XJ Mods VSB 14

[werd]

Originally Posted by alexbrown64

The Yellow Box speedo recalibrator arrived the other day. I read the instructions on how to calibrate it after a bottle of wine and it made no sense at all. The next day i re-read it and it all came together. You can get one of these from http://yellr.com/ . I got the plug n play version so i dont have to worry about splicing wires. Their customer service is great and the product looks high quality. The reason i need one of these is because according to Go-Jeep, with my 4.88 diffs and 29 inch tyres, i would need a 47 or 48 tooth speedo gear... which they dont make. So this calibrator solves the problem and i can change tyre sizes any time and simply recalibrate.
I will fit the yellow box up next week and do a write up, but i thought i would write up on how the yellow box v5 is calibrated. Firstly you need to work out how much your current set up throws the speedo out. Do this by [new diff ratio/old ratio]x[old tyre diameter/new diameter]. My calculator said 1.3460 which is 134.60% which is 34.60% fast.
You then hold down the two buttons on the yellow box (pic below), for 5 seconds to go into adjustment mode. There is a + and - button. For each second you hold down the + button, you adjust forward 1%. So i needed to hold down the + button for 34 seconds. You tap the + button to get thet smaller 0.6 increments. So i tap the + button six times. Then you wait a few seconds for it to go into memory and then turn it off to store the data.
After that, use a gps, road markers, etc.. to check it and make small corrections as necessary.

Sweet!
I have a Jaycar unit I use on my Sportage that wires into the back of the speedo. On the Jeep I tried putting it between the speed sensor unit and the ECU. It picked up the signal but couldn't calibrate it. Stayed on 40km/h. Ended up going with a new speedo gear cog.

[junglejuice]

Originally Posted by alexbrown64

with my 4.88 diffs and 29 inch tyres, i would need a 47 or 48 tooth speedo gear...

Wow!! That must be fun to drive on the highway, be awesome in low range offroad!!!

[alexbrown64]

The gearing is not the best as it was designed to go with my 35" tyres. According to Go Jeep, this gave me "RPM's at 65 MPH/105 KPH w/ 4.88:1 axle gears running 35's: 2,284 RPM". Now i have something around "RPM's at 65 MPH/105 KPH w/ 4.88:1 axle gears running 28's: 2,855 RPM", so i could do wheelies of the lights. Standard is "RPM's at 65 MPH/105 KPH w/ 3.55:1 axle gears running 28's: 2,076 RPM". I think the sweet spot with XJ's is around 2400rpm with large tyres and extra weight http://go.jeep-xj.info/HowtoSpeedoGears.htm . This setup is only to pass inspection... down the track i am looking at some Deegan or KM2 33" tyres which should give me RPM's at 65 MPH/105 KPH w/ 4.88:1 axle gears running 33's: 2,422 RPM.

I was thinking the Jaycar unit as well Werd, but saw this one and i thought it was pretty good and their customer service is great. I emailed them this Saturday afternoon about cutting the wiring loom down and got a reply within an hour!!
Anyway, i checked out the XJ for a location for wiring and the yellow box. The gear plugs under the car are right next to the handbrake. The handbrake sits in a large plastic dish that is perfect to drill and poke some wires through and then seal up with some silastic. I will route the cable up from underneath and then into the centre console. The centre console will be a great place to make adjustments from, and it will be hidden under the lift up arm rest door.

[junglejuice]

Originally Posted by alexbrown64

The gearing is not the best as it was designed to go with my 35" tyres. According to Go Jeep, this gave me "RPM's at 65 MPH/105 KPH w/ 4.88:1 axle gears running 35's: 2,284 RPM". Now i have something around "RPM's at 65 MPH/105 KPH w/ 4.88:1 axle gears running 28's: 2,855 RPM", so i could do wheelies of the lights. Standard is "RPM's at 65 MPH/105 KPH w/ 3.55:1 axle gears running 28's: 2,076 RPM". I think the sweet spot with XJ's is around 2400rpm with large tyres and extra weight http://go.jeep-xj.info/HowtoSpeedoGears.htm . This setup is only to pass inspection... down the track i am looking at some Deegan or KM2 33" tyres which should give me RPM's at 65 MPH/105 KPH w/ 4.88:1 axle gears running 33's: 2,422 RPM.

In my experience the sweet spot is close to a stock limited so 225/70/15 on the 3.55's or 225/75/15's on 3.73's, slightly higher rpm's at 100 then a sport, better performance and better economy...

[alexbrown64]

Had a go at installing the yellow box speedo re-calibrator. It was a bit of hit and miss. Made a bracket and installed the box inside the centre console and that bit worked out well. I have made a hole down through the console directly above the handbrake and drilled through the plastic grommet under the handbrake to run the cable. The transmission plugs are only 20-30cm away. The miss part was that the supplied plug n play plugs did not fit. I have emailed them and either they can send me a new harness, or i will splice into the existing one.
According to the net, the speedo wires are as follows..
Wire 1 =
power
(constant +12 volt, or +5 volt) Orange wire.....
Wire 2 =
ground
(main vehicle earth) Black/light blue wire....
Wire 3 =
speed signal wire
(measures 0 volts then
12 volts (or 5 volts) as the wheel is rotated) square wave. Orange/white wire.....
I can run a multi meter on them tomorrow. Next step is to put console back in Jeep and tidy it all up...

[alexbrown64]

I am still waiting on a reply from Yellr.com in regards to what i am going to do with wiring in my Yellow Box.
So, i finished off painting the quick disconnect mud flaps and they are ready for installation. The 22" light bar arrived today. I am on a budget, to i went for one described as "22INCH 200W PHILIPS LED LIGHT BAR SPOT FLOOD COMBO" from Fleabay. Only $69 and i know you only get what you pay for, but i will give this one a go and report back. I needed to fab up a mounting bar, so i searched the shed and found some 25x50 rhs which worked out perfect. I mounted it up as per VSB14 regulations here.. http://www.transport.wa.gov.au/media...VS_IB_132A.pdf
There is an exemption to have 1 light, but it cannot be mounted on the roof or above the bonnet line. The perfect spot in the bullbar and this factory bar has some mounting points for spotties which is used to attach my mounting bar. I was quoted $300 a while back to wire up some spotties at an electricians and that was with my supplied wiring harness. I did not go ahead, but i remembered the costs, so i bought a DIY "back to high beam" full harness from Stedi which is still on the way. Pic below of new light bar. Will mount quick release mud flaps tomorrow and post pic.
Cheers,

[alexbrown64]

Fitted up the quick release mud flaps this morning. Only took 10 minutes using 10g x 25mm galv tech screws (4 in each bracket). Solid as a rock and another point towards getting the XJ through inspection.



List of parts:
2 pieces 500 x 20x20mm rhs
2 x plastic end caps for 20mm rhs
2 pieces 100 x 25x25mm rhs
2 pieces 100 x 50mm flat bar
2 pieces 500 x 25x25mm flat bar
10 x 6mm nuts and bolts
8 x 10g x 25mm tech screws
2 x 450 x 300 strips of rubber (I used 10mm thick used conveyor belt)
Spray paint

Tools:
Welding machine
Grinder
Tape
Drill with 6mm or 6.5mm bit
Bit for tech screw
File

Cost: If you have some bits and pieces laying around, you can fab these up in a few hours for less than $30 total. A steel yard will just about give you the off cuts, and there are places around that sell conveyor rubber for cheap.. look on Gumtree.

Savings: Depending on where you were thinking of buying them, you can save between $100 and $200 dollars. These ones for sale at Murchison cost $275 http://www.murchisonproducts.com.au/...ease-mud-flaps

Cheers,