Anyone tried a cable controlled throttle on a e-throttle ecm?

[csracing]

I've got a 2007 Mustang GT that I'm converting to a racecar. I have a 305" 3-valve engine that I built and I'd like to eliminate the e-throttle on for simplification. Has anyone ever tried this on the stock ECU? Just thought I'd ask before I go standalone.

[Montecarlodrag]

Yes and it doesn't work. Stock PCM was not designed to run in throttle-follower mode, it gives erratic results.
What is the issue you have? I find the electronic throttle on fords to be very reliable.

[csracing]

Yes and it doesn't work. Stock PCM was not designed to run in throttle-follower mode, it gives erratic results.
What is the issue you have? I find the electronic throttle on fords to be very reliable.

Doesn't work when using the stock throttle pedal or doesn't work when you use a true TPS sensor as the input?

My engine is pretty unique and a far cry from what the stock ECU was intended to manage. Big cams, heavy springs, VCT eliminated, high compression, extensive port work on the heads, etc have all contributed to the tuning challenges. Idle has been my biggest struggle, but inconsistency on fueling has also been off. I intend to drag race the car and need it to idle and take full throttle with little in between. Standalone with live tuning capabilities is very alluring.

[Eric@HPTuners]

Should be no issue tuning the combo with ETC, but the ETC PCM has no provision to control an IAC, so if you are set on going to a cable throttle you will need to go to a standalone product.

[Montecarlodrag]

Doesn't work when using the stock throttle pedal or doesn't work when you use a true TPS sensor as the input?

Both.
As Eric said, the stock PCM can't control idle for a cable TB using IAC. You lose idle control and get stalling and surging, this is going to make your idle problems worse.
You also lose the Torque Model and the PCM does all kinds of strange things.

I only tried it once to install a cable TB with TPS but soon reverted back to stock. It's very difficult to trick the PCM to not go into reduced power, the worse thing is that the TPS never reads correctly because you need to use two sensors to satisfy the PCM. I got all kinds of backfires, hesitation etc. and was unable to fix them with fuel/spark. A carb works better.

I think your combo can be tuned with the stock PCM/Pedal/TB. As long as you aren't flowing massive amounts of air and the MAF, TB aren't maxed out in the OS, you should be able to fix it.
If you still think a cable TB is the solution, go with an aftermarket controller, they work good and all of them have real time tuning.