speed limiter

[sneh]

after changing the diff ratio in a friends EF, we have since found that the speed limiter cuts in at 140... is there any way of removing the limiter via software, or will we have to do it the hard way and get a pulse multiplier/divider and bend the VSS signals?

[arm79]

We assume you have also changed the speedo gear in the transmission to suit the new ratio?

[sneh]

hmmm... if my memory serves me correct all the ones ive replaced before in taxis had the same red(ish) gear, all the way from ED when i started to the EL's... all the AUs were still under factory warranty when i left so i never had to do anything on them.
Although... correct me if im wrong, but the gearbox output speed should still be the same as with the standard diff, just turning the wheels more times per GB revolution should it not??

[arm79]

If they had the same colour it means they were all for the same diff, which im guessing is for a 3.08.

If you change the diff, the speed at which the gearbox output is the same, but the speed at which the wheels turn is different. The different speedo gears compensate for this.

What diff did you take out, and what did you replace it with.

http://www.fordmods.com/phpBB2/documents.php?doc=30

See that link for further info...

[jonbays]

go and get a black 23 tooth speedo drive gear from ford for $8 and put that in. It will get the speedo closer to reality and up the speed limiter.

[Disco Frank]

[richie]

I have ED 5.0L Fairmont - i think diff is open centre 3.27. Am doing engine mods for more KW.
Can I change diff to LSD from NC Fairlane and change ratio to 3.45 for more acceleration?
Apart from speedo sender gear what else needs change ?
Does the EECIV need changing/edit?
Any conflict with auto trans ratios?

Richie

[Nanger]

I thought AUs were the first ones with a speed limiter. Feel free to flame me if I'm wrong, but I aint never heard of anything earlier than AU being limited.........

[Casper]

There is only one way to remove the limiter and keep the speedo correct.

Brief note: The limiter is controlled by the ECU and is not an actual speed limiter as much as a tailshaft rpm to gear ratio limiter. That is why when changing the diff the speed limititer drops. As far as the ECU knows the car still has the original diff gears. Therefore X rpm in X gear = 180kph, the safe operating point of the tailshaft. Unfortunatly, with a different diff, this calculation produces a lower speed as it takes more rpm's to achieve the same speed.
The only way to change this is to either increase or remove this limiter and that, at this point, is only possible through a chiptorque chip that plugs into the ECU and overrides certian parts of it.

Also, be warned, that tailshaft limit is there for a reason and WILL start to vibrate quite badly.

The XR's had a different tailshaft and therefor had a higher limit.

[Disco Frank]

[Daniel]

EL GT and NL FBT arent Limited as such, could swap ECU's..
The ECU is hard to get ahold of, but not impossible!

[Casper]

Actually, I have to change my comment on the chiptorque chip being the only way. There is also a way to do it with the unichip too called speed clipping. Although the unichip cant change rev limiters etc it can remove the limiter. So there you go, another piece of info for you all.

[NOCLAF]

i think speed limiter came in on EB seris II... when i looked at a EB XR8 about 6 months ago the guy said it was the last model before speed limiters... my cousins EA 5 speed mont would sit on 200 so that wasnt limited

[AXR88U]

If its auto and you change the speedo gear alone you will bugger up the shift patterns

[voids]

are speed limiters on a standard falcon different then a fairmont?? coz I can get 191Km/h out of mine before cutout.

[Bozz]

[Rapier]

well if ure gonna go that fast anyway make sure u but tail shaft loops in, afaik the reason for the limiter was becaus high speeds caus the drive shaft to snap.
The XR's FBT and GT got a better driveshaft and hence why the do not have a limiter in place.
The cheapest option is probably to get an XR ECU, but as i suggested get tail shaft loops, one snapping at 200 km/h probably wont be fun ay

[Bozz]

Good advice regarding the tailshaft, Rapier

[daro]

[Bozz]

My old man's ED with the EEC4 certainly cuts out at 180km/h.

On the dyno of course. Doing it elsewhere would be dangerous. Or something.