Ford gas V-10, speed limiter vs. tuner experience

[geoffff]

My 2004 Sportsmobile has the Ford gas v-10 engine, and I've been frustrated by Ford's speed limiter that cuts power at about 90 MPH. That might sound pretty fast, but it's been a problem for me quite a few times when trying to pass long vehicles on two-lane roads, especially in Mexico. There's nothing like having the engine cut out when there's another vehicle coming toward you at a combined 150 MPH when you're in their lane.

To work around this, I tried a couple of "performance tuner" devices, neither of which have worked out.

I tried the Superchips Tuner (1714: 1999-2004 gas engines), but while it supports the V-10 engine on the F-series trucks, it doesn't support the E-series vans.

I also tried the DiabloSport Predator Tuner (U7152: 1999-2004 Ford F350 6.8L), and while it allowed me to disable the engine computer's speed limiter, it caused my speedometer to read 10% too low. The DiabloSport Predator Tuners are supposed to support speedometer adjustment, but for some reason that feature isn't enabled on the U7152 for my van. It might just be a defect, but the DiabloSport people weren't much help when I called.

Has anyone found a better solution out there?

-- Geoff

[etbadger]

Hi Geoff,

One problem with a lot of the truck targeted tuners is going to be some differences in how the speedometer is driven (same issue for the diesels).

The trucks have a speed sensor on the rear axle, so the gear-ratio in the T-case, differential, etc has no bearing on the speed reading. They need only to adjust the computers concept of the tire size.

For the vans, since Ford does not make them with the 4wd option, and therefore there is no need to worry about T-case gear ratios, they simply read the speed of the output shaft of the transmission, and compute the vehicle speed based on the computers concept of the tire size AND the differential gear ratio. This is why the speedo is 3-4x off when in low-range in the vans.

For the trucks the computer doesn't care about the differential gear ratio (though the field is in there), but in the van it matters. Likely the tuners just ignore the gear-ratio as well, and it defaults to some common value (like 3.73).

-e

[calclimber]

I just had Troyer Performance do some custom tuning for my V10 http://www.troyerperformance.com/cgi-bi ... logno=9400 with dramatic improvements in performance. Not sure about the gas mileage yet Ill post later on that. They give you three custom tunes with the tuner. Now if I could just get my local Ford dealer to stop my transmission leak, going for the third time on Tuesday.

Craig
05 EB 50 V10 4X4 PH

[geoffff]

Thanks for the lead, Craig! Does your unit support the disabling of the speed limiter?

-- Geoff

[BroncoHauler]

Many people who are on TheDieselStop.com loves these guys (SCT), but I have no personal experience with them. They make tuners and chips for both gassers and oil-burners.

http://www.sctflash.com/product_SF.php


Herb

[calclimber]

SCT, That's the unit I have. As far as the rev limiter I don't know. Ill check it out this weekend. You can always call the company and ask. I recommend calling them direct they pick up your call right away.

Craig

[BroncoHauler]

I will say, there's been a lot of controversy over whether or not Ford will honor your warranty if you chip or retune your vehicle's computer. A lot seems to depend on the dealership you go to. Just something to think about.

Personally, I'll likely stay away from these oh-so-tempting items until after the warranty expires on my engine. I would be very hesistant to do anything to increase engine heat given the barely adequate air flow around the engine in vans.


Herb

[Scalf77]

Having had three “PDM’s” I think that is what they called them:” the processor controlling everything” blow up on me in the first 6000 miles , I will say that I have some experience in this area. Covering the cost of replacing the unit may be the least of your problems, when that part fails it’s as good as a paper weight, you can’t bypass anything and get around it. It will be a part that nobody stocks because of the low its failure rate. You can expect about four days of down time , not bad if your around town, but I didn’t purchase my Sportsmobile to drive around town. I’ll save my story of being towed out of Yellowstone for another day, but in the long run Ford did honor the warranty and put new parts in, they suspected that the problem was caused by the conversion, but never found it. My response to them at the time was "So what, don’t your engineers have a better way of protecting a critical part of the vehicle?" I do believe they were correct, the failure occurred because of a wiring error “not tightened correctly” in the Starcool relay panel. I guess my point is, that Ford covering repairs was not where I lost out, it was in time lost on my trip, hotel cost and rental cars.


Just my two cents


Greg
2004 E350 x3 EB V10

[calclimber]

This unit flashes the cpu with a new program and then I put the unit away. When i take it to the dealer I just reflash it back to stock. they claim no history of a mod. Believe me it brings out what the V10 should be doing from the factory.

[calclimber]

Scalf77

After re reading your post I see you say your main processor (the brain) failed. Now I am concerned, I have not heard this before. Definitely something to consider.