a friend of mine plans to swap a 20B into an fc.. but he's having trouble on picking a tranny.. does anyone knoe of any tranny options that can withstand quarter mile driving?

 

Depends on what his HP expectations are. Also depends on his budget. Stock TII tranny should hold up under the stock twins. I would think. Any other turbo setup and I would look for another tranny. Has anyone ever tried cryo treating the stock gears? If so do they hold up well? Also shot peening?

-Destin

 

Just a few I've picked up:

dogmission
T5
powerglide (you did say quarter mile, right?)
Or how about the stock S4 or S5 T2 tranny?

Of couse anything could be used. It depends on the engine's power level and driver's skill.
Evil Aviator will need lots more info such as your budget etc to give you an informed answer.

 

yea, maybe somehow beefing up the stock internals. FD tranny internals are almost identical to Kouki turbo trans i think. Also gonna need a real strong input shaft, as Dragon has shown us that you can break even titanium input shafts. Im not sure if he was launching hard launches constantly or if this broke over time. maybe he can shed some light on it. i too am interested in somehow making the stock tranny work. there has to be a way....

 

^ Doesn't drag race.

 

^ Doesn't drag race. me?

 

LS1 tranny?

 

Yes, and doesn't drag race anybody else. I have never drag raced in my entire life. I may try it some day, but it just doesn't seem like something I would enjoy.

 

OH, i see....i thought you were talking about me...ehehehe. maybe cryo treating the gears like sillbeer said. I dunno...I know hks dogmission is easy fix, but really expensive and parts are *cough* a little short on this side of the ocean. I guess just dont hard launch it

 

So I take it no one has a final thought on the tranny options?

 

Guru dogbox. They make drag or circuit gear sets. You could get both. Uses the stock case. $5000+
Quaife (spelling) makes a 6 speed dog ring conversion that uses the stock case with minor modification. $10,000+
Jericho makes indestructable dog boxes with unlimited gear set options. 4 or 5 speed.
4-speed w/ internal shift linkage. $4000+
5-speed w/ external shift rails would require tranny clocked at slight angle for shifter to come through trans tunnel and the tunnel would still need some modifications. $5000+
These are what I looked into.
I will most likely be using the Guru setup when rthe time comes.

G-Force makes nice drag trannies.
Hewland and so on.
You could get any of them to work with enough mulla.

What is your budget?

 

well, yea those are all options. no one said 20b's are cheap....hehehe..a used hks 5spd dogmisison is around 4-5K depending on mileage. are the guru boxes rebuildable? I dont know too much about them, but I know that my T2 tranny will not last long. im hoping it will last a year, but I doubt it.

 

If you have $7.5K, HKS makes a box for the FC which'll hold 500ft.lbs and uses a standard synchro H pattern gearset (six speed). Ratios aren't the greatest for a three rotor (a bit low) but it does have an overdrive 6th and a 1:1 5th. It's a bolt in, features a stronger casing and gearset.

 

if you got the money to make this then good luck in coming up with the boat load of money for such a young person

 

Jap Village has a sequential (hope i spelled that right) six speed transmission that can withstand up to 420hp. it cost around $4700 without including shipping and they have it into a 20b FD

 

It should be rated for torque, not hp, as that's the measurement which matters most. There isn't a true sequential box out there that'll bolt into an FD for that amount of money. The Hewland box is about triple that ready to go.

 

i agree with tt95, it shouldnt be rated for HP as much as it should be for torque. hell, a stock S5 T2 tranny should hold that much...and 4700 sounds like alot for only 420"HP"

 

Anyone know how strong the Supra tranny's are?

 

I asked the same question to my Japanese buddy. I'm assuming you mean the getrag 6 speed. He said the gearing is way different and wouldn't work right. He told me what the gearing was and how it would affect driving the car but I don't remember the scenario he gave me.

-Destin

 

They are fairly strong and would handle a 20B. But check the ratios. Another option would be a 350Z tranny which is actually lighter than the FD's tranny.

 

Probably a dumb question and people here have probably already researched this. But what is the correct gearing for a 20b since we don't have a stock manual tranny to compare to? Are the transmissions discussed in this thread the only or most viable options?

 

Honestly, it really depends on a number of things such as form of aspiration (natural or turbo), power output and how the car will be used. Because a 20B generally has a wider torque curve than a 13B, gearing isnt as crucial. The fatter torque curve will allow the car to overcome slight miscues in gearing selection. Just a hypothetical, if you are running a 600hp+ 20B, overall short gearing may not be in your best interest! But its a combination of transmission ratios and the rear end ratio. What it boils down to is you will have to sit down and do a bit of math to figure out what is best for your application. Dont forget to take into account wheel size as well. Once that is figured out, take a look at the available off the shelf (so to speak) items and decide which one has the fewest compromises in gearing. Unless of course, you are willing to pay for custom gears! There are many other options out there as well from companies like GForce, etc...

 

One other option I keep forgetting about would be the Richmond 6-speed overdrive tranny.

http://www.jegs.com/cgi-bin/ncommerc...43&prmenbr=361

I don't know too much about it other than it handles well over 400ft.lbs. of torque and it's ratios are decent for a three rotor w/turbo.