How much power can an r154 handle

[Pishk]

I read in a magazine doing a gearbox review, the R154 gearbox is rated at 550hp. This would be flywheel horsepower.

So that kind of answer's your question. However, if you abuse your box and have less power, it will still die after time. Also if you have more power and you treat it like a baby it may never break. Rated at 550hp, but depending on driving style as to how long it will last

[Norbie]

How was it "rated" at 550hp? The most powerful engine it fitted to (by Toyota) has 280hp.

[Gibbon]

What sort of cost would I be looking at for the labour part of the work to replace the bearing?

Thanks

I got a case hardened one made for $80....its fine, Dont try and pull the box apart urself unless you are very very observant and patient...
blake

[Pishk]

How was it "rated" at 550hp? The most powerful engine it fitted to (by Toyota) has 280hp.

Yeah umm, aren't we talking about a gearbox not an engine? so what that has to do with it I don't know. All i said was that's what a magazine printed. Now we all know that magazines dont print 100% correct info 100% of the time. I'm telling you the details so the guy who asked the question can take from it what he wants. Otherwise instead of listing the source I would have just said they are rated at that outright.

[Norbie]

Yeah umm, aren't we talking about a gearbox not an engine? so what that has to do with it I don't know.

Pretty obvious I would have thought? The more powerful the engine, the quicker the gearbox breaks.

I was making the point that Mr Toyota seems to think they're good to 280hp, and for more powerful engines like the 2JZ-GTE they decided the R154 wasn't up to scratch and stepped up to the Getrag V160. I haven't seen any credible evidence the R154 is rated at anything like 550hp. And no, a magazine doesn't come close to credible.

[hemi twofifteen turbo]

not necessarily the more power the engine the less life the box has. more like the more torque the engine has, the less life the box has. ie, 550hp @ 6000rpm out of a chev 454 vs 550hp @ 12,000rpm from a say a 6 cylinder screamer, all else being equal it's definatly the chev that's going to munch the box first.

[5000gt]

if i remember correctly, the r154 was either rated at 450, or 490 ft/lb torque..... found this out while researching gearboxes for a possible FI 1uz setup. The v160/1 was rated at 550 ft/lb i think.

End of the day, i'm going with an american box. Stronger than all the toyota and getrag boxes (600ft/lb) and comes with choice of .82 or .64 5th gear (im using the .64 version). V12 cruising at 1200 rpm FTW.

[Norbie]

American... 600ft/lb... TKO600?

[5000gt]

may have changed my mind since that last post.

My tko600 may be up for sale soon..... as im about to buy a t-56 (ex LS1) with double overdrive 5th and 6th gears which would suit my application better..... also, it's gonna be frikkin cheap thanks to JP (supraforums).

The difference after the sale of the tko will go to a new gearset for the t-56 once it blows, though i don't see that happening for awhile as they're mighty strong too.... nearly on par with the getrag (different versions supported 450-550 ft/lb torque).... plus there is heaps of support (american part).

Anyone want to work out my cruising revs??? haha
6th gear .5, diff ratio 3.2... wheel size 345/35/19....

[GriZZly]

approx 1282 @ 68mph/109kmh

or at 3000rpm ~ 159mph/256kmh

[5000gt]

haha, thanks for that, i was just making a point..... v12 + super low cruising RPM FTW!!!!!

[Norbie]

Top speed at 8000rpm = 747.48 km/h.

Methinks that gearing is completely inappropriate. Perhaps a NA diff ratio would suit the T56 better?

[RONA]

LS1's struggle to pull in 6th or theydon't at all, top speed is reached in 5th at about 275-280kmph at 6500rpm.

That puts it at 344kmph in fifth assuming 280kmph top speed at 6500rpm in fifth. And thats on the GTS using the 3.91 diff ratio. Not sure on the supra's diff ratio.

[JustCallMeOrlando]

The question I raise is what do the Tremec boxes shift like? I know the T56 shifts like ass. Is the TKO any better? Is the Getrag any better for that matter?

[5000gt]

the tko shifts nicest out of the 3..... the t56 is similar to the truck shifting r154.... the getrag is less clunky.... the tko shifts easiest.....

mind you, this is by just shifting the box on the stand... have yet to hook up the t56 or tko to feel it behind an engine, but i don't think it would change the standings....

JustenGT8 can also confirm as he has a tko in his celica.

As for diff ratio's, i have the option of 3.2, 3.7 and 4.1.... all of which can be had with LSD's of some sort or another. Also, i'd probably only use 6th for highway cruising.... sounds like a waste, but i don't see myself racing through all 6 gears in regular use anyways.....