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-   -   turboII trans to 12a? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/turboii-trans-12a-681312/)

ultimatejay 08-19-07 09:53 PM

turboII trans to 12a?
 
Ok, I've searched for the past two hours and I can't find any clear answers to this, so please help me out.

I want to install a turboII trans onto my 12a. The only two questions I have is what flywheel and clutch do I need and what starter to make this work and still retain proper engine rotating balance? I currently have the stock 12a flywheel with the 215mm disc.

Thanks,

Jarret

Kentetsu 08-20-07 07:26 AM

Get ahold of Man in Black. He has done this. There is also a modification needed for the shifter itself, if I recall correctly. He can get you the info on this as well...

Siraniko 08-20-07 08:21 AM


Originally Posted by ultimatejay (Post 7252226)
Ok, I've searched for the past two hours and I can't find any clear answers to this, so please help me out.

I want to install a turboII trans onto my 12a. The only two questions I have is what flywheel and clutch do I need and what starter to make this work and still retain proper engine rotating balance? I currently have the stock 12a flywheel with the 215mm disc.

Thanks,

Jarret


You need an old school bellhousing (pre-RX7) and use it on the TII tranny. But I still think its an overkill for a 12-A bridgeport. IMHO, a stock non-turbo tranny should do the job.

For the other question, is it going to be a daily driver or occassinoal track car as running an aluminum/lightened steel flywheels can be a pain sometime. A better idea is to grab the 81-82 stock flywheel (appx 21 lbs vs stock 27+) along with puck clutches (4 or 6) and a 3,000 lbs pressure plate. I know where to get them nice light stockflywheel. :)

steve84GS TII 08-20-07 07:09 PM

Easiest way to do it.......

TII trans
TII starter
TII light flywheel
12A rear counterweight that is correct for your engine
TII clutch

Not the cheapest route,but the simplest.Plus,adding a light flywheel is almost always a good mod.

boriqua51371 08-20-07 07:15 PM

i agree with steve thats the easiest way to go if you find the formentioned parts its the simpleste way or if not go the wacky way.

ultimatejay 08-20-07 11:57 PM


Originally Posted by steve84GS TII (Post 7255255)
Easiest way to do it.......

TII trans
TII starter
TII light flywheel
12A rear counterweight that is correct for your engine
TII clutch

Not the cheapest route,but the simplest.Plus,adding a light flywheel is almost always a good mod.


Thanks guys for all the info. Now the decision time......

Siraniko 08-21-07 12:27 AM


Originally Posted by steve84GS TII (Post 7255255)
Easiest way to do it.......

TII trans
TII starter
TII light flywheel
12A rear counterweight that is correct for your engine
TII clutch

Not the cheapest route,but the simplest.Plus,adding a light flywheel is almost always a good mod.


Either way, its not a very wise option IMHO.

steve84GS TII 08-21-07 10:49 PM

There is truth there.

While the TII trans is very tough,its also heavier and has taller gears.Not the best of things for a bridgeport,espeically if you have a serious porting AND go light on the flywheel.

Dropping the rearend ratio down will help offset the taller TII gears,some 4.44 or even a GSL-SE 4.07 gearset will help.........or run small wheels/tires.

ultimatejay 08-21-07 11:06 PM


Originally Posted by steve84GS TII (Post 7259252)
There is truth there.

While the TII trans is very tough,its also heavier and has taller gears.Not the best of things for a bridgeport,espeically if you have a serious porting AND go light on the flywheel.

Dropping the rearend ratio down will help offset the taller TII gears,some 4.44 or even a GSL-SE 4.07 gearset will help.........or run small wheels/tires.


Thanks, I plan on running 4.88 gears n/a and 4.44 or 4.11 for my turbo setup.

FBsliderseven 08-22-07 08:29 PM

just buy a TII motor...you'll love the power and it's easier to upgrade turbos.

Man_in_black49464 08-22-07 09:10 PM

The T2 tranny on a 121 is way over kill!!!!
The tranny that comes with the 12a is pritty tuff it can hold up to 350 hp without moding it at all.
Doing a T2 adds a bigger tranny and little gain.

Also it all depends on what you are doing with the car that decides the tranny and gears.

Drag go 4.11
Auto Cross Keep it stock.
Drift/Road Course FULL T2 SWAP!!

ultimatejay 08-22-07 11:45 PM


Originally Posted by Man_in_black49464 (Post 7262291)
The T2 tranny on a 121 is way over kill!!!!
The tranny that comes with the 12a is pritty tuff it can hold up to 350 hp without moding it at all.
Doing a T2 adds a bigger tranny and little gain.

Also it all depends on what you are doing with the car that decides the tranny and gears.

Drag go 4.11
Auto Cross Keep it stock.
Drift/Road Course FULL T2 SWAP!!

I am going to keep the 1st gen 5speed for the 12a and see how it holds up. The reason I was thinking of the turbo II trans. was because I am going to turbo the 12a and then in the future put a 13bt or 20bt so I thought since I have everything out I may as well put the tII trans in. Alot of you are downgrading the 12a like it can't make any power. I know of people getting over 600 hp out of 12a's. Well, I found a cheap way out to fix my 1st gen tranny so I am going to run it and later put the tII trans. in. Thanks for the help and replies I learned alot and what I need for the future.

Jarrett

rotaryB-2000 08-23-07 08:29 AM


Originally Posted by ultimatejay (Post 7252226)
Ok, I've searched for the past two hours and I can't find any clear answers to this, so please help me out.

I want to install a turboII trans onto my 12a. The only two questions I have is what flywheel and clutch do I need and what starter to make this work and still retain proper engine rotating balance? I currently have the stock 12a flywheel with the 215mm disc.

Thanks,

Jarret


Jarret
The first gen or (na) trannies are just fine..
i have run all year with a 1986 tranny in my drag car running 26x8.5 and a 175shot on a holley plate...

Besides 2nd gear sucks on the TII trannies.

My new combo is a 1979 tranny with a 88 main shaft.

ultimatejay 08-23-07 12:14 PM


Originally Posted by rotaryB-2000 (Post 7263472)
Jarret
The first gen or (na) trannies are just fine..
i have run all year with a 1986 tranny in my drag car running 26x8.5 and a 175shot on a holley plate...

Besides 2nd gear sucks on the TII trannies.

My new combo is a 1979 tranny with a 88 main shaft.

1986? I thought 85 was the last year of the 1st gens.

Siraniko 08-23-07 12:28 PM

With old school, we can run up to 1991 trannies. We can also run TII trannies but they are too heavy. FD trannies will allow you to mount the motor closer to the firewall but they dont last.


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