reading at idle is because of how close I had to weld in my bung before the drive side cat. (Because I wanted it before the CAT) Right when I bring my idle up to 800 to 900 RPM it stays around 14.7. I wasn't able to follow AEM instructions and weld it in atleast 18 in fron exhaust ports. It's right bedie the first stock O2 sensor. It's more like 9in from rear exhaust port.
I'm waiting on my S/C to come back from Steigmeir. MGD do you think the reason I'm getting a 18+ A/F reading at idle is because of how close I had to weld in my bung before the drive side cat. (Because I wanted it before the CAT) Right when I bring my idle up to 800 to 900 RPM it stays around 14.7. I wasn't able to follow AEM instructions and weld it in atleast 18 in fron exhaust ports. It's right bedie the first stock O2 sensor. It's more like 9in from rear exhaust port.One is an 'extender' if there is room ( I saw a post on that -- I think Jbrew, bless him, knows about this stuff). This gets the sensor head out of the immediate exhaust stream - it *may* help.
Second, is a copper heat shield for the sensor. Instructions for that and perhaps some other stuff you may find useful, is on Innovate's site.
http://www.innovatemotorsports.com/support.php Dig around in the LM-1 manual or the LC-1 manual for details.
Lastly you can ask this Q in either innovate's forum, or AEM's (if they have one).
Good luck.
MGD
