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K.. I was just wonderin.. I plan on many a road trip with my Bullitt so I don't want to gear it to death, but I think I may have stumbled upon a solution, but I'll need the help of those more knowledgeable about this.
If I opt for the 4:10's would the 6 speed tranny negate the ill effects of highway cruising by having the extra gear in the trans?
I 'm aware this is an expensive proposition, but hell.. the 6 speed is a tougher tranny anyhow. I guess I'm just looking for a way to have my cake and eat it too.
 

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It's certainly doable. The parts are available to swap in a T56. It would be expensive though. The biggest thing is where the shifter winds up being located due to the t56's longer length.

I think the final 6th gear rati in the T56 is taller than our fifth, so you could install 410's and still have decent cruise rpm in 6th.

Brian
 

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I have a modular specific T56 6speed in my 98 Cobra equipped with 4.10s out rear. I had gone through 2 T45 trannies and decided enough was enough.

It does have a taller 6th gear as compared to the T45 5th, but not by much. The 6th is a .62 abd the T45 5th is .67. It will lower your RPMs at 70mph by around 200 clicks.

I wish Tremec would have made a .50 6th an option, but they didn't. I inquired from a couple of places how much it would cost to get a custom 6th gear, and quite frankly, it was outrageous. It's still a great tranny the way it is and will provide over 400ft lbs of tourque capability. More than enough for most mortal Bullitts.

If you're really serious, I can tell you what all is needed for the swap.
 

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JB, I would be interested in what is required too.

Brian
 

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<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2001-11-16 10:43, JB VOBRA wrote:
I have a modular specific T56 6speed in my 98 Cobra equipped with 4.10s out rear. I had gone through 2 T45 trannies and decided enough was enough.

It does have a taller 6th gear as compared to the T45 5th, but not by much. The 6th is a .62 abd the T45 5th is .67. It will lower your RPMs at 70mph by around 200 clicks.
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>
That pretty much sums things up... more gears usually means gears closer together rather than more up on top. The narrower the powerband the more gears you need/want. Remember Mustangs once had 3 and 4 speeds. OTOH the Honda S2000 has 6 speeds. For a street car I don't want to have to work quite that hard, so I bought a V8.

Now a 6 speed with stock or a slight rear end could be an interesting combination. How do the first couple of gears compare?

OTOH more gears means more time not putting down power because you are shifting.
 

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it's really straight-forward. You can get the tranny from several places now, like D&D Performance (248-926-6220). You'll need the tranny (bellhousing matches up perfectly, no modification needed), a shorter driveshaft (I had my FMS alum d/s shortened around 1"), a GM tranny mount, your clutch is reusable if you choose, and that's about it!

The tranny mount will need to move forward from the current location. I personally didn't install mine, I had Steve Drier at Houston Perf do the work. But according the mechanic, it wasn't "rocket science" and this was the first modular T56 he had ever installed.

As far as driving, it is excellent. The 1-2 shift is really close ratio from the T45(3650) tranny. 1st gear is 2.97 and 2nd is 2.07. Quite a different sensation from the 1-2 shift on the Bullitt (3.37 to 1.99). I love it, and I'm pretty darn sure most of you would as well.
 

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JB.. Wow, I was expecting it to more complicated than that. I new the bell housing would be right, they make 3 bell housings for the T56 for Ford, GM and the Viper. I thought more parts would be needed, cool.

Thanks!

Brian
 

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Well, wouldn't it be better to follow along the lines of something like this:
1st - 3.37
2nd - 2.45
3rd - 1.88
4th - 1.35
5th - 1.00
6th - 0.60

Something along that line so you'd still have a quick first with a moderate 2nd and 3rd gear before cruising at 4th and 5th.
 

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You might want to look into the new 2002 tremec that is going into the Mustangs. I read somewhere that it has a different 5th gear than we do. I don't know any numbers but it should help.

just my 2 cents. :grin:
 
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