How much power can a W model gearbox take

sxymr2 · Post by **sxymr2** » Thu May 03, 2007 3:12 pm

I have a 20b powered mazda rx7 making just over 500rwhp, however as anyone who ownes a mazda know they cant make a good gearbox to save then self

A lot of people talk aboult the toyota W and R gearboxes however i cant not find any info abult how much power they can take.

Im on my 3rd mazda gearbox now which are only good for the 300 rwhp mark

l1ttle_d3vil · Post by **l1ttle_d3vil** » Thu May 03, 2007 3:58 pm

i dont know actual figures but ive seen a 4agte which is putting out around 150kw go through about four t50 gearboxes (which are reasonably strong), put a w55 in and its never had a problem in over a year.

deaf_rattle · Post by **deaf_rattle** » Thu May 03, 2007 5:53 pm

its not the power that kills the w boxes, its the torque.
id go for an r154 with that sort of power

postfach · Post by **postfach** » Thu May 03, 2007 6:12 pm

deaf_rattle wrote:its not the power that kills the w boxes, its the torque.
id go for an r154 with that sort of power

I second that. My W box is taking 300whp just fine but add another 200 to that and I would imagine that it would become unhappy. R154 FTW

matt dunn · Post by **matt dunn** » Thu May 03, 2007 6:38 pm

My car is around 300hp and has never had a problem with the box taking the power.

Our old 1JZGTE made estimated around 450hp and lots of torque,
and a W55 lasted on average 3 race meetings before it stripped the input shaft of all the teeth.

strx7 · Post by **strx7** » Thu May 03, 2007 7:45 pm

Its Torque at RPM is what seems to make rotary's eat gearboxes.

A S4/5/6 gearbox would handle a 20B it just depends how you drive it and how much traction you have....

evil_si · Post by **evil_si** » Thu May 03, 2007 8:46 pm

series 6 box's dont handle 13b's very well id hate to think what a 20b would do,

a mate had a 6 speed, getrag box behind a 20b in his fd race car, handled it nicely, pity about the price tag thou

KinLoud · Post by **KinLoud** » Thu May 03, 2007 9:26 pm

What kills gearboxes - stress x repetition
So low torque = long life
High torque shorter life

What sort of use?
Drag = very short life (big clutch dumps, solid centre clutch, big grippy tyres)
Drift = short (clutch dumps, clutch kicks, way less grip than drags)
Track = medium to short life (in some ways kinder starts than drags)
Street = depends entirely on your driving habits

Talk to Matt Dunn - he has good knowledge of a big horsepower 2jzgte? in a racecar that would chew a W55? gearbox every 4th raceday i think.

Ken
Ham
021 408 863

suckymotor · Post by **suckymotor** » Fri May 04, 2007 8:12 pm

the xjs jag kills them very easy

sxymr2 · Post by **sxymr2** » Sat May 05, 2007 12:16 pm

well im using it for street and weekend drags.
hmm looks like i may be looking at a R series box, anyone have any idear how much im looking at for one?

a 20b is a very High torque motor made to pull big jc cosmo's around.

sxymr2 · Post by **sxymr2** » Tue May 08, 2007 7:27 pm

i was also looking around some part numbers and i see a v160 box is 6 speed and used by some late model supra's

i have seen a rotary brake the bellhousing off a w57 box before so they much take a bit

strx7 · Post by **strx7** » Tue May 08, 2007 7:36 pm

$4K for a V160 IF you can find one, and the bell housing is all one piece with the front of the gearbox

sxymr2 · Post by **sxymr2** » Tue May 08, 2007 8:34 pm

dam o well if its bell housing and gearbox are not removable from each other it looks like my best bet is still a w57/58 or a r series box

MrDori · Post by **MrDori** » Tue May 08, 2007 9:29 pm

w boxe is cheap, maybe you can buy 4-5 w box untill you buy a r154.
The w57/58s have better ratios.

Try one behind it and see?

sxymr2 · Post by **sxymr2** » Tue May 08, 2007 11:01 pm

ouch broke the bellhousing and bent the input shaft but the box did not blow, its a w57 with a dog gearset inside

gmacrae · Post by **gmacrae** » Fri May 11, 2007 9:10 am

There is at least 1 rotory doing 9's on w5x gearboxes and hasn't popped it yet. My mate did plenty of 11.0 passes on a w55 in his v8 corolla.

How heavy is your car? Those boxes seem to take the punishment up to a certain kerb weight, then you'll pop them left right and centre. Though 500rwhp in anything is asking for trouble with a W box.

The r154 has a taller 5th gear than the w58 and esp w57, the other gears aren't much different. If you can get your hands on one, the r154 would probably be the way to go. Just replace the thrust washer with something tough (EN39B) and carburise it with the bearing retainer plate. Itll take all the power you can throw at it then.

KinLoud · Post by **KinLoud** » Fri May 11, 2007 9:48 am

Was the motor etc. solid mounted on the car that broke the bellhousing?
Bellhousing specially cast to adapt rotor to W gearbox?
Was there sign of fatigue cracking or was it a sudden catastrophic failure?

Ken
Ham
021 408 863

sxymr2 · Post by **sxymr2** » Fri May 11, 2007 5:15 pm

if you look closely at the pic you can see the adaptor still on the gearbox with whats left of the bellhousing still bolted to it.

not sure what make the bellhousing brake like that. was just doing a 3rd gear skid and it let go nothink over the top realy.

i use to do 5th gear skids in my old red 13b turbo powered early s1 rx7 all the time and all it cost me was tyres had allthe right gear to do it thow. but that car was only 200rwkw a good number for a street car

my new car however just overheats and brakes stuff with me just looking at it

http://homepages.ihug.co.nz/~derekrol/Untitled%20-%201.jpg

postfach · Post by **postfach** » Fri May 11, 2007 5:25 pm

where did you get the dog gearset?

overcast · Post by **overcast** » Fri May 11, 2007 6:17 pm

Toyota gearbox specs

http://users.tpg.com.au/users/loats/tec ... boxes.html