T-56 with Solid Axle - FFCars.com : Factory Five Racing Discussion Forum

Nikoby · 10-04-2012, 02:01 PM

Hello All,

I really want a six-speed in my roadster, and I have a potential line on picking one up pretty cheaply. I also do not really have the funds to upgrade to IRS, so will be keeping the solid axle.

I know Sergio had stated that he is pretty sure that FFR moved the engine mounts forward in the chassis with one of their updates (between Mk2 and Mk3 IIFC). He surmised that with the motor mounts being moved forward, along with the added length of the T-56, would result in a virtually identical (and possibly even longer) driveshaft that the previous T-5 with a solid axle.

Can anyone confirm this?

I don't really want to get into a debate of whether or not a 6-speed is needed. I understand all the arguments on both sides. Everyone says...build it how you want. I want a 6-speed. So really looking for insight on how to make it happen with a solid axle.

Please support your statements with some type of empirical reasoning or first hand experience.

Thank you all in advance.

Nick

Scott Shumaker · 10-04-2012, 03:11 PM

Hey Nick,

What motor are you using? If you swap the motor mounts, it will move the motor forward about 2-3 inches. It might give you enough room to use the t-56.

Scott

MikeKelly · 10-04-2012, 03:37 PM

Speaking of reversing the motor mounts, you could also do the solid mounts and rearrange them a little and get a little more.

I used the CTS-V T56, which as you can see in the attachment is the shortest of the bunch. It's peculiarity is that it has a european style output flange for a Guibo joint rather than a slip yoke. That comes with its own set of problems, namely, you would need a slip joint in the driveshaft (for a solid axle) and the Guibo is going to be really (really) close to the 4" cross member (regardless).

With IRS, no Guibo, and rearranged motor mounts (mostly to get the bellhousing forward away from the diagonal braces in a Mk4) I ended up with a 10.5" driveshaft, u-joint to u-joint.

There's *some* room to move the engine forward if you want to cut the mounts off the 4" tubing, you might want to add a little for + aft gusseting to those while you're at it.

What I'm thinking is if you want to run a solid axle in a Mk4 with a T56 you'd probably better just plan on moving the frame mounts forward (not that big a job).

I can post pictures if you have any specific questions.

HTH,

Mike

MikeKelly · 10-04-2012, 03:42 PM

P.S.

The diagonal 1" tubing where the hand brake mounts also has to move if you're going to get the engine + tranny in anywhere close to straight.

You might be able to improve that situation when you move the frame mounts.

Mike

MikeKelly · 10-04-2012, 04:38 PM

Also, you can't go far forward with the engine before your FFR headers are useless.

Just another thought.

Mike

sharkx · 10-04-2012, 05:13 PM

I have a T56 behind a Ford FE. The FE's mount farther forward than the SBF engines. My FFR supplied 10.375" driveshaft was actually too short by over an inch.

The nature of your situation is going to depend on which version of the T56 you use as well as your choice of engines.

Bruce

MikeKelly · 10-04-2012, 05:33 PM

Quote:

Originally Posted by sharkx

The FE's mount farther forward than the SBF engines.

That explains why there's room to move a SBF forward. I didn't realize that.

I'm SBF BTW.

Mike

Also, the CTS-V Guibos are a dealer item. You have to buy the whole driveshaft to get them ($750 for those of you tracking the budget, lol).

Nikoby · 10-04-2012, 05:42 PM

Hey Scott,

Haven't spoken to you in a while. Thanks for input. Is it as simple as swapping the motor mounts side-to-side? How much extra room do you think that provides?

I'm using the 4.6 SOHC ('98 Mustang).

All others...

Good information. I don't really want to move the motor mounts forward because frame is already powder-coated.

It seems like there would have to be a way to gain enough room to accomplish this.

Mike Forte · 10-04-2012, 05:50 PM

Hi Nickoby,
If you install the engine mounts on the engine on opposite sides it will move the engine forward. With the engine forward the side pipes are no longer going to fit. You could either modify your side pipes or run under car exhaust.

MikeKelly · 10-04-2012, 06:10 PM

Quote:

Originally Posted by Nikoby

Is it as simple as swapping the motor mounts side-to-side? How much extra room do you think that provides?.

I could not get my SBF in there straight with the motor mounts either way (short of slotting the holes in the frame mounts). I ended up modifying solid motor mounts to put it where I wanted it. Don't know about the 4.6 mounts, but it's probably about an inch for SBF mounts.

Quote:

Originally Posted by Nikoby

because frame is already powder-coated

Remember, there are other problem areas to address, namely the handbrake mount and the rear 4" cross member (could be a problem).

Quote:

Originally Posted by Nikoby

It seems like there would have to be a way to gain enough room to accomplish this.

I don't know about that

And lastly, another option for CTS-V Guibos (I have one used for mock up only that I'd sell cheap!!!):

https://www.revshift.com/shop/drivet...sc-coupler.php

Mike Forte · 10-04-2012, 07:02 PM

Hi,
I make a CTSV 3 bolt flange to 1330 U-joint.

And lastly, another option for CTS-V Guibos (I have one used for mock up only that I'd sell cheap!!!):

Mike Forte · 10-04-2012, 08:26 PM

Hi,
This is my latest style I make. As most know it needs a plunge style drive shaft which I can supply if needed.

MikeKelly · 10-04-2012, 10:02 PM

That is a beauty.

Danner · 10-05-2012, 01:30 PM

I think choosing a 5 speed with perfect ratios for what you want, or going IRS, are going to be more reasonable and cost-smart than trying to do something quirky to squeeze this thing together.

I chose the IRS.

bbk347 · 10-06-2012, 09:56 AM

Nick. Building these cars is like playing dominos...you move 1 thing and it cause 6 other things to get moved. Listen to Danner. Good advice. If you absolutely must have a 6 speed, then put the IRS into it. You won't be losing any money that way. IRS cars are always worth more money (then cars that have adjusted motor mounts, wheelwell openings, header lengths, etc, etc,). If you add up what it will cost you to put a 6 spd in and keep the live axle, it'll be more I bet, then installing the IRS, and worth nothing on resale. Just my $.02

Mike Forte · 10-06-2012, 12:48 PM

Hi MikeKelly,
I thought of this style a couple years ago. I first made model in wood. Years ago I made one with a rear driveshaft flange from a Mustang. I like my second design best!!!

Quote:

Originally Posted by Mike Forte

Hi,
This is my latest style I make. As most know it needs a plunge style drive shaft which I can supply if needed.

MikeKelly · 10-07-2012, 02:42 AM

Quote:

Originally Posted by Mike Forte

I first made model in wood.

Most of my (no easy answer) stuff has gone to the 3rd or 4th revision in cardboard...

From there it goes 3rd to 6th revision in steel (or aluminum)...

Wonder if I'll live long enough to drive it? lol