Max horsepower through an R154?

**RabidChild** · 01-15-2004 03:00 PM

Hello,
I'm considering swapping in an R154 in place of my W58. . .does anyone know how much horsepower can be run on an R154? When they break, what usually goes? Any other problems with this transmission?

Thanks!
Beau Jepson

**Thermactor** · 01-15-2004 03:07 PM

its a tough trans, it's thrown down more than 700hp before. don't be stupid with it, though, or it will break the thrust washer. and the 2nd gear synchro likes to say "aight peace", too, so watch out for that.

**Trent** · 01-15-2004 03:07 PM

I've rarely ever heard of the R154 breaking because of power. Most of the time it's due to age or wear or harsh driving. Everyone that is running anywhere from 400rhwp to over 700rwhp is still on the R154, so it's pretty darn good.

**turbotoy** · 01-15-2004 03:22 PM

While I don't have an answer for you, the power is somewhat meaningless, it's the maximum torque you want to look at.

**Bugwugger** · 01-15-2004 04:24 PM

what is the difference between the 2, and how can u tell the difference?

**Ckanderson** · 01-15-2004 04:56 PM

The part that seems to brake, is the thrust washer between second and third. if you power shift between those two gears, youl mulch that washer, provided you have enough power....uhhh torque i mean...

**Wreckless** · 01-15-2004 05:32 PM

If you run an unsprung hub and dump the clutch, especially with high power and sticky tires, the 1st gear thrust washer likes to say "aight peace" too.
Keep good gear oil (Redline MT-90) in it and dont be harsh on the shifting/launches and it will hold up well.

**drjonez** · 01-15-2004 05:39 PM

Originally posted by turbotoy
While I don't have an answer for you, the power is somewhat meaningless, it's the maximum torque you want to look at.

afterall, HP is nothing more than tq @ a given RPM.....

**Simba** · 01-15-2004 06:02 PM

If you shift properly and don't abuse it, it'll take upwards of 800 pounds of torque before anything turns into gravel.

Of course, this assumes street tires on the street or a road course, and not slicks or drag radials on a strip. Drag racing will break things a hell of a lot faster.

Your mileage will vary, of course. A transmission with proper maintenance and an owner who knows how to drive will last a hell of a lot longer than one driven by a teenager.

**SoupedUpSupra** · 01-15-2004 06:07 PM

someone with the access needs to get the ball rolling on a better thrust washer.

**turbotoy** · 01-15-2004 06:28 PM

Give me a new one or the part number for the offending washer and I'd be glad to do the engineering and manufacturing.

**blackout_89t** · 01-15-2004 06:48 PM

Originally posted by Simba
If you shift properly and don't abuse it, it'll take upwards of 800 pounds of torque before anything turns into gravel.

Of course, this assumes street tires on the street or a road course, and not slicks or drag radials on a strip. Drag racing will break things a hell of a lot faster.

Your mileage will vary, of course. A transmission with proper maintenance and an owner who knows how to drive will last a hell of a lot longer than one driven by a teenager.

I resent that teenager remark :P I know how to drive.

**drjonez** · 01-15-2004 06:50 PM

heh. a decidedly teenage answer.....the truth is:

no you don't.

**chevyeater-on-sf** · 01-15-2004 06:53 PM

The thrust washer on the output shaft, in between 1st gear and the center support bearing is the one that appears to be the problem.

I am beginning to think that it may be due to the ball bearing design that Toyota used. Other high torque helical gear boxes I have seen use tapered roller bearings with some preload to avoid excessive fore/aft movement of the gear clusters. A better thrust washer would need to be more impact resistant.

**drjonez** · 01-15-2004 06:54 PM

Originally posted by turbotoy
Give me a new one or the part number for the offending washer and I'd be glad to do the engineering and manufacturing.

awesome. i'll help out if need be...

here's the exploded view of the trans:

http://www.cygnusx1.net/supra/librar.../mt/MT_50.html

2 thrust washers, which is the culprit?

**drjonez** · 01-15-2004 06:55 PM

heh. chev beat me to it!

**turbotoy** · 01-15-2004 07:21 PM

Cool, next time I make an OEM parts order I'll grab one.

**wastegate** · 01-15-2004 07:35 PM

No matter how much information I give to the forums and to the Supra community no one searches for it. ALOT of answers can be found this way. I have posted about this little shit of a spacer before. It's the 1st gear thrust washer. Sits between the main bearing and the 1st gear hub cluster.

http://www.turbosupras.com/pages/technical/R154.htm

**turbotoy** · 01-15-2004 07:50 PM

If someone could mic the shaft the washer fits on, that would be great too. Need +/- 0.0001" accuracy.

**drjonez** · 01-15-2004 08:19 PM

Originally posted by wastegate
No matter how much information I give to the forums and to the Supra community no one searches for it. ALOT of answers can be found this way. I have posted about this little shit of a spacer before. It's the 1st gear thrust washer. Sits between the main bearing and the 1st gear hub cluster.

http://www.turbosupras.com/pages/technical/R154.htm

you time would be better spent putting info somewhere useful:

www.mkiiitech.com

no matter how hard you try, people won't search here....

**wastegate** · 01-15-2004 09:20 PM

you time would be better spent putting info somewhere useful:

Time is a gift. Be thankful for it. I like to have as much time as possible. Unfortanlty that means most forums don't get visited. Tell you the truth I visit alot of forums less and less now due to dickheads.

Here is a list of threads on this forum alone that has information about this part.
http://www.supraforums.com/forum/sho...=thrust+washer
http://www.supraforums.com/forum/sho...=thrust+washer
http://www.supraforums.com/forum/sho...=thrust+washer
http://www.supraforums.com/forum/sho...=thrust+washer

No Bullshit Racing.

**SupraTrey** · 01-15-2004 09:35 PM

Originally posted by Trent@MVP
I've rarely ever heard of the R154 breaking because of power. Most of the time it's due to age or wear or harsh driving. Everyone that is running anywhere from 400rhwp to over 700rwhp is still on the R154, so it's pretty darn good.

HP doesnt Kill Trannys.... TQ does....... We will see soon how much she can hold

Trey

**spuTniq** · 12-17-2010 01:15 AM

what item do i need to replace to make the r154 stronger, i know trust washer..what about synchro gear..problem is..my third gear pop..when i try to engage it...i just got the r154 overhauled..using its repair kit..it broke on my 10th runs on the drag strip, using semi-slick,

engine is 7mgte, a/r 70 turbo, water cooled, managed with hks pfc, and hks aic, twin plate os-giken with r154 box, one piece long shaft, supra standard lsd.

**Bmettie** · 12-17-2010 04:54 AM

HOLY 7 YEAR THREAD REVIVAL
Try the search function
http://www.supraforums.com/forum/sea...hreadid=163252

**2JZA70Claou** · 12-17-2010 07:06 AM

I run a GT72mm turbo on my 2jz mk3 supra for 2 years now and everything is OK.
My R154 trans is the original trans that came with my 90' turbo MA70 supra.
We are talking about a 21 year old transmission/gear box. I might be boosting
around 500 rwhp. But next week I'll raise the boost to 26 psi and around 650 whp.
I don't drag race my car on a 1/4 mile drag strip though... I only abuse it on the streets!

R154 = Best Toyota transmission for High HP cars,no doubt.

*The V161 getrag (mk4 supra turbo box), is not better built or has more high
tech in it. It just has better/stronger metalurgy in some of it's 'moving' parts,
and it is a 6 speed trans. That's why it costs more than the standard R154...

*The W58 is a much smoother/friendly trans than the R154. But it can't handle more than 400 rwhp.
The R series trans is a heavy duty gear box oriented for high HP applications.
Treated with the right manners and care it can handle around 900 rwhp.

Thread: Max horsepower through an R154?

Thread Tools

Display

Max horsepower through an R154?

Posting Permissions