idle RPM's Should I ask BAMA?

[beetlug]

Just out of curiosity I decided to lower my 2008 v(sucks) mustangs' idle RPM's. BAMA performance had set the idle at 750 RPM's. So I used my Intune device to "adjust parameters" and set the neutral idle at 650 and the drive at 650 RPM's. Flashed just fine and dandy. SO I went to go drive away afterwards and I could not get past approximately 1500 RPM's ! WOWZA! I could not speed up lol Every time I hit the gas I would get a slight surge to about 1500 RPM's only to watch the tachometer quickly go down to 650 RPM's! So I reloaded my custom Bama tune and was fine. Now my question is; Why would changing(lowering) the idle RPM's cause the lack of acceleration, or rather prevent any acceleration at all?

[mikel]

did you make any other changes when you did this?

[beetlug]

I don't think so, I did go into other menus just to look at other adjustable parameters. Pretty sure I backed out of all the other menus and confirmed no change. The only thing I can hypothesize is that the Drive Idle RPM's may be the issue. Why would there be two Idle RPM adjustments? One for drive, and one for Nuetral. As my Automobile is an automatic, the transmission keeps the engine from stalling when there is no push from the driver(I think the torque converter does this). BUT! If the drive idle was already set at 750 RPM's then changing that should not be the issue. I'm stumped.
Thanx for the reply btw

[beetlug]

HMMMmmmm, okay I tried it again and this time I had success
BUT! Where did the tire revolutions per mile go?
My speedometer is a little off despite the fact that Im using a custom Bama tune.

[mikel]

it should let you enter the sidewall numbes or height in inches if the tool is up to date, no more doing math to determine revs per mile

[beetlug]

Ah, yes it does. But my speedo is off by about 5mph. When I could change the revs per mile, I could get the speedometer to be exact. My method includes going by one of those "your speed" speed limit signs and an app called DigiHUD, and then some trial and error till I got it right. Which leads me to believe I should contact Bama Performance.

[mikel]

OK, try moving the height in inches to get it where you need, or ask Bama to set the correct rev per mile in your tunes