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Tremec TKX 5 speed vs. A-833 4 speed....

It’s hard to tell what’s going on here, but these are a couple of pics of the driver’s side of the trans, fully installed. The passenger side seemed to have better clearance than the driver’s side. No cutting necessary.

B4D76CDA-D205-468E-811F-E881F0C3C9D4.jpeg


DB53FDEC-44CC-4102-A8BC-79124A5BEA53.jpeg
 
It is a nice transmission and is much smaller than the older Tremecs, but for a B body Mopar, you still need to cut up your transmission tunnel to make it work. I spoke with a Tremec guy at Carlisle who confirmed this.

Yes, the Passon A-855 took me 5 years of waiting to get (prior to that I used a cast iron A-833 with OD gears and the shitty 3.09 1st gear). But, once I got it, it dropped in place using all my stock parts, with the shifter in the stock location. I love it - it works beautifully.
Yeah, I hate that tractor gear too
 
The only hole I had to cut was for the shifter. I had to remove a couple of screws from the rubber boot for the A-904 shifter rod for clearance, but I did not have to cut anything to clear the transmission housing.
I realize I used the wrong phrase by saying "cut up the transmission tunnel". As you stated, the shifter cannot be in the stock location so you need to cut a hole in the transmission tunnel for it. Obviously, on a manual car, the original shifter hole needs to be covered up as well.
 
I know there’s people that can’t afford to spend $7k plus on a tranny swap but then there is those that can’t afford it but can afford their bad habits and so forth. So I made my car my bad habit instead. I was one of the first ones on Jamie’s list for the 855 but after getting skipped over several times I said to hell with it and made the decision to put a Close Ratio T-56 Magnum in it. I didn’t care what cutting it took to get it in the car and after I drove it I’ve never been happier with my decision. With a gear ratio of 2.66, 1.78, 1.30, 1:1, .80, .63 it’s the best standard transmission I’ve ever driven.
 
It is a nice transmission and is much smaller than the older Tremecs, but for a B body Mopar, you still need to cut up your transmission tunnel to make it work. I spoke with a Tremec guy at Carlisle who confirmed this.

Yes, the Passon A-855 took me 5 years of waiting to get (prior to that I used a cast iron A-833 with OD gears and the shitty 3.09 1st gear). But, once I got it, it dropped in place using all my stock parts, with the shifter in the stock location. I love it - it works beautifully.
what did it end up costing if you dont mind me asking? Do you whale on your car every now and then? whats the rpm in 5th on highway?
 
I know there’s people that can’t afford to spend $7k plus on a tranny swap but then there is those that can’t afford it but can afford their bad habits and so forth. So I made my car my bad habit instead. I was one of the first ones on Jamie’s list for the 855 but after getting skipped over several times I said to hell with it and made the decision to put a Close Ratio T-56 Magnum in it. I didn’t care what cutting it took to get it in the car and after I drove it I’ve never been happier with my decision. With a gear ratio of 2.66, 1.78, 1.30, 1:1, .80, .63 it’s the best standard transmission I’ve ever driven.
price?how long on the wait and how much cutting on the floor? Used stock parts?
 
price?how long on the wait and how much cutting on the floor? Used stock parts?
I bought the T-56 in 17. I got it right away of course back then. I bought a complete kit that included a hydraulic clutch and everything. I paid $7k for it back then but the clutch they gave me was junk. I’ve since went to a McLeod that I haven’t installed it. We cut a pretty good little chunk out of the floor and made our own hump. Not perfect but it turned out pretty good back then.
 
what did it end up costing if you dont mind me asking? Do you whale on your car every now and then? whats the rpm in 5th on highway?
1 thing to be careful about installing a TreMac in a Mopar besides the transmission width is its length of the tailshaft.. Often this requires the engine to be pushed down slightly which tends to not allow an air grabber base to set flush with the hood scoop gasket..

Just my $0.02...
 
the pickup and van od a833 trans has a diff gear package . with more od gearing . but those od tranny's use weak teeth gears . i've broken them behind small blocks . okay to cruse with . here is a setup for an a body with a long rear stock . modified shifter mount for an a body . and my curd heavy duty shifter rods make more positive gear in n out .

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what did it end up costing if you dont mind me asking? Do you whale on your car every now and then? whats the rpm in 5th on highway?
I bought an 18 spline clutch as well since my other A-833 was a 23 spline. With a complete clutch and the tranny, plus a new transmission yoke that slips in to the transmission (mine was pretty shot), I was right around $6000.

But all stock parts are used. The stock bellhousing, stock driveshaft, shift linkage, etc. You can swap an A-855 for an 18 spline A-833 simply by swapping the transmission. That's it. There is no other work needed to install it. No holes to cut, no tunnels to modify, no driveshafts to shorten or lengthen. And I can swap back and forth between the A-855 and my numbers matching A-833 in about 3 hours.

"What is the RPM on the highway" is a subjective question so that's hard to answer. You RPM depends on your rear ratio and tires. The overdrive ratio of the A-855 is 0.70. I have a 3.55, so that means my 3.55 rear effectively runs like a 2.48 rear differential. So at 80 MPH on the highway, I am roughly 2700 RPM - I haven't checked it exactly.

Do I wail on it? Of course!!! That's what muscle cars are for! Right now I have my bone stock 383 engine (never been apart) in my 70. I had my 500 CI stroker with 620 HP in the car for a couple of months. The transmission handled it without complaint. I have since pulled the 500 stroker out just to check it and freshen it up. When the stroker was in, it simply tore the rear tires (275/60R15) lose at almost any speed, so I am not sure how hard I stressed the tranny though. IIRC, it is supposed to be able to handle around 700 lb ft of torque.
 
It's been mentioned a couple times that the shifter location is not stock with the TKX. TKX kit from Silver Sport retains the stock shifter location. Not sure that's true with the American powertrain kit.
 
Long thread here.

Was final answer to Silver Sport kit and be done with it?

:thumbsup:


watermelon
 
Depending on your willingness to do some fabrication a new TKX is $2800... I've seen a few of the QT Bellhousings... After spending time trying to align one of those I'd rather modify the stock piece myself... The crossmember should be pretty easy, I've built a few in the past
 
But when installing a Tremac TKX U need to change bell housing, clutch linkage... The Passon OD drop right in without any mods.. So in the long run the Passon OD is less expensive..

Just my $0.02...
You have to change all that if you go from a automatic to a manual. My passion that’s on order is going into an automatic car that I’ll have to do a lot more cutting to the trans tunnel not so if I went with a Tremec TKX.
 
If they ever go out of business would you be able to get parts?
I know, I’ve been waiting on a Passion for a while now, I’m 23, I probably won’t see it until I’m 30. Imagine waiting for a part. Where a Tremec TKX you can get the part within three days if needed.
 
The American Powertrain kit will put the stick in the stock location for the 4-speed shifter. You'll need to order the White Lightning shifter with a 2.25 inch offset (4-speed top plate on auto console)

Originally, I thought I would just cut up my very-pitted-and-rough-looking automatic top plate, but when I really looked at the job, I realized that was not a good idea. So I ended up buying an aftermarket 4-speed top plate. I had no issues installing the 4-speed top plate on the automatic console. I don't really care for the stick that came with my kit, so I'm exploring options. I'm going to try the classic, Hurst 4106 stick to see how that works.
 
The American Powertrain kit will put the stick in the stock location for the 4-speed shifter.
Will it do this for a real 4 speed car? I wasn't aware there was any Tremec transmission swap that allowed for a stock location of the shifter.

If there is, a link would be appreciated.
 
It is a nice transmission and is much smaller than the older Tremecs, but for a B body Mopar, you still need to cut up your transmission tunnel to make it work. I spoke with a Tremec guy at Carlisle who confirmed this.

Yes, the Passon A-855 took me 5 years of waiting to get (prior to that I used a cast iron A-833 with OD gears and the shitty 3.09 1st gear). But, once I got it, it dropped in place using all my stock parts, with the shifter in the stock location. I love it - it works beautifully.
5 years is a long wait. I guess I should get my order in now. Did you have to pay for it first and then wait 5 years, or do you pay for it when its ready?
 
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