New PHP chip, wanting opinions please.

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Mar 8, 2013 | 10:20 PM

#16

Texas Chain Ring

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Quote:

Originally Posted by cleatus12r

Arbitrary numbers (since I'm on "the internet computer" and not on one of the two "work computers" and there's no sense in powering up either one for this example):

Vehicle Speed------Torque Output

88 MPH ----------100%
90 MPH ----------50%
92 MPH ----------30%
Anything more----0%

Vehicle speed is an input to the PCM and the PCM calculates torque output. The 7.3L in the 99-03 trucks doesn't "shut off". It just makes less power until the vehicle reaches terminal velocity.

in that case a stock truck should be able to hit 100 or will it run out of torque before then? Someone said 92 mph was terminal velocity yet you're saying at 92 there is still 30% left even at least in deleting increments of percentage to give which means more speed. It sure felt like there was much left when I was at 100mph. And how does a chip re-arrange it so those percentages of those numbers have no detriment on the terminal velocity, or does a chip/tune just override the pcm completely? That can't be right, can it? I had to ask.

and nice explanation, btw.

Mar 8, 2013 | 10:30 PM

#17

Texas Chain Ring

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sorry Cleatus, I may be wording myself wrong. Does a chip change that speed to left available torque percentage ratio and how? Does that make sense?

Mar 8, 2013 | 10:30 PM

#18

cleatus12r

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Joined: Apr 2004

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From: Reed Point, MT

Quote:

Originally Posted by Texas Chain Ring

in that case a stock truck should be able to hit 100 or will it run out of torque before then?

Ask anybody who just has to drive that ridiculously fast....
Do some searching on the internet and find out how much power it actually takes to keep an 8,000 lb. brick moving at 92 MPH.

Quote:

Someone said 92 mph was terminal velocity yet you're saying at 92 there is still 30% left even at least in deleting increments of percentage to give which means more speed.

See above answer. Just for argument's sake, use a calculator and figure out what 30% of 500 is. Here's a hint: It's not very much compared to what you'll find after reading the first reply. Next, convert that torque value to horsepower and find out how much power that is potentially being made at 90 MPH. Keep in mind that the actual torque output of the engine isn't anywhere near 500 ft. lbs. at speeds above 2500 RPM.

Quote:

And how does a chip re-arrange it so those percentages of those numbers have no detriment on the terminal velocity, or does a chip/tune just override the pcm completely? That can't be right, can it?

Yes, the chip overrides the operational data already in PCM from which the truck runs. Although it's not rocket science and everybody who sells tuning knows how to get rid of that pesky speed limiter, I'll leave it to your imagination.