speedo corection

muddyhilux · Post by **muddyhilux** » Mon Sep 10, 2007 7:30 am

hi all,getin my track ready for cert and now have to overcome the speedo being out,does anyone kno of any kits u can buy or how to get around this??motors all standard,ive just incresed the wheels from 30 to35",cheers for any help,and sori if this has been asked b4,i couldnt find anything

xj · Post by xj » Mon Sep 10, 2007 8:48 am

Calculater bro. works for me.... im 18% out on circumference from factory, so i looked at the option of calculating the difference and remembering what speed im actually going, or changing gear ratios...... calculator cost $10.00....

niblik · Post by **niblik** » Mon Sep 10, 2007 8:56 am

could get something like this?

http://www.blackrobotics.com/yb_home.htm

rokhound · Post by **rokhound** » Mon Sep 10, 2007 10:07 am

Don't know that they are any good for cert, as odometer is not working, but for speedo, just get your self a push bike unit. Enter in the dimension of the tyre size and fit the gizmo thingee? to the inside of the rim (securely). Mount the computer part on the steering column with an led for a light, and you have a correct speedo for about $30

muddyhilux · Post by **muddyhilux** » Mon Sep 10, 2007 10:10 am

yeh ive been using that xj but that wont pass a cert will it??and have u tryed that yellow box niblik??

niblik · Post by **niblik** » Mon Sep 10, 2007 10:14 am

muddyhilux wrote: have u tryed that yellow box niblik??

nope bud... just thought it might help...

wjw · Post by **wjw** » Mon Sep 10, 2007 10:35 am

first thing to check is if you have a mechanical or electrical speedo.

muddyhilux · Post by **muddyhilux** » Mon Sep 10, 2007 12:09 pm

no worries nibs,it does look like it could be a valid answer,as foe ele tric or mechanical im not sure,does anyone kno??its a 1990 hilux 3y,actually it does have a cable of the gbox so i think i just answered my own question :oops:

wjw · Post by **wjw** » Mon Sep 10, 2007 3:52 pm

I have a little gismo that I bought for my prado, when I went from 245/75 R16's to 35's . Would probably work for you... can you un screw the speedo cable from the trans and take a couple of photos ? see if its the same...

mudlva · Post by **mudlva** » Mon Sep 10, 2007 4:01 pm

if your speedo cable is manuel contact marks adapters in ch/ch they have units that screw into the rear of the speedo cable fitting. off hand you will need 10% for 33's & 18/20% for 35's working on that your o/e tyres were 31's. if ch/ch cant help i know of a crowd in auck centrel that do speedo correction units for any vechile i cant remember there name at the moment, but if reqyuested will be able to find them.
cheers mudlva

xj · Post by xj » Mon Sep 10, 2007 8:02 pm

muddyhilux wrote:yeh ive been using that xj but that wont pass a cert will it??and have u tryed that yellow box niblik??

Mines certed without any speedo correction, be it with gizmos or altering gears. I figured that the whole certing issue pertaining to tyre size was to do with effective braking, not how your speedo reads.

muddyhilux · Post by **muddyhilux** » Mon Sep 10, 2007 8:15 pm

i will do wjw,get them up tomorow night,and mudlva i am actually in aucks so yeh if u wouldnt mind finding that number it would be much appreciated,just as a back up incase wjw's little gismo doesnt work,and as for certing yeh braking is a big bit of it xj but ive also been told that it wont pass unless my speedo reads right within bout 5% i think it was,cheers for all the help so far tho guys

mudlva · Post by **mudlva** » Mon Sep 10, 2007 9:08 pm

Hi there muddyhilux the crowd is
Robinson Instruments Services
Head Office
19 Sale Street, Freemans Bay.
Auckland 1030
P.O. Box 90-104
Auckland Mail Centre
New Zealand

Phone: +64 9 377-1565
Fax: +64 9 358-0573
Email: robinson@woosh.co.nz

Talk to these guys they have helped me out with speedo cables etc and got all sorts of stuff to get your speedo spot on
cheers mudlva

wjw · Post by **wjw** » Mon Sep 10, 2007 9:36 pm

I have one of those speedo adapters, had to take it off when I changed the diff ratios... so if it will fit, you can have mine for less than the $250 is cost me ;-)

TJ · Post by TJ » Tue Sep 11, 2007 12:22 am

xj wrote:Calculater bro. works for me.... im 18% out on circumference from factory, so i looked at the option of calculating the difference and remembering what speed im actually going, or changing gear ratios...... calculator cost $10.00....

On a Wrangler changing the speedo gear is ten minute job. You can buy the gear from the dealer (I bought mine for $25). Its probably the simplest thing to do. Just read this for a quick refernece.

http://www.ilovejeeps.com/forums/showthread.php?t=11657

and this is what the gear looks like. Let me know if you need more info.

http://www.quadratec.com/products/55200_33.htm

muddyhilux · Post by **muddyhilux** » Tue Sep 11, 2007 8:05 pm

well its not the best pic wjw but here its is

also those gears look simple as TJ,do u kno if toyota has this same system?

wjw · Post by **wjw** » Tue Sep 11, 2007 8:32 pm

Looks the same as mine... When I next go into town I'll grab the adapter thing... PM me your address and I'll post it...

Cheers,

Bill

TJ · Post by TJ » Tue Sep 11, 2007 10:02 pm

muddyhilux wrote:also those gears look simple as TJ,do u kno if toyota has this same system?

I don't know much about Toyotas. I doubt it though, Wranglers are designed to simple to work on (nothing much has changed in a long long time). Those gears that I had put a link for a okay for NP231 transfer case (which comes in a lot of trucks in US including Jeeps, Dodge Durangos and Chevys).

muddyhilux · Post by **muddyhilux** » Fri Nov 09, 2007 7:40 pm

ok guys well after a bit of testing it turns out bills adaptor aint right,now ive been in contact with marks adaptors and they can get me what i need but i cant work out the %,tyre specs and workings say i need 21%,ive gone from 235/75/15 to 35"bfgs,but marks recon this may not be correct and say i should gps test,but i aint got access to these facilitys,but today i drove my standard car 10kms and then drove my truck that same distance and speedo says 8.85 so that works out to bein 11.5km out for every 100km,so that would be 11.5% which isnt quite half,which one do i go by??or am i doing it completly wrong??any help appreciated,thanks

wjw · Post by **wjw** » Fri Nov 09, 2007 7:56 pm

I would suggest you ask on here and see if you can borrow a gps for a few hours. there must be somewhere like parrots down here up there... ie someone who can do it for you... once I get that box back I'm going to take it in and get it adjusted so it works for my truck again.. had enough speeding tickets now...

meatc · Post by **meatc** » Fri Nov 09, 2007 8:06 pm

[url]4wdbits.co.nz[/url] has a tyre calculator in the tech stuff.

235/75/15 is about 29inch 35 should be 35

Put those in the calculator on there and comes up with difference of 20.68%

If you want to be safe google tyre calculator and there are heaps of differnt ones. There are prob some around that will let you put diff ratio changes in as well.

Hope ths helps

TJ · Post by TJ » Fri Nov 09, 2007 8:18 pm

You have gone from 28.88 inch tyre to 35 inch ones.

Where abts are you in Auckland?

meatc · Post by **meatc** » Fri Nov 09, 2007 8:26 pm

Try this site. All the calculators youll need and more. might scare you if you havent altered your crawl ratio (new diffs or trans case gears)

http://www.4lo.com/4LoCalc.htm

xj · Post by xj » Fri Nov 09, 2007 9:29 pm

Still gotta sort mine out. Picking i need the "36" version. Ah, ill get around to it one day.

skid · Post by **skid** » Fri Nov 09, 2007 9:59 pm

buy a radar detector that has a GPS function that gives you a read out of the speed you are doing.

not sure if its legal or not, but they are a shit load more accurate than a speedo

mudlva · Post by **mudlva** » Fri Nov 09, 2007 10:44 pm

go in and see the guys at robinsons they have a rolling road and will get it spot on. if you have a full time four wheel drive you will have to remove the front drive shaft. these guys have got all sorts of goodies so it is worth the visit

muddyhilux · Post by **muddyhilux** » Sat Nov 10, 2007 5:14 am

yeh had wondered if anyone might have one wjw,and thanks meatc,did that the other night and got that,n yep tj thats what i got and thats y im sure ive worked it out correctly,im in weymouth down south and yeh i have thort of that idea skid but yeh not quite legal i believe,was even thinkin buy one,test speedo and then return it but then if they wont take it back im buggered and mudlva,i would like to go to this robinsons place but bein that my truck it now quite moded,no wof and rego on hold and does look rather aggressive i dont wana risk my chances of getin there and back with out getin pink stickered,i like to do things the legal way,even tho sometimes harder ,but yeh thanks

MNC · Post by **MNC** » Sat Nov 10, 2007 5:26 am

For those who have an electronic speedo I found this interesting...

http://www.project-tinfoil.co.nz/step5.htm

UBZ · Post by **UBZ** » Sat Nov 10, 2007 8:57 am

http://www.jaycar.co.nz/productView.asp?ID=KC5435&CATID=&keywords=speedo&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=

Jaycar sell this kit for electronic speedo correction

TJ · Post by TJ » Sat Nov 10, 2007 10:30 am

xj wrote:Still gotta sort mine out. Picking i need the "36" version. Ah, ill get around to it one day.

Get it from the dealer. Do you want me to check around? Its very cheap.