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-   -   GeForce, Liberty, Freddy Brown Transmissions (https://www.rx7club.com/rotary-drag-racing-167/geforce-liberty-freddy-brown-transmissions-653849/)

AnthonyNYC 05-19-07 01:27 AM

GeForce, Liberty, Freddy Brown Transmissions
 
In a nutshell can anyone explain the difference between the trannies listed above. I know the Gforce is a shifted tranny, Freddy Brown are automatics. It looks like the Liberty is the most expensive of the three, gforce 2nd and FB the cheapest. Which one would be the best option for a street/drag car and which for a drag only car?

Thanks,

Anthony

NOEL MELASA 05-19-07 08:03 AM


Originally Posted by AnthonyNYC (Post 6956034)
In a nutshell can anyone explain the difference between the trannies listed above. I know the Gforce is a shifted tranny, Freddy Brown are automatics. It looks like the Liberty is the most expensive of the three, gforce 2nd and FB the cheapest. Which one would be the best option for a street/drag car and which for a drag only car?

Thanks,

Anthony

LIBERTY WILL BE THE BEST.

enzo250 05-19-07 08:16 AM

Anthony the automatic would be the only one you could drive on the street.

Gforce's, Liberty's, etc cannot be downshifted and are strictly drag race.

Both Gforce and Liberty are good transmissions, Although i prefer the liberty..

joe-c 05-19-07 08:38 AM

wat race transmissions can you downshift with?

crispeed 05-19-07 09:37 AM

Both Liberty and G-force make tranies that you can down shift. As long as the tranny is not of a full clutchless shift design and you use the right shifter then it can be downshifted.
I would say Liberty would be the clear winner because they have numerous designs and combinations to suit your needs.
Liberty just re-introduce their version of the famous 'Doughnash' design trannny that many people still use from back in the day.
You can also speak to Liberty about their gear setup for the inside of the stock Mazda tranny something I know 'Enzo' can comment on. :)

crispeed 05-19-07 09:45 AM


Originally Posted by NOEL MELASA (Post 6956339)
LIBERTY WILL BE THE BEST.

Now how did I know you would say that. :rlaugh:

NOEL MELASA 05-19-07 10:06 AM


Originally Posted by crispeed (Post 6956484)
Now how did I know you would say that. :rlaugh:

:lol: :lol: THANK YOU SIR:lol: :lol:

RXn407 05-19-07 04:43 PM

i heard that they can be found on e bay for like 1400, the doug nashs' n i heard theyre the bang for the buck, starting point.

AnthonyNYC 05-20-07 02:15 AM

Thanks for the responses.

Anthony

ErnieT 05-21-07 04:34 PM

Anthony,
I have had nothing but great results with my PPG tranny. I suppose some more testing is in order since I havn't cut a 1.50 60' with it yet, but so far its working great.

AnthonyNYC 05-22-07 01:46 AM


Originally Posted by ErnieT (Post 6963211)
Anthony,
I have had nothing but great results with my PPG tranny. I suppose some more testing is in order since I havn't cut a 1.50 60' with it yet, but so far its working great.

How streetable is that tranny? If you wanted to take an hour drive or so, can you or would it be too noisy or damage the tranny etc?

Anthony

ErnieT 05-22-07 06:16 AM


Originally Posted by AnthonyNYC (Post 6964938)
How streetable is that tranny? If you wanted to take an hour drive or so, can you or would it be too noisy or damage the tranny etc?

Anthony

If your in 5th gear its quiet as stock because its 1 to 1. The other gears wine because of no syncros, but you CAN get the tranny with syncros, its just not rated for as much power.

RICE RACING 05-22-07 06:40 AM


Originally Posted by ErnieT (Post 6965134)
If your in 5th gear its quiet as stock because its 1 to 1. The other gears wine because of no syncros, but you CAN get the tranny with syncros, its just not rated for as much power.

mate :)

dog engagment has nothing to do with gear noise ;)

this only happens due to gear tooth profile being flat and direct line contact on mating gears v's rolling point contact on semi helical or full helical oem box's :) :) :) therfore almost as much WHINING as a wife long after the honey moon has ended :)

crispeed 05-22-07 06:44 AM

Ernie.
It's not the syncros that make it wine. It's the straight cut gears that do. All transmissions with straight cut gears will exibit noise in the lower gears with 1:1 being the quietest.
The clunking and banging noise is due to the face plate dogs setup. Since there are no more syncros and there's a wide gap between the dogs often only six to eight vs the stock setup which might have three times the amount to smoothen the shift.

RICE RACING 05-22-07 06:47 AM


Originally Posted by ErnieT (Post 6965134)
If your in 5th gear its quiet as stock because its 1 to 1. The other gears wine because of no syncros, but you CAN get the tranny with syncros, its just not rated for as much power.

have you done a fluid change on your box yet? let us know how many fragments you find....... generaly dog box's *depending on skill of driver* will shed alot of bits and these are little pieces from your dogs *woof woof* they eventualy loose enough bits (usualy within 3k or less of road running) for the box to either shit a bearing (if not cleaned regularily enough to rid of contaminants) or it will jump out of gear as the dogs *woof woof* have lost too much material to stay engaged under load.

They can take quite a bit of abuse but i have seen dog boxes in everything from motorbikes, to trucks and they all suffer at the hands of an inexperienced operator. Even if you have a lot of sympathy they still have a hard time.

crispeed 05-22-07 07:11 AM

Proper driver shifting technique along with frequent oil changes are the key to making those trannies last especially on a street car. If you're serious about racing then you would have an extra set of face plates/dogs along with sliders that is if the design of the tranny allows you to change the face plates/dogs as an individual component or else it's going to get very expensive to have extra spare complete sets of gears with the dogs attached to them. Some companies weld the dogs to the stock gears while others are machined as part of the upgraded gear and offcourse the real pro trannies would have them as a seperate changeable component.

These pics show a compromise in design between a straight cut gear and a stock type gear. This design is a lot stronger than stock and will be a lot quiter than a straight cut design but not as strong. It's a nice option for a street type setup.

http://www.g-forcetransmissions.com/images/t5/lg_1.jpg
http://www.g-forcetransmissions.com/images/t5/lg_2.jpg

Another option for stock type gears.
Proshift dogs. Notice the welded on dogs.
http://www.libertysgears.com/Pro%20Shift%20Gear.jpg
Vs Stock gear.
http://www.libertysgears.com/Stock%20Gear.jpg

A gear set with face plate engagement. Notice the removable dogs on some of the gears.
http://www.libertysgears.com/Face%20...Gear%20Set.jpg

The daddy of all clutchless trannies in my opinion.

http://www.libertysgears.com/opentransgrey.jpg

RICE RACING 05-22-07 07:14 AM

My Quaife gearbox is a semi helical design with full *soft cock* syncro action for crusing duty when it comes time to pick up the local sluts :)

crispeed 05-22-07 07:18 AM


Originally Posted by RICE RACING (Post 6965211)
My Quaife gearbox is a semi helical design with full *soft cock* syncro action for crusing duty when it comes time to pick up the local sluts :)

*soft cock* :rlaugh:

crispeed 05-22-07 07:46 AM

A fully re-worked T-5 Transmission from G-Force.
I'm going to be testing one of these soon.

http://www.g-forcetransmissions.com/...5/inter_lg.jpg

Different options.
Syncronised kit with helical-cut gears
http://www.g-forcetransmissions.com/...CAL-CUT_lg.jpg

Helical-cut with dog rings.
http://www.g-forcetransmissions.com/...og-Ring_lg.jpg

Straight cut with dog rings.
http://www.g-forcetransmissions.com/...IGHTCUT_lg.jpg

RICE RACING 05-22-07 07:49 AM

The daddy box you post above I saw apart at a drag meet here (box out of MR12A) fastest 12A untubbed car in world 730+rwhp 12A and it had weld on gears on the two side shafts (not splined as in that photo), but otherwise ideantical construction with case that allowed it to be easily split in pits.

Long story short it was jumping out of 4th gear and the dogs *woof woof* were fucked on it after 80 passes or so.

Its a fucken BIG BOX ! and is massive in real life, stongest thing I ever seen in such a small car but the dogs *woof woof* still got jamed in the A hardcore ;)

I was spewing because i drove a long way to see it run and they said the box was jumping out of gear on the dyno when tuning it, anyway pulled it down at track and thats what i saw :) :) :)

crispeed 05-22-07 07:59 AM


Originally Posted by RICE RACING (Post 6965271)
The daddy box you post above I saw apart at a drag meet here (box out of MR12A) fastest 12A untubbed car in world 730+rwhp 12A and it had weld on gears on the two side shafts (not splined as in that photo), but otherwise ideantical construction with case that allowed it to be easily split in pits.

Long story short it was jumping out of 4th gear and the dogs *woof woof* were fucked on it after 80 passes or so.

Its a fucken BIG BOX ! and is massive in real life, stongest thing I ever seen in such a small car but the dogs *woof woof* still got jamed in the A hardcore ;)

I was spewing because i drove a long way to see it run and they said the box was jumping out of gear on the dyno when tuning it, anyway pulled it down at track and thats what i saw :) :) :)

The welded on set is an early design. The dyno does place a lot of stress on the dogs. I've seen brand new transmissions that are damaged after a tuning session on the dyno vs the same box lasting almost a 100 passes at the strip.
It comes down to driving technique most of the times. One fuck up and that brand new tranny is going to push out of gears due to damaged dogs and sliders.

RICE RACING 05-22-07 08:03 AM

I like the soft cock option :)

NOEL MELASA 05-22-07 08:04 AM


Originally Posted by crispeed (Post 6965206)
Proper driver shifting technique along with frequent oil changes are the key to making those trannies last especially on a street car. If you're serious about racing then you would have an extra set of face plates/dogs along with sliders that is if the design of the tranny allows you to change the face plates/dogs as an individual component or else it's going to get very expensive to have extra spare complete sets of gears with the dogs attached to them. Some companies weld the dogs to the stock gears while others are machined as part of the upgraded gear and offcourse the real pro trannies would have them as a seperate changeable component.

These pics show a compromise in design between a straight cut gear and a stock type gear. This design is a lot stronger than stock and will be a lot quiter than a straight cut design but not as strong. It's a nice option for a street type setup.

http://www.g-forcetransmissions.com/images/t5/lg_1.jpg
http://www.g-forcetransmissions.com/images/t5/lg_2.jpg

Another option for stock type gears.
Proshift dogs. Notice the welded on dogs.
http://www.libertysgears.com/Pro%20Shift%20Gear.jpg
Vs Stock gear.
http://www.libertysgears.com/Stock%20Gear.jpg

A gear set with face plate engagement. Notice the removable dogs on some of the gears.
http://www.libertysgears.com/Face%20...Gear%20Set.jpg

The daddy of all clutchless trannies in my opinion.

http://www.libertysgears.com/opentransgrey.jpg

***HEY CRIS I WANT ONE FOR THE STARLET***:lol:

crispeed 05-22-07 08:09 AM

You know the Tel.#! :rlaugh:

crispeed 05-22-07 08:39 AM


Originally Posted by RICE RACING (Post 6965297)
I like the soft cock option :)

What about those sluts you mentioned! :rlaugh:


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