The Test

[88Racing]

This next weekend june 4-6 is going to be the state soccer tourny in Rapid City. We will also be doing some sight seeing around in the Black Hills.

So why do I call it a test?
I will see how well the 87 perf tune holds out!

Also going to be hauling about 500 lbs extra in the bed. I got nominated to haul the coolers and other team gear. Thank goodness no trailer!


As far as:
Milage-whats the improvement?
Altitude change-going to be going from 1000-5000ft?
Tranny-how is it going to shift through the hills?
Gotta get with Bill before I go on the hiccup issue!
Basically let's see what/how the tune does in the mini mountains.

I know one thing hopefully the drive to Mount Rushmore will be more fun!

Maybe I should throw in Jack's settings in the custum option menu?

Lars

[88Racing]

Well the added power in the hills was impressive. It was 50-70 F up there so the cht stayed about 206-210. TFT never went over 160 F. The little extra pep really helps getting into traffic easier. The roads going to Mt Rushmore were fun but I totally respected the posted speed limit, being the "law" is all over up there!

Logged approx 800 miles round trip on the 87 custom perf tune.

Some down falls were:
Mpg's at 80 mph 13.34-13.95
Thought the custom would do better than stock 14.5-15.75 mpg.

Every once in about 2 miles started to feel a pull in the motor. No it wasn't the compressor kicking in and out. Had it turned off.

A new problem arose. When hitting set on cc, started to get shudder in tranny.
I did raise the tq tip in +5 mph and this did not help the coast shudder. Also the 40-50 mph hiccup did not go away it's still there.
At some points during the trip it felt that the truck's nose was being pushed down and was being pulled from behind at the same time.

Lars

[88Racing]

Well just got off the phone with Bill and the general idea is try the custom tow tune. If I still have the same problem then I may need a HEX code update or in the mean time he is also looking into the open loop part of the file. It also puzzles him that I had no problems with the 93 canned tune.

But he has his hands full with trouble shooting some of the 08's right now.(Deal with these guys first Bill!)

So he also suggested some other options to try.

I will keep you guys posted.

Lars

[Jackpine]

This is SO strange! You have nearly the same truck as me, and with UD pulleys, you ought to get better mileage. I get about 15.5 at 70-75 and I never got that much before the custom tunes. I have the 200#+ bed cap that sticks up about 6 inches above the cab, so it adds wind resistance, as well as weight.

I NEVER feel any "drag" on the motor, and here in Arizona, the climate control is ON - all the time!

I WILL say, and I almost hate to bring it up, but hot temperatures are better for fuel economy than cold ones. And, it's not due to the blend of gasoline. It has to do with the A/F mixture and the fact that cold air is more dense, needing more fuel to maintain stochastic (which is controlled by feedback from the O2 sensors in closed loop). Anytime you run in hot temps or at high altitudes, you should expect a loss of power, but an increase in fuel economy.

This simple fact is why aircraft fly at high altitudes when traveling long distances, whether they are jet or recip powered. (For short distances, the climb to altitude is such a gas guzzler that they stay low).

And, going back to your first post, which I somehow missed before this, I DID reduce part throttle upshift and downshift speeds by the max to get my truck into higher gear sooner and I did the same with the TC lock/unlock points (trying to keep the TC locked as long as possible). All this was in the name of trying to keep the transmission from downshifting/unlocking when it felt like there was still power to spare. You could always try this - I don't see how it could hurt.

- Jack

[88Racing]

Jack worst case scenario is getting the truck reflashed to the current most updated HEX code. Bill informed me that Ford already is already on the 5th update for this HEX. Mine being the first version. Why do I say worst case?
I will have to tell a fib and Bill will have to rewrite the tunes.

Lars

[Jackpine]

Yowtch! I really don't mind the fib to Ford, after all, they DO need to put out a good product, but bummer that Bill will have to rewrite the tunes.

I wonder if he has to do it all from "scratch" or if he can just modify what he already has somehow? My semi-intelligent guess is, he has to start over at the beginning, since I'm sure different HEX codes mean different baseline properties.

- Jack

[88Racing]

I am supposed to try all the other things also and log the resultants. So he can get a base line of what's going on. I also told him that this may take a week or 2 on my end since the truck is not a DD. Wish I could sell or unload 24 gallons of 87oct and put 92oct in to try the 93 canned perf tune again. I was just going from memory when talking to him yesterday. Hopefully the reflash isn't needed and only tweeks to the open loop, only have to be done.

Lars

[88Racing]

Ok

Loaded the 87 perf tow tune last night and also the CO settings.
No more hiccup at 40-50 mph.
The economy meter went up 2 mpg.
Did not go over 70 mph at any time, it was only a short drive.
Guess what?
CC shudder is still there.
Still feel a pull or a drag with the motor.
The shudder is shorter duration and paddlelock doesn't flash on and off.
Bill what are we going to do?

Lars

[88Racing]

Something else I noticed. Under heavy acceleration the economy goes up by .4-3.0 mpg. This is happening in both custom tunes. In stock its just the opposite.

Lars

[Jackpine]

Originally Posted by 88Racing

Something else I noticed. Under heavy acceleration the economy goes up by .4-3.0 mpg. This is happening in both custom tunes. In stock its just the opposite.

Lars

Good grief! That makes no sense at all! You're talking about instantaneous economy, right? I know when I monitored mine (for a short time), anytime I stepped on the gas, it dropped and when I backed off, it went up.

Your PCM sounds really confused.

- Jack