close ratio trans

[rioredstang]

Has anybody used a OS GIKEN close ratio gear set? Will they fit stock shafts? What else is available for a KA.

[a250gpguy]

I was under the impression that many different granny will hook up with the right bellhousing. Since you mentioned the OS Giken kit another expensive option would be the Nismo 6 speed unit...

Cheers,
Ch
Sent from my NookColor using Tapatalk

[KA240SX808]

OS kit will fit the stock shaft. They just offer a stronger one for those making alot of power.

The Nismo 6-Speed is only for SR's so you'll need an adapter or custom housing.

[Tower240sx]

for the KA the RB25 trans is a close enough fit some people are willing to get away with bolting it up directly,

The problem with the stock trans is as much one of case and shaft strength as it is a gearset issue, it is much cheaper to change transmissions than to try and address the short comings of the stock unit

[CodyAce]

Find a 4.9 out of an Xterra front diff and slap it in.

[240sxTTC]

I use the 4.9 FD and it's great for my higher reving KA. 3rd and 4th gears are just about perfect for Mid-OH but 5th gear in the KA trans still sucks; way too tall.

[Matt93SE]

A 4.9?!?! Fawk.. the 4.6 is already too short for what I need. I was considering going to a 3.9 or a 3.6 and running a gear lower...
If you go to a dog box, VERY few run an overdrive in them, so I need to set up my diff gearing to work with a 1:1 top gear.
Either that or find the proper $$$$$ 5 spd dog box w/ overdrive.

You can also do it with a Jerico 4 spd by flipping the shift lever for 3rd and 4th.. then 3rd gear becomes the straight-thru 1:1 and 4th can be an overdrive. But that gives you almost nothing down low. 1st gear would have to be a track gear taller than 2nd to get any benefit out of it.

For you guys still running KA trannies, you can also use the 5th gear from a HArdbody truck. it's shorter than the S-chassis 5th gear and is much better for racing.

[240sxTTC]

A 4.9?!?! Fawk.. the 4.6 is already too short for what I need. I was considering going to a 3.9 or a 3.6 and running a gear lower...
If you go to a dog box, VERY few run an overdrive in them, so I need to set up my diff gearing to work with a 1:1 top gear.
Either that or find the proper $$$$$ 5 spd dog box w/ overdrive.

You can also do it with a Jerico 4 spd by flipping the shift lever for 3rd and 4th.. then 3rd gear becomes the straight-thru 1:1 and 4th can be an overdrive. But that gives you almost nothing down low. 1st gear would have to be a track gear taller than 2nd to get any benefit out of it.

For you guys still running KA trannies, you can also use the 5th gear from a HArdbody truck. it's shorter than the S-chassis 5th gear and is much better for racing.

I think the Hardbody is the same fifth gear ratio (0.838) as the SR20DET??

The KA is 0.759....booooo!

The vehicle speed for the 0.759 ratio at 7500rpm with a 24.50" diameter tire is 147.0mph and with the 0.838 is 133mph, which is perfect for Mid-OH but may be an issue for higher speed tracks like Road America. For those instances I would switch to my 4.63 FD, which increase top speed to 141mph.

[Matt93SE]

Yeah, the D21 has a 0.838 5th gear.

The problem with the 4.6 and stock ratio .759 is that I redline 4th with my 4.08 at the end of the straights at MSR-Houston. When I go to the 4.6, I have to shift into 5th about halfway down the straight.

.759 * 4.6 = 3.51 overall
1.000 * 4.08 = 4.08 overall

I lose 15% more torque by using the 4.6 in 5th gear than I do by keeping the 4.08 and staying in 4th gear.

I come off the corner in the meat of 3rd gear, but I'm still getting pulled at the end of the straights by Miatae. doh.

Cost me 3 sec/lap going to the 4.6!!

[KA240SX808]

IIRC for the HB/Frontier
4x4 = .821
2wd = .838

[240sxTTC]

Yeah, the D21 has a 0.838 5th gear.

The problem with the 4.6 and stock ratio .759 is that I redline 4th with my 4.08 at the end of the straights at MSR-Houston. When I go to the 4.6, I have to shift into 5th about halfway down the straight.

.759 * 4.6 = 3.51 overall
1.000 * 4.08 = 4.08 overall

I lose 15% more torque by using the 4.6 in 5th gear than I do by keeping the 4.08 and staying in 4th gear.

I come off the corner in the meat of 3rd gear, but I'm still getting pulled at the end of the straights by Miatae. doh.

Cost me 3 sec/lap going to the 4.6!!

I agree......the KA 5th gear ratio is a dog. I shift into fifth and the car feels like it stops accelerating. If you rev'd your KA higher the shorter FD's would actually help compared to the 4.08 with the stock trans. So what FD are you going to use and what trans or are you still figuring?

[Matt93SE]

Hmm.. it lost my last post..
I'm still looking for a Saenz 840 dog box. Maybe a G Force or Jerico 5 spd as well. Almost all of the 4 spds are a 1:1 4th gear, which would require me to have a tall final drive and finding those for an R200 is pretty fun.

If I run an overdrive 5 spd, I can use the drop gear to keep the car in its happy place vs. changing out rear diffs.

Changing a drop gear takes quite a bit less time, but you still have to pull the driveshaft and some other stuff off to get to it.

[Tower240sx]

which tranny are you looking at that has a drop gear setup already?

[CodyAce]

I agree......the KA 5th gear ratio is a dog. I shift into fifth and the car feels like it stops accelerating. If you rev'd your KA higher the shorter FD's would actually help compared to the 4.08 with the stock trans. So what FD are you going to use and what trans or are you still figuring?

Haha it's like 5th gear in a stock VE FWDer....you plop it into 5th and it just kinda 'stays there'....frutrating to say the least.

[Matt93SE]

which tranny are you looking at that has a drop gear setup already?

Almost all of them I'm looking at have a drop gear...

[Def]

I agree......the KA 5th gear ratio is a dog. I shift into fifth and the car feels like it stops accelerating. If you rev'd your KA higher the shorter FD's would actually help compared to the 4.08 with the stock trans. So what FD are you going to use and what trans or are you still figuring?

The SR20DET trans has a 0.759 5th - it's horrid. You shift into 5th and it's got nothing...

Can you swap the SR bellhousing onto a D21 trans just like the KA/SR bellhousing swap? A .838 5th would be very nice for TWS, being about 10% shorter.

[Matt93SE]

The 240 racers just swap the 5th gear itself.
It's the same tranny internally, so I don't see why you couldn't swap an SR bellhousing onto the front of it as well.

be sure to leave the 3' long shifter on it too. :)

[240sxTTC]

The SR20DET trans has a 0.759 5th - it's horrid. You shift into 5th and it's got nothing...

Can you swap the SR bellhousing onto a D21 trans just like the KA/SR bellhousing swap? A .838 5th would be very nice for TWS, being about 10% shorter.

I thought the SR20DET trans has the 0.838 fifth?? Maybe it's only the S14.


Update: found an S14 service manual and fifth is 0.838. The S13 appears to have the same 0.759 as the KA. I also found an S13 CA18DET manual and except Europe has 0.838 and Europe has 0.821.

Also found below info:

All KA's SOHC and DOHC
1st = 3.321
2nd= 1.902
3rd = 1.308
4th = 1.000 (Direct Drive)
5th = 0.759 (Over Drive)


All S13 SR20DET's
1st = 3.321
2nd= 1.902
3rd = 1.308
4th = 1.000 (Direct Drive)
5th = 0.759 (Over Drive)


All S14 SR20DET's
1st = 3.321
2nd= 1.902
3rd = 1.308
4th = 1.000 (Direct Drive)
5th = 0.838 (Over Drive)


All JDM CA18DET's
1st = 3.321
2nd= 1.902
3rd = 1.308
4th = 1.000 (Direct Drive)
5th = 0.838 (Over Drive)


All Euro CA18DET's
1st = 3.592
2nd= 2.057
3rd = 1.361
4th = 1.000 (Direct Drive)
5th = 0.821 (Over Drive)


KA24 4WD Trucks (Hardbody's/Frontiers)
1st = 3.985
2nd = 2.246
3rd = 1.415
4th = 1.000 (Direct Drive)
5th = 0.821 (Over Drive)

KA24 2WD Trucks (Hardbody's/Frontiers) - 1997
1st = 3.985
2nd = 2.246
3rd = 1.415
4th = 1.000 (Direct Drive)
5th = 0.838 (Over Drive)

[KA240SX808]

^You found my secret stash :p j/k

I actually plan on running a hybrid Trans w/ a:

3.321
2.057
1.361
1.000
And maybe a .821

The SR20DE (N/A Silvia's) IIRC also use the Euro CA18 Gears

[McCoy]

The SR20DE (N/A Silvia's) IIRC also use the Euro CA18 Gears
I can confirm this one as I'm running it and really really like it... especially with the 4.6 :)

[240sxTTC]

I can confirm this one as I'm running it and really really like it... especially with the 4.6 :)

Are you running the whole trans or did you replace 5th on yours? If you did replace 5th gear, can it be removed from the rear of the trans w/o taking the whole gear cluster out? I thought reverse and 5th are accessible from the rear of the trans. Thanks.

[McCoy]

I'm running the SR20DE tranny, as my car came with an SR20DE swap done by the previous owner. I got the distributor to prove it, lol.

[240sxTTC]

I'm running the SR20DE tranny, as my car came with an SR20DE swap done by the previous owner. I got the distributor to prove it, lol.

Nice!

[KA240SX808]

I don't know of any way of access from the back of the Trans. I only know of splitting the case to gain internal access.

[Umai Kakudo]

Another $$$$$$$ option for beefed up internals for the FS5W71C case is the Ikeya Formula setup

Price - H Pattern - $7,700 - "Sequential" - $9,000 + Shipping from Japan.

http://www.ikeya-f.co.jp/en/product_notice/mission_parts.html#fs5w71c

1st　 2.711　
2nd　1.799　
3rd 1.288　
4th　1.000　
5th　0.812　

http://www.ikeya-f.co.jp/ja/car_type/images/dogmt/dog-zentai.gif

http://www.ikeya-f.co.jp/en/car_type/dogmt/dog-mainshaft-hikaku2-en.jpg

The advantage to using the fs5w71c over the Z32 or Z33 transmissions is easier service due to smaller case size and about 15 to 20 lbs.

I know a local FD driver who bought the sequential setup. He broke the U joint on the drive shaft the first event and then blew up 2nd gear (broke off all the teeth) the second event. Had to airfreight parts from JP to get ready for the next event. Not strong enough for a drag/drift car but it should take road racing.

[240sxTTC]

Good info but no way would I spend that kind of money on the KA trans. If I had that kind of money laying around for a gear set, I probably wouldn't be tracking a 240sx. :)

[Bubba]

I'm going to be using the Z32 transmission after I finish my KA-t build. Anyone have any opinions on that setup VS the KA tranny options?

Aside from size and weight as stated above that is...

[Matt93SE]

For the price of that Ikeya headset, you can buy a used WORLD CLASS sequential like a houseman or saenz box.

Bubba, the gearing in the z32 tranny is nearly identical to the s-chassis box. Acceleration will be same but the z box is a lot stronger.

Sent from my MB860 using Tapatalk

[Bubba]

Thanks, luckily for me the strength increase is about all I really need. I'm not looking to compete for rank, just looking for the strength and a little fun.

[PerilousActs]

For the price of that Ikeya headset, you can buy a used WORLD CLASS sequential like a houseman or saenz box.

Bubba, the gearing in the z32 tranny is nearly identical to the s-chassis box. Acceleration will be same but the z box is a lot stronger.

Sent from my MB860 using Tapatalk

Where you finding these used houseman and saenz boxes? I haven't seen any pop up in a while. Looking to acquire one before April if possible.

[Matt93SE]

Im on the hunt too. Will tell you when I find one. ;)

[rioredstang]

Let me see, If I use a D21 transmission and then use the os giken 2nd gear kit, I would have these ratio.
1st-3.21
2nd-1.722
3rd-1.308
4th- 1.1
5th-.838
This is not that bad, and cost may be doable. What do you think?

Here is a comparision between a stock trans with a 4.08 and updated D21 with 4.63
Transmission One stock
Gear
Ratio Max MPH
1st Gear :1.321 36.41 MPH
2nd Gear :1.902 63.57 MPH
3rd Gear :1.308 92.44 MPH
4th Gear :1.1 120.92 MPH
5th Gear :.759 159.31 MPH
Final Drive 4:08

Transmission Two updated D21
Ratio Max MPH
1st Gear :1.321 33.19 MPH
2nd Gear :1.722 61.88 MPH
3rd Gear :1.308 81.46 MPH
4th Gear :1.1 96.86 MPH
5th Gear :.838 127.15 MPH
Final Drive 4.63:

[Def]

4th gear is 1:1, so just 1 in your calcs.


The slightly shorter D21 3rd and 5th does sound nice, but the last thing my car needs is a shorter 1st and 2nd with the 4.36 out back.

How much of a PITA is it to get inside a KA/SR trans? I probably wouldn't mind freshening up some synchros (like 2,3,4) while I was at it and maybe change the 5th gear out.

But I'm guessing as with most things trans related it's just easier to buy a complete one and hope it's in good shape.

[PerilousActs]

Im on the hunt too. Will tell you when I find one. ;)

Just missed out on a 5 speed Saenz SP910 that I just found on sccaforums by a week. fml.

There's a 3 speed SP-910 on racingjunk if anyone is interested. Not sure if it can be converted to 5 speed or if the 3 speed is a special case.

[TunedBy]

I don't know if the 5speed SR geabox bolts to the KA engine, but to get a close ratio in my datsun (had an s13 sr20 in it) we took the s15 6 speed, machined off 20mm from the front of the bell housing. Got some different length bolts, modified the gearbox mount and got a longer tailshaft.

the car had never felt more alive!

i would love to do the same to my 180sx but need to do brakes + suspension first.

[KA240SX808]

On a KA to use SR gear box you gatta swap the Bellhousings. IDK if the S15 SR Housing can be swapped for the KA.

[Tower240sx]

you can't swap the bell housings on the s15 6-speed with any KA bellhousings, besides you don't want that tranny it's a decrease in tq holding.

DEF, the 5 speeds are as simple as they come and cheap enough that once you get in there, if you are in over your head you throw it away, just start with a trans that needs syncros so you aren't destroying a good trans, I have a box of FS5w71 trans parts i have "learned" on and several good trans I rebuilt running around socal.

[Umai Kakudo]

FYI here is the best info on the bolt in Kit that NISMO offers (Plus info on the Nismo GT LSD Pro).

Official Nismo JP Page - http://www.nismo.co.jp/en/products/competition/mission/silvia.html


PDF - Price List with good gear ratio graphs - http://www.nismo.co.jp/en/products/competition/mission/pdf/silvia_price.pdf
PDF - Replacement Parts Price list - http://www.nismo.co.jp/en/products/competition/mission/pdf/silvia_spec.pdf


Modified Mag Article - http://www.modified.com/tech/sccp_0903_project_s13_part_3/viewall.html

Notes:

350,000 Yen / $4,550 USD
Full Bolt On Kit to put the Nismo modified FS6R92A behind a S13 or S14 block in its matching chassis (minus required S15 clutch and flywheel).
Must use the S15 clutch and flywheel with the transmission.
OEM / NISMO quality parts and kit completeness.
Includes a standard S13 or S14 speed sensor mount to make the speedo plug and play.
Modified and more aggressive gearing compared to the Stock S15 transmission with slightly strengthened gears.
S13/S15 5 Speed (FS5W71C) and S15 Silvia Spec R six-speed (FS6R92A) is rated for 217 lb-ft of torque (source Modified)
Nismo six-speed is rated for 289 lb-ft of torque, thanks to gearing and gear diameter changes (source Modified)
Nismo lists capacities of the Nismo cross mission as: engine torque design value: 40kgfm (392N•m)( 289.09 ft-lb) and engine power: 350ps (257kW)(344.64 hp).


http://www.nismo.co.jp/en/products/competition/mission/img/silvia/img_graph1_en.gif

http://image.modified.com/f/15603695/sccp_0903_09_z+project_s13+gear_ratios.jpg

http://image.modified.com/f/15603887+w750+st0/sccp_0903_02_z+project_s13+nismo_transmission.jpg

http://image.modified.com/f/17373502+w750+st0/sccp_0903_03_z+project_s13+old_and_new_transmissio n.jpg

This is where Nismo steps in. Starting with the FS6R92A S15 six-speed transmission casing, Nismo fits a custom reinforced gearset and adds a mechanical speedometer drive gear to the mix. Nismo reinforced six-speed transmissions come fully assembled from JDM Power so we didn't bother tearing the gearbox apart to cryo-treat or coat the gears. JDM Power sells the complete Nismo bolt-in kit, which also includes the transmission mount, driveshaft, shifter, hardware, and required harness extensions. The only other items you'll need are an S15 clutch, new shift knob (five-speeds use a 10x1.25 thread, six-speeds are 12x1.25), and gear oil. Unhappy with all the burning hot aluminum and titanium shift knobs on the market, we had our rubber Nissan shift knob machined out to 12mm.

Transmission
Nismo reinforced cross six-speed 91.6 pounds
Stock five-speed 95.4 pounds

Nismo offers the reinforced six-speed transmission with a multitude of kits to make it a direct bolt-in installation into any S13, S14, or S15 equipped with an SR20DET or SR20DE engine. If you own an S13 or S14, you'll need to swap over to an S15 clutch at the same time just like we did because of the difference in reach between transmission input shafts. The S15 flywheel, pressure plate, and clutch will directly bolt on to any SR20DET engine.

. . . .

Nismo claims to have reinforced this transmission over a stock S15 six-speed through the use of larger-diameter gears and by changing most of the gear ratios versus the standard S15 box. For Fifth gear, which is the same as the standard S15 (1.000), Nismo has reduced the number of both counter and main gear teeth and has increased the size of the gear teeth. First gear for Project S13 is now noticeably taller (numerically lower), with the new gearing helping to cushion the launch shock load from a standstill. One of the biggest advantages with the Nismo six-speed though is how Second, Third, and Fourth gears have all been moved closer to each other, which helps us stay above the boost threshold when on track.


This could be an expensive option for a street / HDPE car with mild power goals.

The gearing comparison is interesting and may be helpful to assist with home brew gearing schemes.

[niceguy]

This may not be of much help or interest but one member bought a gear set from PAR for his turbo first gen ('93-97) Altima, which were heat/cryo treated...

There's a couple of pics but not sure of price. If I find out I'll post back...

http://www.nissanclub.com/forums/forced-induction-forum-turbo-sc-tuning/232323-coming-along-30.html

[rioredstang]

Just got my .838 gear kit from WIT Transmissions today. Now the disassembly begins. Not a bad price. $95.00 shipped. I will let you know how it goes.

[Def]

Please post up a DIY if you tear into that sucker. Especially if you find ways around "special tools" that trans work always seems to call for.

Does the kit come with a new synchro? Or just the gears themselves?

[a250gpguy]

+ 1 on Defs DIY suggestion!

Sent from my DROID RAZR using Tapatalk

[rioredstang]

It only came with the gears. I am going to call back for the and see if they have synchro kit.

[a250gpguy]

Does anyone here know if there's an adapter kit to fit the T56 tranny to the s chassis....what's the weight / size like compared to our 5 and / or 6 speed units (s15, z33 etc.)?

Sent from my DROID RAZR using Tapatalk

[Matt93SE]

Doesn't the T56 mount to a standard T5-type bellhousing mount?
from what I understand for the guys running dog boxes and such, they use a 280zx auto bellhousing.. not sure if it bolts on without mods, or if it needs work to fit.

[PerilousActs]

I saw an adapter on some Aussie site a few months ago, but iirc the company stopped producing them.

Bill @ dsg made an adapter plate and welded it onto a cut up stock bell housing I believe for his T5. Pics are probably on his site.

[Matt93SE]

Yeah, that's the "easy" solution. take a blowed up tranny and cut the bellhousing up and weld an adapter plate onto it. must be done by competent machine shop, but is regularly done.

If the L28 bellhousing bolts up to the KA, that makes like a LOT easier.

[Preston]

I'll be rebuilding (attempting ;)) my s13 KA trans this winter...I'll let you guys know how it goes...and I'll be doing it without "special tools"...keep you all posted.

[DeepSeaDynamo]

Yeah, that's the "easy" solution. take a blowed up tranny and cut the bellhousing up and weld an adapter plate onto it. must be done by competent machine shop, but is regularly done.

If the L28 bellhousing bolts up to the KA, that makes like a LOT easier.

FYI the KA auto trans uses a bolt on bell housing.

[Matt93SE]

And of course I threw away my KA auto a couple years ago.. :\

[djsilver]

And of course I threw away my KA auto a couple years ago.. :\

Me too :(

[Tower240sx]

yeah so they are everywhere for free or cheap no one likes them or uses them

[Def]

yeah so they are everywhere for free or cheap no one likes them or uses them

But as soon as you want it the price jumps by a couple hundred.

[Epstein]

I've got an S14 KA auto trans stashed in N Atlanta. Anyone out there want to pick it up for free?

[djsilver]

I've got an S14 KA auto trans stashIed in N Atlanta. Anyone out there want to pick it up for free?


I'll take it. I have a brother-in-law in Cartersville. I'll check with him and make arrangements.

[rioredstang]

I was looking at some other transmissions and saw Honda S2000 6 speed. I would have to make bellhousing and drive shaft to work, but look at these ratio's. S2000 has bhp237 so I think it would handle NA motors. I saw several on flebay 600. Just something to think about.

1st Gear :3.133 36.12 MPH
2nd Gear :2.045 55.33 MPH
3rd Gear :1.481 76.4 MPH
4th Gear :1.161 97.46 MPH
5th Gear :.970 116.65 MPH
6th Gear :.810 139.69 MPH
Final Drive :4.36

Transmission Two
1st Gear :1 34.01 MPH
2nd Gear :1 52.1 MPH
3rd Gear :1 71.95 MPH
4th Gear :1 91.78 MPH
5th Gear :1 109.85 MPH
6th Gear :1 131.55 MPH
Final Drive :4.63

[hai1206vn]

^ Not sure where you got 4.36 or 4.63 from. I'm sure the final drive (R&P) ratio is 4.1. But, on top of that there's a primary gear reduction of 1.160 (AP1) or 1.208 (AP2). This makes the final drive effectively 4.756 (AP1) and 4.953 (AP2).

Those ratios are way too low if you can't rev to 8.5-9k.

[Def]

^ Not sure where you got 4.36 or 4.63 from. I'm sure the final drive (R&P) ratio is 4.1. But, on top of that there's a primary gear reduction of 1.160 (AP1) or 1.208 (AP2). This makes the final drive effectively 4.756 (AP1) and 4.953 (AP2).

Those ratios are way too low if you can't rev to 8.5-9k.

How do they do that? With another main/countershaft?

[rioredstang]

So then, if we have a gear reduction of 1.16 we could run a 3.73 or 3.91 r&p. Then our rear gear would run much cooler and take less power to turn. Is this right or am I thinking all wrong. The F20c has a internal pump to help lube the trans. also carbon synchros for better shifting.

[hai1206vn]

The 240 tranny has the input shaft coming in (FSM calls it main drive gear), driving a countershaft, which drives the output shaft (FSM calls mainshaft). The mainshaft & countershaft carry all the gears. The input shaft & output shaft line up in 1 axis but can spin independently.

The s2000 tranny has it kinda opposite, where the mainshaft (also input) & countershaft with all the gears meet up first, which means the output is off axis. Then at the very end of the countershaft there's a "secondary drive gear" which mates with another gear on a separate "secondary shaft", which lines up with the mainshaft axis. It's the secondary drive gear and secondary shaft that give the primary reduction ratio. This secondary shaft leaves the tranny as the external output.

From the pics I've seen, 1 reason why the s2000 tranny may be so smooth is that the gears are rather small. All 6 pairs of gears are crammed into the middle section in this pic (http://chaboud.smugmug.com/Other/s2k-tranny/IMG20110417190357/1255809846_bS6ZHcw-M.jpg). So it's really FWD-sized gears sitting in a RWD box. Smaller gears, less momentum.

[Matt93SE]

If they're that small, that also means the gears are relatively weak.

The other good thing about that is that it's easy to change drive ratios. you may have to pull the tranny apart, but you can swap that secondary drive gear (it's called a "drop gear" race trannies), and change your final drive pretty easy. Those gears are about $100 each on the used market for Jericos and such, and you can fit half a dozen sets in a shoe box. WAY easier to change out than a R&P, and you don't need 6 diffs to make it a quick change either.

[rioredstang]

The gears are smaller, but would they last with a NA motor. I didn't think this would ever last behind a turbo. For us road racers that don't abuse our gear box it might work. The percentage of drop between gears look good.

[Def]

If this is going behind an NA KA I think you'd be better suited with some wider gears. There's a pretty broad powerband, might as well use it vs. having to row the gearbox constantly and end up going slower.

[DeepSeaDynamo]

Here is an interesting thread about using a 350z trans

http://www.ka-t.org/forums/viewtopic.php?t=50769&postdays=0&postorder=asc&start=0

[Umai Kakudo]

Looks like OS Giken is working on making a universal transmission case / bell housing adapter for the Z33 transmission.

http://osgiken.bizon.jp/os_high_speed_blog/2011/10/media-coverage-by-option2-magazine.html

Option2 magazine (one of the well-known auto magazines in Japan) has visited our office to cover new products from OS Giken.karaoke

They have asked for a new product, so we prepared Street Master clutch (Grand Turing for the international market) for them, but they some how and some where heard that we are currently developing an universal 6spd transmission, and wanted to cover it as well...coldsweats01

We were hesitant of it going public so soon since it was still in the development, but the mighty big-boss said "do it",so we done it.

The magazine staff is taking pictures of the 6spd transmission below

It's coming along quite nicely, don't you think?
This unit was equipped with a bell housing for SR20DET. It will move onto a testing phase very soon by installing it to a test vehicle.

The basic structure of this universal transmission is a main case + a bracket + a bell housing. The main case was designed to fit any bell housings by replacing the bracket.

http://osgiken.bizon.jp/os_high_speed_blog/images/2011/10/24/option2.jpg

https://www.facebook.com/photo.php?fbid=10150305375280198&set=a.269927795197.317121.217131310197&type=3&theater
https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash2/74262_10150305375280198_217131310197_15778447_7747 778_n.jpg

Might be a good street car option that needs syncros and want to be able to easily switch engines in the future.

[PerilousActs]

That's soooo gonna cost $10k or more. :(

[Umai Kakudo]

Looks like Quicktime has made VQ to T56 bell housings in the past.

http://www.motoiq.com/magazine_articles/id/2074/pageid/3448/kns-super-unlimited-infiniti-g35-circuit-battle-slayer.aspx

From MotoIQ K&N G35 TA article:

A Tilton 5 inch triple metallic disc clutch with a super lightweight flywheel keeps the moment of inertia low for quick acceleration and fast shifts. The transmission choice is really unusual. The Nissan transmission has been scrapped for a Borg Warner T56 six speed transmission modified by Liberty Transmission using their Proshift modifications. Proshift removes the transmission's syncros and replaces them with what looks like dog rings Thus you can have the fast shifting of a dog type transmission without the high cost associated with one.

I'm pretty sure Quicktime also has made bellhousings for other Nissan engines legal for the GT class cars (KA, L, VG, VQ).

That would indicate they cold make bellhousings for all the US market engines to mount to any popular domestic performance transmissions. If some one wanted to bite the bullet I'm betting the would do an SR bellhousing as well.

Liberty Transmissions will also for a reasonable cost (~$2K depending on options if I remember right) modify any transmission (I know they've done Z32's for a friend) with their proshift setup (replace syncros with dog engagement style rings, modify and strengthen OE gears, and even remove gears (5th/6th) for lower inertia)

The proshift treatment is going to be the lowest cost setup for an OEM box to make it as strong as possible before stepping up to a beadspoke racing transmission.

[Preston]

Just an update...got my s13 KA trans torn completely down. To those who ask about special tools...NONE needed...need sockets, wrenches, snap ring pliers, a puller, a bearing splitter/separator, and a shop press. Follow instructions, and it's quite easy. I'll keep updating as I rebuild.

[Umai Kakudo]

Cool!

I need to get off my ass and build my custom engine stand adapter to mount the transmission center plate to for rebuilding fun, then get to it myself.

[Preston]

Didn't even do that...just had paper towels on the work table and made sure as I was doing stuff I wasn't letting anything get damaged...when you don't have a full fledged shop at home...you make do ;)

[Preston]

Should have the gearset back together tomorrow, and finish up and in the car this week.

NOTES: Take LOTS of pictures and go slow...I had to backup and redo a few things because I reintalled wrong, only caught it because I've been double and triple checking my work. No fatal issues *yet*, but we'll see if she runs...although I don't see why it wouldn't.

[Matt93SE]

friendly suggestion... once you put the case back together, put the tranny in every gear and rotate input shaft by hand to make sure everything works BEFORE you stick it in the car and have the torque of a running engine behind a gear shift. had a friend get something wrong with the shift linkage setup in a tranny and it stuck in two gears at once at about 2500rpm on his test drive. he heard a big bang and then marbles... ouch.

[Tower240sx]

+1 for matt's suggestion,

[Umai Kakudo]

Found this cool reference for older Datsun FS5C71A/B transmission gear ratios:

http://gracieland.org/cars/techtalk/gearing2.html

Of note are the ratios for the old Nissan Comp FS5C71* transmissions (hit the link for a better formatted table).


Nismo W/R OD FS5C71B 5 spd "B" type 3.321 2.077/37% 1.308/37% 1/24% 0.864/14%
Nismo C/R OD FS5C71B 5 spd "B" type 2.906 1.902/34% 1.308/31% 1/24% 0.864/14%
Nismo Opt 1 DD F5C71B 5 spd "B" type 2.818 1.973/30% 1.47/25% 1.192/19% 1/16%
Nismo Opt 2 DD F5C71B 5 spd "B" type 2.348 1.601/32% 1.296/19% 1.138/12% 1/12%
Nismo Opt 3 DD F5C71B 5 spd "B" type 2.192 1.601/27% 1.47/8% 1.138/23% 1/12%
Nismo Rally DD F5C71B 5 spd "B" type 3.321 2.27/32% 1.601/29% 1.24/22% 1/19%
Nismo Ultra C/R FS5C71A 5 spd "A" type 1.858 1.388/25% 1.217/12% 1/18% 0.852/15%
Nismo Middle C/R FS5C71A 5 spd "A" type 2.678 1.704/36% 1.262/26% 1/21% 0.852/15%



Abbreviations

F - Type of control F=Floor (direct) R= Remote
S - Tranny style S=special overdrive top gear (no letter indicates direct drive top gear)
C/R=close ratio 5 - Number of forward gears 3 spd, 4 spd, or 5 spd
W/R=wide ratio C - Drive/Synchro type F=front wheel drive R= rear wheel drive W= Warner synchros C=servo synchros
OD=overdrive 71 - Gear-pair center-to-center spacing in mm (distance between mainshaft and countershaft)
DD=Direct drive A - Sequential model version suffix (alphabetical) "A" type - shifters are rubber mounted (infamous monkey motion) "B" type - shifters have a solid cross pin
"C" type - shifters are retained in a top cover plate by a circlip (called a "top loader" in American trannys)