Aussie Dual Range gearboxes

This is what I've been thinking (check my ultimate ORS thread). The dual range moves all the ratios closer together though.
I'm sure there's a happy medium.
 
thunder039 said:
i didnt think you could run the dual range in the turbo's???
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Yeah you can! and it's a common "conversion". It really changes the dynamics of the vehicle offroad - for a good change!

stilson said:
You can run them, it's just a matter of durability with the extra power of the Turbo.
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Don't abuse it - "dry clutching" is out of the questions, as it should be for any subaru gearbox!

Rally said:
They definitely can hook up to a turbo. Just be nice to it. Dumping the clutch is a big no no
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+1. It makes a huge difference offroad, especially when it's geared up with the 1.6 low range (really a re-engineered L series 1.59:1 low range).

bobbotron said:
I've often thought it'd be cool to just have 6 gears, gear 1 would be something so low you could skip all together on the road.
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Maybe, it depends on the 1st gear ratio. Venom got away with a version 6 (?) STi gearbox with 4.44 diff ratio offroad for a while with the H6 in front of it. But steep hill climb that a 2L DR foz and L series DR would do with a little bit of work was tough going on the single range H6...

Go the dual range, go gentle on it and you'll love it and it'll look after you too.

Cheers

Bennie
 
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Nachaluva said:
Please explain??? :huh::shrug:
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DO NOT: Rev the engine to redline and drop the clutch in the dry, or wet on bitumen!
I would in a 6 speed single range STI box, but not a 5 speed and especially not a dual range box.
An L-Series box is fine though :iconwink: It allows the wheels to slip and isn't as harsh on the transmission as an AWD box...

Top Tip: Do not try this at home, work, the streets or anywhere onroad you desire unless you have money to burn for a new gearbox when you blowup the diff and/or gearset.

Regards
Taza
 
this maybe a stupid question but can´t the dual range box be strenghened to hold up? or is it THAT different to the gears in a normal turbo 5spd?

my current gearbox is doing fine even when driven hard, i just avoid "jumps" or driving fast over bumps where the car looses traction since the subaru boxes don´t like that :) (except STI)

I have a cusco rear lsd 2way in my rear diff and that helps alot offroad too ;)
 
Nachaluva said:
Please explain??? :huh::shrug:
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I probably used the wrong name at the time, but I was meaning something like redline clutch dumps where you basically rev the tits off the engine and dump the clutch from a stand still.

Dry clutching is high rev gear changes without using the clutch, it's super hard on helical gears and should only be used on straight cut gears in racing applications. You can kiss your gearbox good bye very quickly if you do this!

Taza, I wouldn't say it's alright to do the clutch dumping on an L series even though it's front wheel drive, you're still stress loading a small part of the gear cogs, once one or two of these are weak enough there goes that gear and potentially the gearbox.

yallahyimshi: The dual range gearbox will be fine if you look after it. But if you're drag racing aggressively off from the lights all the time or "dropping the clutch" in low range than the low range won't last long. The rest of the gearbox in high range should be fine if you don't treat it harshly. You can still have fun with it - Dulagurl's dual range gearbox is going well - and he's got a H6 that delivers the berries lower down and more aggressively than a stock turbo would.

Cheers

Bennie
 
A mate of mine has a modified H6 Liberty with 6 speed gearbox. I'd love to see what is quicker- his Lib or my WRX. My money is on the WRX but who knows. Turbos are big on torque- more so than a 3.0 litre H6 and maybe even the 3.6 H6. As has been said already, driving style will mean a lot.
 
El_Freddo said:
Maybe, it depends on the 1st gear ratio. Venom got away with a version 6 (?) STi gearbox with 4.44 diff ratio offroad for a while with the H6 in front of it. But steep hill climb that a 2L DR foz and L series DR would do with a little bit of work was tough going on the single range H6...

Go the dual range, go gentle on it and you'll love it and it'll look after you too.

Cheers

Bennie
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It's kind of a moot point for us North Americans, it'd be a ton of money to either go to a dual range gear box or get some custom gearing.

Given the current gearing of my forester, I think one gear smaller would work. 1st is just a bit too fast, I think a gear lower would make slow speed maneuvers a lot easier.
 
bobbotron said:
It's kind of a moot point for us North Americans, it'd be a ton of money to either go to a dual range gear box or get some custom gearing.
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Fair enough, but why bring it up? I was helping to answer the OP's question about a dual range gearbox behind his EJ turbo in the XT...

bobbotron said:
Given the current gearing of my forester, I think one gear smaller would work. 1st is just a bit too fast, I think a gear lower would make slow speed maneuvers a lot easier.
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This is basically what the low range does - in the L series (1.59:1) low 2nd is just shorter than high 1st and so on...

If you're really keen to achieve something, you'll find a way to do it, even if that includes saving for two years to do it. No need to get bitter about the US not getting the dual range gearbox, we too have missed out on some awesome parts/models that you got over there!

Cheers

Bennie
 
El_Freddo said:
This is basically what the low range does - in the L series (1.59:1) low 2nd is just shorter than high 1st and so on...
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I may be wrong but in my SF Foz, it feels like the gearing goes 1st low; 1st high; 2nd L; 2nd H; etc. The better low range of the L-series will make a difference ;)
 
waiting for the final answer i guess i´ll get myself one of these gearboxes, and yes i have to save some money for that ;)

shipping will be pain as will be taxes/import fees... not to mention the cost of the tranny itself :rotfl:
 
thunder039 said:
i agree with the 1st low then 1st high then 2nd etc
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I have to disagree here. My 2nd gear low range is slightly lower than my 1st gear high. Then 3rd low is just higher then 1st. I find 5th low is similar to 3rd high.
Good inbetween gears which make most situations doable. A lower low 1st would be nice for taking off in rocky, rutty, hilly conditions but the rest of the gears are good.
 
Easiest way to find out is to do 2000RPM in each gear and record your speed.
 
Gidday Taza

taza said:
I have done this and that's how I worked it out. Can't remember what it was though.. will have to check it out tomorrow. I think I was doing about 4000rpm.
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The easiest way to do it is to multiply out the gear ratio and LR reduction ratio.

This will show exactly where the ratios lie in relation to each other.

If it stays cloudy, I will do this after I have had breakfast. Otherwise I will be driving my telescope watching the transit of Venus ...
 
HR & LR overall gear ratios for SF & SG Foresters

Gidday Folks

Here are the figures (unless I have stuffed the calculations up ... :iconwink: )

SF:

1st = 3.545 LR = 5.1296:1
2nd = 2.111 LR = 3.0546:1
3rd = 1.448 LR = 2.0953:1
4th = 1.088 LR = 1.5743:1
5th = 0.871 LR = 1.2603:1

FD = 4.111:1

LR = 1.447:1

SG:

1st = 3.454 LR = 4.1310:1
2nd = 2.062 LR = 2.4662:1
3rd = 1.448 LR = 1.7318:1
4th = 1.088 LR = 1.3012:1
5th = 0.780 LR = 0.9329:1

FD = 4.111:1

LR = 1.196:1

Of course, the SF and SG ratios are not directly comparable, even though they have the same FD ratio. The rolling circumference of the tyres is different, giving a different overall ratio. I will compute this difference later.

[EDIT]
Just checked. The rolling circumference of 205x70 15 is 2098.59 mm (476.51 revs/Km); 215x60 16 is 2087.28 mm (479.09 revs/Km); so almost identical.
This makes the above figures almost directly comparable between the SF and SG Foxes.
[end edit]
 
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question...Is there a d/r 4eat..with 4:44's ?

I 'm curious what you have available down under...
a d/r auto awd trans. w/ 4:44's..?

As I want a d/r for.. my foz....

Also will an h6 be equivealant with a 4eat auto 4:44 to a D/r 5mt getting about the nasty stuff..like crawling..? low end Torque vs gearing...

Just throwing out ideas..for my project..foz..

much thx..:biggrin:
 
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