4.36 final drive.....speedo off!

[fuk240sx]

Hey, so I just put in a 4.36 lsd diff into my s13 and I knew that my speedo would be off but how can i rectify the situation, I mean which speedo pinion would i need to use??

[UNISA JECS]

Im not sure there is a speedo pinion gear swap that you can do as I think the highest speedo pinion you can get it a 21 tooth. You would probably need a 23 tooth pinion.

[fuk240sx]

any idea where I might be able to get a 23 tooth? or is there any way I can calculate how far off my speedo is so I know how fast I'm going on the highway atleast?

[nsn240]

I never knew correcting it was an option... It's not all that far off, been driving with it for 3 years now

[fuk240sx]

I dunno it seems like its really off especially when I'm on the highway....seems like I'm always doing 75mph+

[S14DB]

Doesn't dakota digital sell a correction device?

[fuk240sx]

That might be another reason I'm on 16" right now with like 225/50/16

[UNISA JECS]

All things being equal and yoru rolling diameter is close to what the factory intended at 75mph with a 4.08 and a 21tooth pinion, you'll be reading ~5mph faster than what you should and it just gets worse as teh speed increased at 150mph you'll be about 10mph off.

[S14DB]

Universal Speedometer Signal Interface

[fuk240sx]

The stock pinion is 21 teeth right?

[UNISA JECS]

Originally Posted by fuk240sx

The stock pinion is 21 teeth right?

Yes, there are some that came with 20 tooth but the majority I have seen are 21tooth.

[fuk240sx]

Thanks alot man I appreciate your help!

[bec1488]

- - - - - - - - - - - -

[JRas]

Originally Posted by UNISA JECS

All things being equal and yoru rolling diameter is close to what the factory intended at 75mph with a 4.08 and a 21tooth pinion, you'll be reading ~5mph faster than what you should and it just gets worse as teh speed increased at 150mph you'll be about 10mph off.

I'm guessing 4.63 would be even worse?

[fuk240sx]

Originally Posted by bec1488

Sorry bout the off-topic, but did you buy the Nismo 4.36 R&P set or find another option? Happy with it? I'm considering the same change for my S13.

I was talking about the rear lsd diff.....not the rack&pinion

with a rear end of 4.63 you would be off by about 9mph at the speedo showing 75mph....so with the speedo at 75 you would be doing 66mph and with the speedo at 100mph youd be at 88mph.....so yeah it would be worse

[S14DB]

Originally Posted by fuk240sx

I was talking about the rear lsd diff.....not the rack&pinion

Ring & Pinion? The Ring is the gear around your LSD hub and the Pinion is the input gear in the case.

[racepar1]

Originally Posted by bec1488

Sorry bout the off-topic, but did you buy the Nismo 4.36 R&P set or find another option? Happy with it? I'm considering the same change for my S13.

I LOVE my 4.36. It really livens up the stock ka and it doesn't rev too high on the freeway. I'm at about 3500 rpm at about 75mph. I'm considering the 4.6 though as the 4.36 made such a difference.

[superJoy]

CA18DET or RB20DET sensors might work

They both had 4.36 final from Nissan

I just put a 4.36 in my car, and the speedo is definitely off. But it reads fast so you're not going to get pulled over for speeding, at least. I've had it in for like a week, I think it's around 4 mph off or so at normal driving speed. Not really a big deal

I actually have a CA18, so as soon as I'm not feeling lazy I'm going to swap the sensor out (put the KA one in when I did the swap, since I knew final drive was different) and see what happens.

Honestly on the CA18 (torqueless wonder of the world) I was disappointed with the 4.36. I'm sure it hauls ass on a KA, but CA18 almost needs 4.6 just around town. Hahaha. It's quicker but nothing too dramatic

[fuk240sx]

Originally Posted by S14DB

Ring & Pinion? The Ring is the gear around your LSD hub and the Pinion is the input gear in the case.

^^^^^^^^
Lol........yea but this is awesome on an NA ka, it accelerates alot faster and feels more responsive in general. I think the 4.63 might be too much if you plan on daily driving the car though..my .02

[Ktown_drifter]

not sure wht my gearing would be in mine.. Ive just insalle it.. havent had time to try it out yet.. R32 Diff with nismo 1.5 way.. any idea what the gearig would be compared to my stock 1990 s13 diff?

[superJoy]

I just went out to the garage and dug out my CA18DET speedo sensor

Unless I miscounted.... it's 23 teeth.

So that's the ticket.

CA18 trans is different ratio than KA/SR/whatever, but that 23 tooth fella should get you closer. Don't know where you can get one though... you're on your own. Heh.

[UNISA JECS]

The CA18DE(T) AT uses a 22 tooth part number 32743-36F22

A D21 JDM pickup uses a 23 tooth part number 32743-36F23

[ryguy]

Originally Posted by fuk240sx

any idea where I might be able to get a 23 tooth? or is there any way I can calculate how far off my speedo is so I know how fast I'm going on the highway atleast?

Use a GPS to get a reference point.

[fuk240sx]

Originally Posted by UNISA JECS

The CA18DE(T) AT uses a 22 tooth part number 32743-36F22

A D21 JDM pickup uses a 23 tooth part number 32743-36F23

Thanks ....

[auto_bot]

sorry to threadjack but did u use the r32 diff? if so what axles did u use in ur s13? the r32 has the 5 bolt pattern and i was trying to find if different axle stubbs can be installed into the diff or if all new axles are necessary. have tried searching but cant find solid responses. thanx for any input recieved.

[superJoy]

I used an HCR32 diff (GTSt m/t RB20DET I believe) and it came with the 5 bolt axles from the importer, so I just used those too.

I think if you want to use original 6 bolt axles, you need some of hte six bolt VLSD output shafts. That should work, no?

But 5 bolt axles are considered an "upgrade" because they're stronger or something, so I didn't really see any reason to find 6 bolt output shafts that worked. I just got the HCR32 diff + axles. (Both direct bolt in on S13, provided you aren't putting an ABS diff into nonABS car or vice versa) Was a really easy swap, and much cheaper than buying the R&P by itself. Of course it's used but whatever...

[swayray]

Originally Posted by racepar1

I LOVE my 4.36. It really livens up the stock ka and it doesn't rev too high on the freeway. I'm at about 3500 rpm at about 75mph. I'm considering the 4.6 though as the 4.36 made such a difference.

I guess the diameter of the wheel comes to play too... with my 4.36 i'm only able to do exactly 70 mph (based on my G-Tech Pro RR) at 3500 rpms but that's on a 235/40/17 size tire on a 17x9 wheel. The overall diameter of the wheel is about 24.5". My speedo is completely off and is showing that i'm doing about 85mph.

The 4.36 does liven up my stock KA... it pretty much allows me to shift sooner than with the stock 4.083. Gave me that bit of extra kick when i would exit turns last weekend's autox in el toro.

I'm not quite sure if it would work but the speed sensor gear off of an SR tranny that came with a 4.36 final gear might fix the speedo problem. I might just have to try that one first to see if it works.

[bec1488]

- - - - - - - - - -