B gearbox/LSD questions

[mooshie]

Ok so I am finally about to do something with the gearbox pieces I picked up a long time ago with the intention of installing onto my B18C turbo.
The plan is to fit hydro '98 Type R S80 internals into a YS1 casing to create a cable actuated R box to fit in a '91 Integra.

I have checked the tooth counts on the gears to confirm that they are from the right box-
Main. Counter. Ratio.
1st. 13. 42. 3.230
2nd. 19. 40. 2.105
3rd. 24. 35. 1.458
4th. 29. 30. 1.034
5th. 33. 26. 0.787

All ok there but the diff and final drive is a bit confusing. As you can see from the pics the final will need to be replaced but the tooth count on it is 14/68 giving a ratio of 4.857 instead of the OEM 4.785. I have counted multiple times so figure this must be an aftermarket final drive but does anyone know what it is?

The LSD diff also seems to sit into the YS1 casing comfortably but I haven't trimmed the internal ribbing yet, is there any way to confirm visibly or by other means what this diff is from? I am thinking it might actually be a optional LSD from a cable box, will this still fit and work ok with the other hydro internals?

Lastly, looking for opinions on what final drive to go for. The car will be heading to Mallala and Collingrove Hillclimb at least but I also like to go on a leisurely weekend drive in some of the open road 100kmh zones east of the Adelaide Hills. I have a S1 gearbox from an LS so could I fit the 0.742 5th gear in or will it not work with the other parts? The car has plenty of torque but the 4.7 sure is tempting instead of a 4.4 considering I hardly get out of 2nd in my standard b16 teg with a JDM J1 box at Collingrove.

And yes I will be going to Neat Gearboxes but wanted to share on here for the benefit of others too.

[chez00]

That does look like a factory LSD and if it is they are a very nice unit. I haven't worked out a way to distinguish between a few of the more common gear type LSDs, they all look pretty similar, and often people have no idea what they have in the first place. Sometimes they foul around the crown wheel bolts so you need to check the fit in both cases.

I honestly reckon the 4.9 is too short for Collingrove - traction from the steep start line will be difficult and you'll forever be changing between 2nd and 3rd with the extra power. I'd be chasing a hydro 4.4:1 personally. Mind you I know a fella with a turbo DC2 running 4.9 and is very quick around Mallala. There's always compromises - the setup requirements for collingrove are much different to mallala. Do you intend to get serious about a specific class of competition? If so, choose one or the other to build your setup around.

The cable .742 5th set doesn't work with the hydro main and countershafts. I have .714 hydro LS 5th ratio sets in stock if you want a more comfortable cruise, but not necessary unless you use the 4.9 or 4.785 FD.

[mooshie]

It's all just for fun at this stage not serious about competition, so 4.9 is really out of the question. The .714 sounds pretty good to go with the 4.7, any idea what revs that would be doing at 110kmh? For that matter I can't seem to find a clear answer on what revs the Type R is doing at that speed.. I'd be happy with anything under about 3900.

[mooshie]

So even if it is an LSD from a non Type R it will be fine? I figure it's the final drive that matters in relation to the rest of the gears anyway.

Forgive my gearbox noobiness but by crown wheel bolts do you mean the bolts in the pics above? And what would they foul on? I am aware I may need to trim down some of the internal ribbing in the case but it seemed to drop in and spin freely on the bearings (no seals etc in the casing) I just noticed that the bolts are installed on the opposite side of the diff from other pictures I have seen...

This style of bearing in the pic is normal for a Type R box too, as opposed to tapered roller bearings?

I have no reason to not believe what I was told when I purchased this stuff which was that it was all OEM aside from the final drive. Just looking for confirmation.

I probably wouldn't be able to get it down to you this week or next, so trying to figure out as much as possible now.

Thanks for the help.

[Adrian @ SAS]

My beer fueled recon is that the diff pictured is aftermarket clutch type for B16A (judging by inner diameter of ring gear)
OEM diffs have a removable speedo drive ring (bevel drive) where as diff pictured looks like cusco or spoon
Have Neat Gearboxes pull it down & see if ramps & pre load are adjustable

+ I also recon you'll be faster round the circuit if you use 1.107 4th & 0.875 5th with 4.4 final as above

My 5cents on ring gear...
Aftermarket ring gear miss-matched with OEM counter shaft
EG: MF 4.0 - 68/17
Would kinda explain the missing teeth too (& the tooth cut)

Re mix 'n match,
best go to neat as there are a variety of different shaft diameters & bearing sizes across the cable models
some you can do it, some you can't & selectors can also be an issue

Uuuurp!

[mooshie]

Thanks, even full of beer you can relate good info!

You also raised an interesting point with the speedo ring gear. On the DA the VSS drives a cable to the back of the cluster but this VSS won't go into the casing with the LSD in place, the splines are a lot bigger than the electric VSS for the hydro box(test fitted also and seemed to turn no worries)

What do I do for a speedo reading? I couldn't find anything on the net...

[chez00]

Great info Adrian, thanks. I forgot about the removable ring.

The enclosed diff bearings in the pic are later hydro bearings. You can use them in place of the tapered rollers, the shims just change around.

crown wheel bolts are the ones holding the large ring gear to the LSD.

I'm unsure on the speedo drive - later hydro were electric but seem to remember there were early hydro cable driven? Someone should be able to pitch in. It may need a cluster swap?

[dougie_504]

I've gone for the cable 5th from the LS (the 0.742) to mate to my 4.9FD in my EF8. Will hopefully be up and running soon if you want some feedback.

Personally I'd say go with the 4.4 if you're going to be doing some highway driving otherwise you'll probably be cruising at quite high RPM. You're running an F/I setup so it's fine to have a little length in the gears.

You might be faster around a track if you go 4.7 and run the shorter 5th but your day-to-day driving will be a total suckhole.

[Adrian @ SAS]

Re diff, final drive ring gear bolts are also not OEM left hand thread.
As for speedo drive, you're going to have to figure out what brand the diff is & buy their brass bevel gear to replace the OEM one held in the drive by a cotter pin (mechanical or electric)
Normally this comes with the diff...
Looks like this...

[Adrian @ SAS]

More 5 cents worth...
B18C final drive ring gear inner diameter is 116.8mm (10 bolts)
B16a final drive ring gear inner diameter is 109.0mm (10 bolts)
Also, my best guess is your LSD is either KAAZ or MFactory

[mooshie]

Awesome info here. Have to say that pic looks a lot like my diff- is that an Mfactory or KAAZ? even if I have to get a couple of those gears for the VSS I'm sure they shouldn't be too expensive. Considering all this stuff cost me less than about $500 (got a heap of other gear in the deal) I think I'm doing ok so far for the hassle.

Will take a couple of measurements soon. Oh and I tested the clearance I the housing again and this time pushed the casing back together roughly, then I spun the diff it was contacting something so that's a good sign it's a later hydro diff as well. I'll trim the ribs over the weekend and clean it up a bit.

Edit- just thought, in all likelihood the gear drive in the electric VSS that came with the setup is probably correct for this LSD... There was a cable one as well so I have a spare I can play with and see if I can get to work.

[Adrian @ SAS]

Diff pictured is KAAZ 1.5way. (only comes in 1.5way)
MFactory looks the same but is available in 1.0 / 1.5 / 2.0 way
You'll need Neat to confirm... (way too much typing to explain ramps)
The fouling is likely the ring gear retaining bolts fouling on the case below.
(You'll need to clearance this + shim it correctly)

Also, the diff pictured above is a clutch type. OEM torsen types have cast in dirt pig iron outer shell. (see below)