New 5th gear for the R154 - how about a taller overdrive?

[alloyguitar]

Okay, you've peaked my interest. I'm looking at swapping in a 4.30lsd from my 3.73lsd and this was one of my principle concerns. I like it!

 

[CPT Furious]

My thinking also! Just ordered a 4.30 LSD from a board member for this mod!

 

[Doward]

Sounds like a plan!

Ok, I've got 6 sets for the first Buy-in. I'm contacting my cryo guy today, that will take a week or so (they work only on the weekends, and ship on Mondays - so if it's not done this weekend, it'll be next weekend).

Price will be $495/set - this includes the new 5th counter gear locking nut. I will ONLY have these 6 sets to start with. I am also going to offer transmission rebuilds - either basic rebuilds, or blueprinted rebuilds.

I've got access to 2 good R154 cores. The way it will work is like this:

If you want a rebuild, you will send me the parts you want in your transmission. I'll rebuild one of the transmissions I have here with your parts, and as soon as the rebuild is complete, I will contact you. At that point, I'll box the transmission up, and you can either:

a) send me your transmission (just the tranny - no bellhousing or hydraulics), then I send you your fresh transmission, or

b) pay a core charge that I will refund once I receive your transmission.

I have 2 cores, so I will do NO MORE than 2 at any one time.

Pricing will be simple - if you just want your 5th gear installed in your transmission - $250. If you want a basic rebuild, $500. If you want a blueprinted rebuild, $800. This does NOT include parts, but I'll install whatever you like into your transmission.

I'm just awaiting approval to make this all official, but figured you guys wanted to see where everything stood.

BTW, do NOT send your transmissions still filled with oil - it makes a mess. Always send the transmissions dry. I will be sending you guys 3 qts of oil with your transmissions

Naturally, you are free to buy the gears and pop them in yourself. It is actually pretty damn easy

 

[CPT Furious]

PM sent...

 

[Doward]

Alright! Accepting payments for the new improved 5th gear sets:

http://www.supramania.com/forums/showthread.php?t=98242

Also working on becoming a Misc. Vendor here on the site. I figure what the heck - I've been bringing parts to market for some time now, so why not?

Also - working with Driftmotion on putting together a discount price if you buy a full set of R154 parts from Aaron. You'll get a discount on buying the R154 rebuild kit, MC thrust washer, and MC bearing retainer all at once

Too bad Aaron doesn't have a shop here on the East Coast - I'd work with him in a hearbeat!

 

[Doward]

Posted some videos in the Misc Vendors thread

 

[tissimo]

wow, the drop in rpms is a lot more then I expected. It pretty much makes 5th useless except for cruising.

Time to get a antisurge cover if youre going to use this with a big turbo.

 

[Doward]

Remember, this is on 3.73s - so it's the absolute lowest ratio setup (or you might say, capable of the highest gas mileage)

How many of you guys on here are running turbos that surge at 4000 rpm?

4th gear on a 3.73 @ 7000rpm runs to just shy of 140mph.

Please raise your hand if you are trapping 140+ in the 1/4 mile. Except for really long highway pulls into the 150+ mph territory, you're not going to be running in 5th anyway

 

[teamslow]

What would be the top speed with the stock rev limter using the .66 gear with the 3.73lsd (I'm assuming the 3.73 is the standard on the turbo models, correct?)

 

[tissimo]

Remember, this is on 3.73s - so it's the absolute lowest ratio setup (or you might say, capable of the highest gas mileage)

Rpms will drop the same no matter what rear end ratio you're running

How many of you guys on here are running turbos that surge at 4000 rpm?

My old 67 on my 1j would surge a bit in 5th ~ 4000-4500

4th gear on a 3.73 @ 7000rpm runs to just shy of 140mph.

Please raise your hand if you are trapping 140+ in the 1/4 mile. Except for really long highway pulls into the 150+ mph territory, you're not going to be running in 5th anyway

I'm talking more of highway runs then anything.

But if you have a 3.91 or a 4.30 its much more likely you'll be shifting to 5th in a 1/4 mile run if youre making power.


Any info on gas mileage savings? I'm not entirely sure there'll be much increase. My old 87 w/ a 4.30 lsd got the same mileage as when i put 3.91s in it. Though it was mixed driving, so maybe highway is where it'd shine. (fwiw I got 19-20 mixed normally (50/50) and 21-22 with ~ 75% highway with both.)

 

[RedGT]

I got a 4.30 rear with a W58. When I can afford a R154 I am definately buying these gears!

 

[Doward]

Rpms will drop the same no matter what rear end ratio you're running

Wrong -

@ 40mph
3.73s will experience a 187 rpm drop vs stock R154
3.91s will experience a 197 rpm drop vs stock R154
4.30s will experience a 216 rpm drop vs stock R154

@ 80mph
3.73s will experience a 375 rpm drop vs stock R154
3.91s will experience a 393 rpm drop vs stock R154
4.30s will experience a 432 rpm drop vs stock R154

The lower the gears you're running in the rear, the more of a drop you will get VS THE STOCK R154, due to the way your final drive ratio is calculated (rear diff * 5th gear)

My old 67 on my 1j would surge a bit in 5th ~ 4000-4500

A 67mm turbo is more appropriately sized to a 3.0L motor than a 2.5L, you know that! BIG difference in 92 vs 71.5mm of stroke (aka the torque created)

I would NOT recommend this 5th gear to anyone with a 1JZ running smaller than 4.10 gearing in the rear differential. The torqueless 1JZ would be hell to drive, in my opinion.

I'm talking more of highway runs then anything.

This is true - and if ultimate acceleration in 5th is not your thing, this isn't your gear to use. Stick with stock.

If you'd like to be able to cruise all over the interstate without spinning 3000+ rpm, this gearing IS for you

But if you have a 3.91 or a 4.30 its much more likely you'll be shifting to 5th in a 1/4 mile run if youre making power.

A 3.73 can trap 7000rpm @ 139mph
A 3.91 can trap 7000rpm @ 132mph
a 4.30 can trap 7000rpm @ 120mph.

If you're running a 4.30 gear, your switch from 7000rpm in 4th, will land you @ 4632rpm.

I have to ask, who here is trapping 120+ with 4.30 gearing, and is even considering this 0.66 gear? This isn't for 1/4 mile racers, the gearing is for highway super-cruisers.

Any info on gas mileage savings? I'm not entirely sure there'll be much increase. My old 87 w/ a 4.30 lsd got the same mileage as when i put 3.91s in it. Though it was mixed driving, so maybe highway is where it'd shine. (fwiw I got 19-20 mixed normally (50/50) and 21-22 with ~ 75% highway with both.)

If anyone figures out a way to keep Jeff's foot out of WOT, we can tell LOL! All I can say so far, is that he gets about 200 miles to a tank WOT everywhere. In the next week or so, we should be taking a trip to Ocala for some detailing, so I hope to get a good highway MPG reading then.

 

[Doward]

First set sold - Thursday we should finally be able to get an actual highway mileage for the new gear!

 

[Doward]

Alright, we've got pricing for the parts to rebuild and strengthen your R154 to handle the abuse you want it to take

 

[burlguy]

Did the gear end up failing? Is it still handling abuse? My tranny is going out and this thread just seems to have died. I need one asap.

 

[CPT Furious]

After I get mine installed I'll tell ya!

 

[burlguy]

Is he still doing rebuilds with the upgrade? I have to get this thing repaired asap.... I have a road trip in early summer and that is fast approaching. I may have to go to the local tranny shop but I prefer not to.

I have sent him a pm and urgently await a response.

 

[turbo87targa]

im about to be swaping trannys and having one rebuilt....depending price i might want one

 

[Cz.]

I haven't seen Doward on in a while... Anyone know if he still has these available? I've was planning to get one once my car was done... but it's still not done.

 

[burlguy]

He hasnt been active in months. I wanted a tranny rebuild and still do.