Rb25 Gearbox Speedo Conversion For R32

[PSI086]

We did this a few years back with my brothers car and its still working fine to this day. The VL gear is a smaller OD as you can see in the first pics and wouldn't mesh with the gear in the box, hence no speedo signal

[fullspooldrifta]

i used the same system for a cefiro with a 25 box worked perfectly, i used the navara speedo drive (32702-02G17) nissan part no. burnt the cog off, used the red gear on the speedo drive out of the r33 box. rounded out the middle of the cog, heated up the navara drive and tapped it on, super glued both ends. cut the slot for the locator and all good.

cheers heaps

[Char]

ive got a gtr one in mine atm but it reads like 10-20-30kph off (increases with speed)

is the navara/vl one accurate?

(it doesnt bother me too much having wrong speed as i can gauge off the revs-except in school zones.. dam 40kph have no idea what speed im doing)

Edited August 19, 2010 by Char

[SimonR32]

mine is way out using just the navara drive... i will get around to fitting a r33 red gear one day when i can be bothered

[bubba]

I'll have a search for my post with the cog tooth count vs final drive ratios.. the 17T standard Navara cog is a pretty close match for my 3.9:1 diff gears (reads 7km/h high), you need the correct toothed cog to suit your diff gears.

[SimonR32]

  bubba said:

I'll have a search for my post with the cog tooth count vs final drive ratios.. the 17T standard Navara cog is a pretty close match for my 3.9:1 diff gears (reads 7km/h high), you need the correct toothed cog to suit your diff gears.

7km/hr at what speed?!? The amount that the speedo would be out would vary with speed...

Mine has a 4.3 ratio diff and is out by about 7km/h at 60km/h but 10km/h at 100km/h etc etc

[bubba]

  SimonR32 said:

7km/hr at what speed?!? The amount that the speedo would be out would vary with speed...

Mine has a 4.3 ratio diff and is out by about 7km/h at 60km/h but 10km/h at 100km/h etc etc

@ 100km/h I'm actually doing 93km/h

[SimonR32]

  SimonR32 said:

7km/hr at what speed?!? The amount that the speedo would be out would vary with speed...

Mine has a 4.3 ratio diff and is out by about 7km/h at 60km/h but 10km/h at 100km/h etc etc

i was actually wrong, at 72 speedo im doing 60 gps and 127 speedo 100 gps

in other words its miles out

[bubba]

  SimonR32 said:

i was actually wrong, at 72 speedo im doing 60 gps and 127 speedo 100 gps

in other words its miles out

That makes a lot more sense

[Willis]

Bump, any chance we could get the images fixed on this thread! I need to do this conversion!

Thanks!

[666DAN]

For anyone who prefers soldering to DIY'ing with tools

http://www.jaycar.com.au/productView.asp?ID=KC5435

[Samgrainger32]

whats the go with the images on this thread need to get them working asap!!

[itssam]

need a new thread like this with photos

[amnash]

just had a sensor shaft snap after this mod. the pics arent working can someone explain the 180degrees out for the locator pin for me? i didnt do any of that and maybe thats why it snaped. i just pressed the cog on and installed.

[DriftSquad]

Is there anyway to fix the pictures in this DIY ???

[Garret_Volden]

Any chance at all that the original pictures can be re-added 

[255k]

Did the conversion today and I took some pics as the original images are down.

Required parts.

What the drive looks like - note this one *came out* of the gearbox (didn't know what was in there). I didn't get any pics but I used a combo of a (n eventually plastic coated) cutting wheel, carbide cutter and a carbide burr on the dremel. You can see remnants of the removed black gear in the bottom right of the image. Recommend you melt it off instead, it'll be a lot quicker and less worried about damaging the spline on the shaft but messier.

What I didn't get was a picture of the flat I cut into the splined shaft. Cut 12mm down from the edge to match the new gear, or cut the flat from the gear. Either way works.

Note the gear shaft offset from the body. Also note the notch in the centre bottom, above thumb nail.

Note the difference in gear size. The shaft housing needs to be rotated 180 degrees to make room for the bigger gear. The body will spin in the gearbox but you'll need to cut a new slot for the retainer.

Original retainer location in relation to notch.

*NEW* retainer location in relation to notch which needs to be made. It's mirrored around the notch. Approx 3.5mm deep x 20mm tall and 4mm away from the edge (from memory).

Cut it with three hacksaw cuts. Could use a dremel or a square file instead.

I didn't neaten it up at all as I had already cut a tiny bit too far.

New gear on. I applied a bit of araldite to the flat area just to be safe. Don't use superglue as I think it may melt the gear. Notice I started cutting the flat out of the gear, before realising I could cut the shaft instead (and would provide better location on the shaft, not that I imagine there's much force on it anyway).

Note, the gear doesn't bottom out on the housing like the black gear. Top of gear is flush with the shaft (as shown in an earlier photo).

Going into the gearbox - if the gears are meshed, it should slide up to here with minimal effort. Note the location of the notch in the speedo drive body (should be pointing down).

All done!