I bought a Superchip (normal one but I did have to solder a jumper in the computer - it was easy thanks to Mike T.'s instructions though) 'bout a year back and now I want to go with a 4.10LS in the rear. My concern is that the fuel curves and transmission shifts might be screwed up if I do this. What is the best solution?

Off topic- I have the 9.75 axle and need to know if the is LS upgradeable easily also? I think I found Auburn as a mfr. of the gear but need to make sure. Any input sure would help..

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1999 2WD F-150, Lariat, Deep Wedgewood Blue
Reg. Cab.,Stepside
5.4 (2nd One! due to piston slap after 18K), 3.55 L.S.
K&N Gen 2, SUPERCHIPPED


[This message has been edited by LaunchinLiteLariat (edited 04-21-2001).]

 

Hi LLL,

OK, going with the 4.10 gears in a 1999 or later model, becasue they no longer have a traditional reduction gear in the tailshaft of the transmission, you will need to have the Superchip updated with custom programming on both sides of the Flip Chip.

Recalibrating the speedometer error that will instantly result from changing to 4.10 gears will need to be done, to insure that upshift & downshift points as well as speedometer & odometer accuracy are all restored, and we can do that on many of those codes for that model year, so please just get in touch with us to make those arrangements, ok?

That 9.75 rear end is used in Lightnings & other FoMoCo vehicles in LS versions, so there are plenty of parts to go limited-slip.

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Mike Troyer
Performance Products, Inc.
National Distributor of Superchips
(540) 862-9515
Email: mtroyer@compuserve.com
Performance Products F150Online Superchip ordering system: F150Online Superchip Ordering System
First National F-150 Online Rally Event Organizer

 

Hey Mike!

Thanks for the advice, it sounds like I need to send the chip in for service BEFORE the gear goes in or I'll be driving a "Confused Computer" back from the shop and that's not too good.

Also, I was wondering what it would do to mileage, I figure a loss of ~14% due to the ratio but it may not be that much now 'cause Houston's going back to 55 m.p.h. on the freeway ! I guess my "Legal" rev's will still be about the same on the freeway
I'm figuring $8 to $12 a month more if the price doesn't go to $3/gal.for Super

I'll e-mail you with the details as soon as I get the info together.

LLL

 

Hi LLL,

By now, we've of course already spoken about all of this.

It's not that you *have* to have that custom program done *before* you have the 4.10 gearing installed, just that it's better that way. But that does not mean that you couldn't drive it either on the factory program or with your original Superchip, until you get the custom program back, the vehicle will still be driveable in most cases.

The ECU looks at mph via the VSS (vehicle speed sensor) for it's shift points, but if there is a conflict between the VSS & other data streams the ECU uses to confirm VSS, then it will default to using engine rpms to determine shift points, so the vehicle is normally still driveable, it's just not optimized & corrected like it needs to be so that the speedometer & odometer are correct and the ECU goes back to using MPH for determining it's shift points instead of defaulting over to using rpms.

Cheers!

------------------
Mike Troyer
Performance Products, Inc.
National Distributor of Superchips
(540) 862-9515
Email: mtroyer@compuserve.com
Performance Products F150Online Superchip ordering system: F150Online Superchip Ordering System
First National F-150 Online Rally Event Organizer