4.375 Diff Ratio In Gtr

[pnblight]

Hi Guys,

Just completed my diff ratio swoop in the gtr from 4.11 to 4.375(gts4) and i was wounder if anyone knew how to alter the speedometer to read correctly. As i believe it should be out now yes? Any help would be much appreciated.

pete

ps did search with no luck

[SteveL]

  pnblight said:

Hi Guys,

            Just completed my diff ratio swoop in the gtr from 4.11 to 4.375(gts4) and i was wounder if anyone knew how to alter the speedometer to read correctly. As i believe it should be out now yes? Any help would be much appreciated.

<{POST_SNAPBACK}>

It will be out, but changing the speedo drive pinion at the gearbox will fix that. Someone might have a secondhand one from a GTS4 gearbox, but the part number for a new one from Nissan is:

32703-05U21

[pnblight]

steve you the man thanks

[blind_elk]

Look up the businesses under "speedometers" in the Yellow Pages. Apparently they can re-calibrate the speedo with a "black-box" converter / adjuster.

Steve, what's the P/N for the Stagea's drive pinion?

[Bl4cK32]

how much difference is there going from 4.11 to 4.3?

[funkymonkey]

no need to recalibrate if you change the speedo pinion.

here is the R32 GTR one:

here is the R32 GTS4 one:

the difference is 20 notches on the GTR one and 21 on the GTS4 one, it should swap straight in. The difference in speed you'll see on the speedo is roughly 0.3%.

The part number of the GTR pinion is 32703-05U20. THe GTS4 one is 32703-05U21. Just ring up nissan and grab it from them, it should be about $50.

[SteveL]

  blind_elk said:

Steve, what's the P/N for the Stagea's drive pinion?

<{POST_SNAPBACK}>

Greg - what's the Stagea model designation ??

[pnblight]

that sound about right

4.11/20=0.2055 x 21 =4.3155 (close enough 4.375)

thanks guys

[blind_elk]

  SteveL said:

Greg - what's the Stagea model designation ??

<{POST_SNAPBACK}>

I think its "C34"

[blind_elk]

  funkymonkey said:

...The difference in speed you'll see on the speedo is roughly 0.3%.

<{POST_SNAPBACK}>

The difference is more like 5% (21 is 1 more than 20, ie 20 + 1/20 * 20, and 1/20 = 5%). Fortunately, the speedo will now read higher than reality, so far less likely to get photographed.

The error in mine, having gone from a GTS4 to a Stagea (4.083) diff, is roughly 7%. But mine reads under the real speed - caution, Will Robinson!

[funkymonkey]

oh whoops... meant 3% not 0.3%

[sky30]

  funkymonkey said:

no need to recalibrate if you change the speedo pinion.

here is the R32 GTR one:

the difference is 20 notches on the GTR one and 21 on the GTS4 one, it should swap straight in. The difference in speed you'll see on the speedo is roughly 0.3%.

The part number of the GTR pinion is 32703-05U20. THe GTS4 one is 32703-05U21. Just ring up nissan and grab it from them, it should be about $50.

<{POST_SNAPBACK}>

Are you sure the one on picture 2 is a GTR one, cause when i ordered a GTR pinion drive i got a RED gear, and the teeth are angled back the opposite way to my GTS4 gear. I tried to fit the RED GTR gear it in my GTS4 box but it wouldnt go in.

Are there 2 different GTR gears?

[Bl4cK32]

I had a r32 gtr speedo and its the same as the one funky showed. The red one is the same as the one im using now Andrew, and its out of a r33 box.

[SteveL]

  sky30 said:

Are you sure the one on picture 2 is a GTR one, cause when i ordered a GTR pinion drive i got a RED gear, and the teeth are angled back the opposite way to my GTS4 gear. I tried to fit the RED GTR gear it in my GTS4 box but it wouldnt go in.

Are there 2 different GTR gears?

<{POST_SNAPBACK}>

Hmmm, interesting.....according to FAST the gear in the ATESSA housing that drives the pinion shown in those photo's has the same part number for both GTR and GTS4 - it is identical in each case, so the pinion gear teeth form should also be the same.

[eXc]

just get it on a dyno...that's what i did, mine is out by 11% or something, reads 122kms when I am doing 110

[funkymonkey]

Speedo Pionion assembly for the Stagea is:

32702-5P519 for the Aug 1998 and newer (auto and manual)

32743-0V120 for Sept 1996 to Aug 1997 (auto only)

32743-0V120 for Aug 1997 to Aug 1998 (auto only)... slightly different transfer assembly, but pinion is the same.

[T04GTR]

gts4 is 4.336:1 :lol:

[pnblight]

  T04GTR said:

gts4 is 4.336:1  :lol:

<{POST_SNAPBACK}>

gts 4 has 8 to 35

ratio 4.375

gtr has 9 to 37

ratio 4.111

[T04GTR]

  pnblight said:

gts 4 has 8 to 35

ratio 4.375

gtr has 9 to 37

ratio 4.111

<{POST_SNAPBACK}>

ahh. im thinking of gtst, woops

[sky30]

  SteveL said:

Hmmm, interesting.....according to FAST the gear in the ATESSA housing that drives the pinion shown in those photo's has the same part number for both GTR and GTS4 - it is identical in each case, so the pinion gear teeth form should also be the same.

<{POST_SNAPBACK}>

Dont know why the one i have has the teeth angled the opposite way, i have a VLturbo(MX7) drive gear hear also the teeth are angled the same way as the RED GTR gear i have....

The RED spedo gear i have works fine in my R33 turbo box, but wont go in the GTS4 box.

Will try and get some pics up.