Gearbox Solutions

[Alf]

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I think the first gear is 3.5xx:1 and very similar between the two boxes

Taken from meggala's site http://www.meggala.com/r33transmission.html

R33 GTST

1st 3.214:1

2nd 1.925:1

3rd 1.302:1

4th 1:1

5th 0.752:1

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Supra 6 speed

1st - 3.827:1

2nd - 2.360:1

3rd - 1.685:1

4th - 1.312:1

5th - 1.00:1

6th - 0.793:1

TKO 500 TCET 4616 http://www.malwoodauto.com.au/TKO.htm

1st 3.27:1

2nd 1.97:1

3rd 1.34:1

4th :1:1

5th 0.68:1

* with this box i could use a taller diff ratio

To put things into perspective,Compare an rb30E 5 spd (suited for 3.45 diff)- mines a 3 litre bottom end.

1st 3.321:1

2nd 1.901:1

3rd 1.308:1

4th 1:1

5th 0.759:1

Yes your not wrong there the T56 is a heavier box but its strength is much greater (its used in dodge vipers corvettes etc..)

The only problem I can see is first gear, but in a 600hp RB30DET would it have enough torque down low to move it just as quick as first gear in a 25 box?

[Cubes]

Now that I'm running the RB30DET I would actually like a higher ratio first gear.

Some where inbetween first and second, maybe instead of 55km's in first say 65-70km/h.

A 4.11:1 diff ratio would probably make a nice improvement.

I should track down a Sim Drag program where you enter the engine specs in to Desktop Dyno or similiar which then copys the output over to the drag program, you enter all the gear ratio's etc and it gives a simulated 1/4 run.

[discopotato03]

I think you may find trying to launch an R33 with a 2.66 first and 4.111 final drive less than amusing . I worked on a few different diff ratios and about 4.875 gets a near acceptable ratio spread , and even then sixth is still moonshot gearing . IMO a big heavy poorly shifting truck box is not well suited to a performance car .

Surely there must be aftermarket gear sets available to fit a box that goes bolt and my guess is GTR bits (aftermarket) probably fit . If you and your wallet are serious about trackwork only a dog box will do .

Mines going to wear an RB71 box as I prefer less weight plus I'm kind to gearboxes and clutches , I don't drag race either . I would like to know the part no's of the RB71 (GTST) baulk rings (are 1st - 4th all the same ?) and the details of the bearing kit , though I think its only the lay shaft front bearing that is different to the earlier 71 series .

Cheers Adrian .

[Alf]

 

Surely there must be aftermarket gear sets available to fit a box that goes bolt and my guess is GTR bits (aftermarket) probably fit . If you and your wallet are serious about trackwork only a dog box will do .  

Mention skyline and the price is doubled, I'd rather buy a Tremec over a GTR box any day.

A dog box on the street is not practical.

[discopotato03]

No offence but how do you you plan to get 600whp to the tarmac through street legal tyres ?

The only thing that prevents me driving a dog box on the road is money . I figure if I can drive an 18spd Road Ranger dog box on the street (and I can) a small light box would be a piece of cake . Sure they clunk a bit due to the backlash but if they're designed right they go snick snick snick . Its up to the loose nut behind the wheel to get the revs and co ordination right .

[Alf]

No offence but how do you you plan to get 600whp to the tarmac through street legal tyres ?

it's 600hp @ the fly.

On the street be very subtle with the throttle.

On the strip, slicks with the widest combination possible.

yes I know it will have plenty of wheel spin, thats the plan :flamed:

[discopotato03]

Fair enough , I gave up on wheel spin a long time ago . I found it got me nowhere .

[Cubes]

Decent tyres hold 450-500hp without too many drama's behind an RB25DET.

Being the 3ltr it should be quite a bit more linear and controllable over the 25.

[someonestolecc]

Newb question - what's a dog box?

[Alf]

If you and your wallet are serious about trackwork only a dog box will do

You have got me thinking about the dog box.

Anyone got one here?

What price range are these in?

Besides holinger anyone else make them?

[Cubes]

Munro has been through a few.

[Bl4cK32]

os gearset is good (4-4.5k?)...you can choose long or short ratio too ...then dog / or trust(10kish), then hollinger(20k?)

[Alf]

os gearset is good (4-4.5k?)

Does anyone have any information on these?, specs, suppliers etc..

[abflug]

i got HKS dog box in my GTR its not to bad on the street but you need to think about what you are doing with the rpm. HKS boxes were made by Hollinger up till the late 90"s.

[Sydneykid]

Pfitzner make one too, costs around $7K. If I remember rightly Theo uses one of theirs as well. If I ever break the RB25DET gearbox I will be sending it down to them.