The area of the huge single throttle dwarfs the new twin 65mm throttle body. Our feeling is that the old big-blade throttle body was so big that the ECU was getting confused by the airflow at certain percentages of throttle opening and the correct tables were not being adjusted correctly with previous tunes. Hence the weird non-linear throttle response, crazy idle and pissed off traction control. As an interesting side note, Ford Performance has discontinued the large single blade drive by wire version of their throttle (the mechanical throttle body version is still available). Probably everyone was having the same problem!Howard bolts up our new throttle body and snaps the connectors in place before reinstalling the intake pipe.Of course, being engineered by Ford, everything fit perfectly just as the old part did. Now it was time to tune. Even with no tuning, the cars’ idle and throttle response was immediately improved. It almost felt like a whole new car. Would tuning by a real expert make a difference?We drove our Mustang straight to Church Automotive Testing to see what could be done about our disappointing power output and lackluster bottom end.Church uses the Dynapack hub dyno system. A Dynapack’s power absorption units bolt directly to the cars drive hubs. Many people like to use this dyno type for tuning due to its slip free and smooth loading of the engine.
1) Regarding the ford racing (big oval) TB, are you saying that with even the smallest throttle input it was allowing two much air for the ECU to compensate, or was the poor running more a factor of the other tuners inability to map the ECU?
2) I guess this depends on your answer to the first question, but if the cause of the poor idle, lack of power, …etc was tuner based, why not go back to the bigger throttle body?
It baffles me how people can confidently take money to tune someone else’s car if they can’t even get the basics right. There’s no excuse on a modern engine with built-in knock detection to have a timing table advanced enough to cause knock. I understand the ECU in that mustang is much more complex than the Megasquirt in my Miata, but the basics of solid reference VE tables, timing, accel/decel enrichment and idle control are basic things that a tuner needs to know.
You’re missing the fact that there are multiple VE maps. GenIV GM small block V8 engines don’t even use VE maps. Instead there are a bunch of 2D tables. EFILive did come up with a GUI called virtual VE, so the tuner is able to treat the tune as though it had an actual VE map. You then allow EFILive to generate all the changes to the 2D tables and voila, car is tuned. I can’t imagine what the GenV stuff is like. Comparing standalones or even early OBDII computers to what’s out there now is apples and dog shit. I’m with you on the knock, that’s unacceptable, but I could totally see how everything else that was wrong could have easily been entirely due to outdated software like Mike said.
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Just a couple questions:
1) Regarding the ford racing (big oval) TB, are you saying that with even the smallest throttle input it was allowing two much air for the ECU to compensate, or was the poor running more a factor of the other tuners inability to map the ECU?
2) I guess this depends on your answer to the first question, but if the cause of the poor idle, lack of power, …etc was tuner based, why not go back to the bigger throttle body?
The throttle body is way too big for the size of the engine. Ford has even discontinued it.
It baffles me how people can confidently take money to tune someone else’s car if they can’t even get the basics right. There’s no excuse on a modern engine with built-in knock detection to have a timing table advanced enough to cause knock. I understand the ECU in that mustang is much more complex than the Megasquirt in my Miata, but the basics of solid reference VE tables, timing, accel/decel enrichment and idle control are basic things that a tuner needs to know.
You’re missing the fact that there are multiple VE maps. GenIV GM small block V8 engines don’t even use VE maps. Instead there are a bunch of 2D tables. EFILive did come up with a GUI called virtual VE, so the tuner is able to treat the tune as though it had an actual VE map. You then allow EFILive to generate all the changes to the 2D tables and voila, car is tuned. I can’t imagine what the GenV stuff is like. Comparing standalones or even early OBDII computers to what’s out there now is apples and dog shit. I’m with you on the knock, that’s unacceptable, but I could totally see how everything else that was wrong could have easily been entirely due to outdated software like Mike said.