diff gears affecting speedo?

[hispeedvp]

am purchasing some diff gears for the vp. 3.7's, how much will these affect the speedo and how can i correct it?

[pumba]

ive got a VP SS 5.0Ltr (with IRS ) and i have 3.9:1 diff gears. my speedo is out by about 20km/h with 18" mags. so if my speedo is sittin on 100km, then im only doin 80km. holden has told me that if i give them my overall rolling diamiter of the tyres/mags, what diff gears i have, what the final drive is, and something else (cant remember lol) then they can change it thru tech2. or they can just get another car with accurate speedo and go for a hi-way drive next to it and change it that way lol

[AirStrike]

ive got a VP SS 5.0Ltr (with IRS ) and i have 3.9:1 diff gears. my speedo is out by about 20km/h with 18" mags. so if my speedo is sittin on 100km, then im only doin 80km. holden has told me that if i give them my overall rolling diamiter of the tyres/mags, what diff gears i have, what the final drive is, and something else (cant remember lol) then they can change it thru tech2. or they can just get another car with accurate speedo and go for a hi-way drive next to it and change it that way lol

Tech 2 can't be used to change it, that's for the VT onwards. They can't change it even using the Tech 1 as the ECU/BCM doesn't control the speedo readout at all. I'll post up what you need to use later, just have to find the name of it.

[1991_Vn2nV]

You need a kit from Jaycar Electronics. Speedo Corrector kit. Its a do it yourself kit that you make yourself using resistors etc. to change the signal to the speedo and in effect change what speed the speedo thinks you are doing.

[AirStrike]

You need a kit from Jaycar Electronics. Speedo Corrector kit. Its a do it yourself kit that you make yourself using resistors etc. to change the signal to the speedo and in effect change what speed the speedo thinks you are doing.

Thats the one!! Couldn't for the life of me remember what they were called.

[1991_Vn2nV]

They used to be on the Jaycar website but arent there anymore and I thought they stopped making them... But as it turns out they still do

Apparently alot of truck drivers use them to overrule their speed limiters too.

RRP is around $47 from memory.

[vpssguy]

yeah ive got 4:11s in my vp 5 litre its out 40 klms so if im doin 140 im only doin 100

[hispeedvp]

cool will try jaycar, thanks

[Boonz]

dont go there its cheaper to send your cluster to a VDO gauge repairer. it takes 5 minutes to recalibrate the speed sensor in the cluster and only costs about $80

[cracker]

that would be the way to go as peanuts suggested

[1991_Vn2nV]

dont go there its cheaper to send your cluster to a VDO gauge repairer. it takes 5 minutes to recalibrate the speed sensor in the cluster and only costs about $80

How is that cheaper than a $45 speedo correction unit tho?

[10000_fists]

My vp has 3.7 diff gears and on 120-123 its 100ks

[STEALTHY™]

Same as above


btw sick wheels!


VN2NV, is there a Jaycar here? cant say i've ever heard of them.
Although peanuts idea sounds more like what i'm after.

[1991_Vn2nV]

Same as above


btw sick wheels!


VN2NV, is there a Jaycar here? cant say i've ever heard of them.
Although peanuts idea sounds more like what i'm after.

Yeah there is, theres one in town... Not sure if there are more? Take a look in the phone book or contact Miss E...

[glynmo]

dont go there its cheaper to send your cluster to a VDO gauge repairer. it takes 5 minutes to recalibrate the speed sensor in the cluster and only costs about $80

Do you have any details for one of these places?

I checked google, but couldnt find anything.

Thanks

[STEALTHY™]

If your talking about SA, theres a VDO on Port Rd, just before it veers off to old Prot Rd.

[hispeedvp]

jaycar list nother, there us also a company call electus, who are also jaycar but they list nothing, if i find a VDO repairer in Perth will let ppl know, i've got three speedos here could get them all calibrated for 3.7's and sell them here or on ebay maybe?

[woteva]

jaycar list nother, there us also a company call electus, who are also jaycar but they list nothing,

Jaycar Speedo Corrector MkII Kit $49.95 CAT. NO. KC5435
This kit alters the speedometer signal up or down from 0% to 99% of the original signal.
LINKY HERE

[jNINE]

I bought one of the jaycar kits yesterday, and one of their plastic boxes to fit it into. I don't think you can recalibrate the dash display, well not on a VR anyway (I looked into that one). I still have to get the shift points remapped via kalmaker after fitting the speedo corrector.

[1991_Vn2nV]

jaycar list nother, there us also a company call electus, who are also jaycar but they list nothing, if i find a VDO repairer in Perth will let ppl know, i've got three speedos here could get them all calibrated for 3.7's and sell them here or on ebay maybe?

As I originally posted:

They used to be on the Jaycar website but arent there anymore and I thought they stopped making them... But as it turns out they still do

Apparently alot of truck drivers use them to overrule their speed limiters too.

RRP is around $47 from memory.

No longer listed, but they still sell them.

[flyen]

i just got my diff rebuilt with 3.45 gears
speedo is about 10k's out now

[Lost_Pete]

This spreadsheet may help, you will need to unzip it.

I think it's correct as I spent about 2 minutes to create it.