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View Full Version : Throttle position confuddlement


turboberserker
February 21st, 2006, 04:28 AM
When should the reported TP be 0%? Mine *never* is... The lowest I've ever seen it was today at 13%. Normally, foot off the pedal is 16-18%. This seems weird to me...
Black02SS
February 21st, 2006, 04:34 AM
You have electronic throttle and probably will never see 0 except when the truck is off.
turboberserker
February 21st, 2006, 04:43 AM
I do have DBW throttle electronics. Seems like such a waste of good bandwidth ;)

Since I have the commercial version, can't I just tweak the throttle voltages?
GMPX
February 21st, 2006, 09:27 AM
It's normal, ignore it and move on :-)

Cheers,
Ross
turboberserker
February 21st, 2006, 01:47 PM
It's normal, ignore it and move on :-)

Cheers,
Ross

Hehe what fun is that :P

:thankyou2:
TunasTwins
January 23rd, 2010, 06:04 PM
Back from the dead....Does RAFIG tuning still apply to DBW? If so anything worth mentioning? I logged my STIS and LTIT and made the changes based on the average correction at each temp break point. Is this all useless with DBW?
DrX
February 6th, 2010, 06:31 AM
Back from the dead....Does RAFIG tuning still apply to DBW? If so anything worth mentioning? I logged my STIS and LTIT and made the changes based on the average correction at each temp break point. Is this all useless with DBW?

It still applies. The difference is that the idle air is controlled by the throttle blade rather than an IAC valve. For best results, B4349 must also be set according to the throttle size if the throttle has been upgraded to a larger size.

On my 5.3 idle throttle was something like 7%. IIRC it is around 12% on the 427. These numbers are with 90mm TBs.
twadam
June 1st, 2010, 02:06 AM
It still applies. The difference is that the idle air is controlled by the throttle blade rather than an IAC valve. For best results, B4349 must also be set according to the throttle size if the throttle has been upgraded to a larger size.
On my 5.3 idle throttle was something like 7%. IIRC it is around 12% on the 427. These numbers are with 90mm TBs.

Is simply reducing the value of B4349 by the TB's surface area diff's in percentage correct ? (ie., changing from a single blade 80mm to twin 58mm)
Let's assume the factory tune I'm using was for a car with an 80mm TB.
Surface Area of single blade 80mm = (3.14*40*40) = 5024
Surface Area of twin blade 58mm = (3.14*29*29)*2 = 5281
Percentage Diff. is basically a 5% increase in surface area.
So would you decrease B4349 by 5% to compensate for the 58mm TB ?
DrX
June 1st, 2010, 03:07 AM
Is simply reducing the value of B4349 by the TB's surface area diff's in percentage correct ? (ie., changing from a single blade 80mm to twin 58mm)
Let's assume the factory tune I'm using was for a car with an 80mm TB.
Surface Area of single blade 80mm = (3.14*40*40) = 5024
Surface Area of twin blade 58mm = (3.14*29*29)*2 = 5281
Percentage Diff. is basically a 5% increase in surface area.
So would you decrease B4349 by 5% to compensate for the 58mm TB ?

B4349= 100/throttle area
twadam
June 1st, 2010, 03:18 AM
B4349= 100/throttle area

Great! Thanks.
voda1
June 2nd, 2010, 06:18 AM
You have electronic throttle and probably will never see 0 except when the truck is off.

hQuick wrote in another thread that for a filter he sets TPS less than 0.5%(to remove decel). Any suggestions for a value with DBW system. Doing AutoVE by the way.