Transmission opinions for a 2004 Mach 1 turbo

[sutyak]

I'd like some opinions regarding my next transmission for the Mach 1. The issue is the guy who owned it before me built the motor, rear end, added a big single turbo, but did nothing for the stock TR3650 except a stronger clutch. If I want any track time at all with this car I have to upgrade this transmission! Ultimately I don't know what I want to do with the car, but it will have at least 650 ft-lb torque to the the wheels. Here are the options as I see them. I'm looking for pros/cons of each.

Modified TR3650
Pros: All wiring etc. already there. Weight. Can be built to hold 1000whp.
Cons: Rare. Close to the cost of a T-56.

T-56 (Magnum?)
Pros: Strength
Cons: Cost. Availability. Need new driveshaft. Any wiring changes?

Automatic (modified 4R70W?)
Pros: Strength, longevity, and consistency. Faster 1/4 mile?
Cons: Cost. Complexity of installation. Auto vs. manual valvebody?

For the valvebody, does a manual mean full time manual shifting? Does this also mean I wouldn't need an ECU at all to control the shifting? If I wanted it to shift automatically, I would need a whole new ECU, correct? Then I would need to modify the tune to control the shifting?

I have the opportunity to buy a modified TR3650 for $500, but it sounds like it might need a syncro. It's supposedly built for 700 ft-lb of torque. That seems like a good deal if it doesn't cost much to fix it.

All opinions welcome. Ultimately what I want is a reliably strong transmission that I can take to the track and beat on, and not hate driving on the street the rest of the time.

[Mark Aubele]

I would spend the money once and just get a T56, mostly because of a usable 1st and 5th gear and it is a proven box (and easy to sell should you ever choose to go auto). The car will be faster with an auto, but you may have an issue facing your family and friends afterwards. :)

[sutyak]

Something else I just considered with something other than a TR3650 is having to rework the exhaust pipes to the turbo. Already there is a crossover pipe that basically touches the transmission.

[SlowSix]

Pics of the crossover ?
Is it a custom kit ?

I'd go t56 personally. Auto vs manual is up to personal preference really. Auto will be faster on the drag strip with a car that makes that kind of power.

[turbo83coupe]

Maybe if u get the one for $500, send it over to Wick if he is still messing with them. I know he has fixed several for me and some others. Does good work. I just saw him post in the carb rebuild thread...

[George C]

Th400 and call it a day


Turbo and t56 makes as much sense as obama in office

[sutyak]

Pics of the crossover ?
Is it a custom kit ?

I'd go t56 personally. Auto vs manual is up to personal preference really. Auto will be faster on the drag strip with a car that makes that kind of power.

It's a Hellion single turbo kit. If I would have made the setup it would use forward-facing manifolds like George's truck. For now I'll stick with the current turbo setup.

Here is the driver-to-passenger side crossover where the tubes merge for the single turbo.

[sutyak]

Th400 and call it a day

Turbo and t56 makes as much sense as obama in office

Wow, the TH400 is a great price and holds a lot of power. I'd certainly like to have overdrive though! The car will see more street time than track time.

[somethingclever]

I would go auto for drag car with small cubes and forced induction and big power.

[Martin0660]

I would go auto for drag car with small cubes and forced induction and big power.

who hacked your account?

lol, I thought they had those 4r70w's pretty lined out some time ago. Seems like a logical choice

[yeahloh95]

you will break alot less parts with an auto , what rear gear does the car have now ?

[sutyak]

you will break alot less parts with an auto , what rear gear does the car have now ?

Stock 3.55 with 31 spline parts.

[somethingclever]

who hacked your account?

LOL...I was thinking as I was typing this...(Bob is gonna think WTF is he talking about?)



But to help make up Mark's mind, you should share how many rearend's and transmission's you have fragged to get something that works steadily. :)

[Stangman701]

Wow, if that built TR3650 really only needs a syncro I'd say that would be the way to go. Outside of that a T56 Magnum would get my vote. That's what I have in my cobra and it is awesome. It's almost worth the extra cash just for the better shifting over a regular T56. I wouldn't believe it if I'd never driven one, but it really is way better than a regular T56. Only down side is the shifter selection kinda sucks as it's a different bolt pattern on the tranny than the standard T56. I don't think you'd ever have to worry about the tranny after that until you got into four digit power levels and maybe not even then.

[George C]

355 gears and 28s with th400 cruise around 2800 at 65 mph

[sutyak]

355 gears and 28s with th400 cruise around 2800 at 65 mph

Not too bad. I run 315/35-17 on the street, so just under a 26" tire. 75mph is the new 65mph, too.

I'm leaning towards picking up that TR3650 and rebuilding it myself. If nothing else once I fix it I should easily get out of it what I put into it. I have absolutely no timeline I need to stick to, so I have time to change my mind. Rebuilding the TR3650 will be a nice winter project.

[Tom]

th400 for sure

[sutyak]

th400 for sure

TH400 looks like would be the cheapest/strongest route as far as an automatic goes, as long as the modifications required for speedometer and driveshaft are straightforward. I'm not sure what I think about cruising at 75mph at 3500 RPM. Can someone with a 3-speed chime in on how annoying it is to drive on the interstate with?

[Dan B.]

The Ranger has 3.55's, 28" rears and a three speed (C4). I've driven it some on the interstate. It's not that bad but depends on your exhaust and sensitivity to drone. I just love driving it so nothing bothers me.

[somethingclever]

no way would I have a modern street car with a trans that didn't have OD.

There are so many good options out there for electronic lockup convertors and OD transmissions that putting in a 3-speed just wouldn't make sense IMO.

Stronger and cheaper yes - but is it the right choice for the application?