I guess this goes out to both vendors, and everyone else.

I am looking for a T56 transmission to bolt onto a LS1/LS6 motor I am currently building. It will be a twin turbo motor, and I hope to be making over 700bhp. It is a long way in the future, but I want to buy the transmission now. ( exchange rates are good. Im in the United Kingdom. )
I require a suitable transmission and bellhousing to bolt to my engine block. I have been told that the Viper T56 is the one to go for as it is the strongest stock T56.
It is for a road car approx 3600lbs, with occasional track/strip useage. It will probably never be launched on slicks.
but...
I require a shifter position of around 27-29" measured from the engine mounting face of the bellhousing, to the shifter. The Viper box doesnt really give me this from dimension specs I have seen..
From specs I have read however, a 99 F-Body T56 gives me the dimensions I want.
I also require a mechanical speedo take off, and the tailshaft yoke, or possibly a complete propshaft ( or a cut off shaft to allow me to make a shaft to fit my car.)

I intend using a MCleod street twin clutch but I will not be purchasing this until I have a transmission.
I would also prefer the 5th-0.8 6th-0.62 ratio option, although that isnt very important.

Can anyone help ???
The TKO 600 would also be nice, but it doesnt seem to offer me the 29" I require, so I would prefer the 6speed route.

I am in the UK, so would require international shipping.

Thanks in advance, Stevie

 

I would probably start with a call to http://www.ddperformance.com - they can probably custom build to suit you - since they deal in all the styles & flavors of the T56. They do good work. I realize you're in the UK, and calling might not be the best option, but it may be the way to get exactly what you want/need.

Hope that helps!

 

Thanks, I did call DD a while ago. They probably do offer what I want, but they added some confusion.
The guy said their Viper box would give me the shifter postion I require. However, tremec's dimensions for the Viper box, on DD's website differed from what the guy was telling me on the phone, by about 3".
If the dimensions on the website are correct, then it would be no use to me, or very very difficult to adapt.
If the dimensions he told me on phone, and in email ( which varied twice ) then it would work.



Also, they could only offer me a transmission, no bellhousing. Without a knowledge of the various installations available for the T56 regarding bellhousings, I dont want to buy a box, and not know what bellhousing to buy.
I want a complete unit ready to bolt onto my engine.

As far as I see it, my requirements are simple, but nobody will give me a direct answer.
T56, good torque rating, 29" shifter postion measured from engine mating face. mechanical speedo, and a tailshaft yoke, or complete propshaft to fit.
And ready to bolt to my engine ( ie. complete with bellhousing )

Is it such a difficult combination to find ???

 

Steve, I`m in the middle of putting an Ls1 into my Capri and am also in the UK. Try going onto www.mcleodind.com. This company makes every bellhousing possible to fit any transmission to any engine and clutch assembly. they do development work for GM and Tremec etc etc. Phone their tech line (number on web site) and ask for Mr Red Roberts. he does the tech calls and knows what he`s talking about...he owns the company!(has done for donkeys years!) Their site lists every gearbox dimension you will ever need with hundreds of options. I am taking delivery of one of their modular bellhousings/clutch assemblies this week to fit my Tremec TKO 11 `box. Are you sure you want a six speed? With the sort of power your hoping for a conventional six speed may not last long. Take a long hard look at the new tremec 600 and explain your requirements to Mcleod.

 

The bellhousing isnt the problem. The shifter position is.
I think the T56 will handle the power. Most seem to rate the Viper T56 at 550lbft despite Tremecs claims, and there are so many people using it, with a lot more than that.
As I already said, the TKO is a no go. Shifter postion would end up inside the ashtray/centre console. It simply isnt an option.

DD said the viper box would give me a 29" position, but tremecs specs say it will be more like 26". Lowest I can go is about 27" and that is tight.
I dont want to carry out extensive bulkhead work when I fit the LS1, so the total box length must be right first time.

I'll do a bit more searching and waiting. I may end up just buying an F-Body T56, as it seems to offer everything dimensionally, apart from the torque rating. Or I may just buy the Viper one, and take DD at their word.