TKO600 or T56

[Martin]

I've been deliberating the pros/cons of our TKO600 transmission choice for a while now. I had settled on the TKO600 as it will be more than strong enough for our planned HP/Torque (approx 450).

I couldn't decide between the 0.64 5th or the 0.82 5th with the TKO600 and that was the biggest debate I had. The T56 looks like it will give us the best of both worlds.

So strength aside (both should be strong enough), and apart from the extra $600 for the T56 what are the downsides?

Is the drive shaft too short with the T56? Are their problems fitting it in? Is there a mid shift option?

IRS standard width rear end if that helps. My understanding is that it "can fit", but that doesn't mean it is a good fit. It will mainly be used as a weekend cruiser, with 3-4 open track days every year. Not worried about the fastest lap, but want to have fun at the open track days without worrying that I might break something.

If the T56 can fit without major problems I'll happily go down that route.

Any thoughts appreciated.

Martin

[Wayne Presley]

Only use the T56 with IRS due to the short driveshaft length. I like the TKO 600 with the .62 5th and I'm getting 22 mpg with a 705 RWHP roadster with one in mine.

[Martin]

Is having a short drive shaft length to fit the T56 a problem? Or is the fact that it is shorter make no difference?

[Wayne Presley]

Only with the 4 link/3 link solid rear axle due to the U joint binding with axle movement.

[Hankl]

Is having a short drive shaft length to fit the T56 a problem? Or is the fact that it is shorter make no difference?

The drive shaft with the T56 would be extremely short, just a few inches between the universal joints, not an optimum situation. As to the final 5th ratio, if your are looking for gas milage, and your overall intended use the .62.


Hank :cool:

[Martin]

Sounds like the TKO600 with 0.62 (0.64) 5th is the way to go. Does the short drive shaft length with only a few inches between the universal joints cause strength issues?

[Wayne Presley]

No strength issues.

[Martin]

So what isn't optimal about it if strength isn't an issue?

I know next to nothing about cars, but I understand the basics of physics and I can't see a problem with a short drive shaft. I must be missing something.

Martin



The drive shaft with the T56 would be extremely short, just a few inches between the universal joints, not an optimum situation. As to the final 5th ratio, if your are looking for gas milage, and your overall intended use the .62.


Hank :cool:

[snakeboost]

The drive shaft can bind up if too short.....Not a problem if IRS......The new magnum is available midshifted but I have been told you only need to flip the shifter around to get it to fit close

Steve

[Martin]

Any need to cut the transmission tunnel? I think we need to for the TKO600 if a midshift option is chosen.


The drive shaft can bind up if too short.....Not a problem if IRS......The new magnum is available midshifted but I have been told you only need to flip the shifter around to get it to fit close

Steve

[snakeboost]

I do not think so......only had a couple go out
Steve

[JGPierce]

I just installed a T-56 Magnum that I purchased from Fortes. Like you, I wanted the gearing. The driveshaft needs to be custom length (11-15/16" with my 4.6L 3V). The Driveshaft Shop can easily make you one. The only other change is to weld a 1/4" plate to the top of the FFR tranny mount and drill new holes for the tranny. The T-56 sits lower and the standard FFR hole distances don't work. Very easy mods.

The T-56 rear and mid mount are made by unbolting the tranny cover and turning it 180 degrees. I cut the 3/4" cross member on the top of the tranny tunnel while I was modding it for a top mounted e-brake.


John

[Martin]

John - thanks for a great answer. Did fortes also provide your drive shaft?

[JGPierce]

The Driveshaft Shop made it. They make all the driveshafts for FFR.

[efnfast]

Have you looked at Levy Racing's alloy T5 transmission? it's lighter than the tko, can handle more power, shifts better, can come pre-assembled as mid-shift .... basically just an excellent all-around tranny.

I've had mine for 3yrs and absolutely love it and glad I went that route.

[Martin]

I did look at it.

Not sure the gearing is right for me though. It's also hard to get someone to commit to a "it can cope with XYZ HP/TQ" number for it. We are only aiming for 450 to begin with, but are building it to be as solid as possible in case we get an itch to upgrade later. At least with a TKO600 I know if we have a bit of a buffer.

I see you have 490HP which means there must be some buffer, but so far, I haven't been able to get a definitive number.

Martin







Have you looked at Levy Racing's alloy T5 transmission? it's lighter than the tko, can handle more power, shifts better, can come pre-assembled as mid-shift .... basically just an excellent all-around tranny.

I've had mine for 3yrs and absolutely love it and glad I went that route.

[Brian Z]

You will have to modify the bolt on transmission mount with a T-56 in the Mk4. The plate will have to be cut and rewelded as the T-56 is longer in the back. We have one in our 3V 4.6 car in the showroom. It has a 3-link rear suspension and we haven't had any issues yet. We usually advise against the T-56 as it is not a direct bolt in.

A 302 engine with a T-56 is longer than a 4.6 with a T-56.

Best regards,

[efnfast]

I did look at it.

Not sure the gearing is right for me though. It's also hard to get someone to commit to a "it can cope with XYZ HP/TQ" number for it. We are only aiming for 450 to begin with, but are building it to be as solid as possible in case we get an itch to upgrade later. At least with a TKO600 I know if we have a bit of a buffer.

I see you have 490HP which means there must be some buffer, but so far, I haven't been able to get a definitive number.

Martin

490RWhp on the dyno, which is around 600hp depending on the drivetrain loss.

[JGPierce]

Martin,

If you go with the T-56 Magnum give me a PM. Here's a picture of how to modify the tranny mount. Very easy to do.

2589

[Martin]

What about a 351w and the t56?


You will have to modify the bolt on transmission mount with a T-56 in the Mk4. The plate will have to be cut and rewelded as the T-56 is longer in the back. We have one in our 3V 4.6 car in the showroom. It has a 3-link rear suspension and we haven't had any issues yet. We usually advise against the T-56 as it is not a direct bolt in.

A 302 engine with a T-56 is longer than a 4.6 with a T-56.

Best regards,

[Brian Z]

The 351w and the 302 have the same bell housings. It would sit the same as a 302 with a T-56.

[BigLeo69]

couldn't you move the engine mounts forward to make the t-56 fit, aren't you changing the steering to the passenger side. Fezzek

i got the tko-600 w/.82 may think about matching the rear ratio, tire size, and cam set-up.

[Martin]

Yes. We are swapping to rhd. We've got plans to shift the engine to centre it, so moving It forward a bit is only a little bit more work. Standard width irs with 3.27 torsen t2.

[BigLeo69]

Yes. We are swapping to rhd. We've got plans to shift the engine to centre it, so moving It forward a bit is only a little bit more work. Standard width irs with 3.27 torsen t2.

then i like the thought of the t-56 hydraulic clutch
its wider but putting it forward would alow more room, and with footbox mods that you will be doing, the tig-rig is already to go...cut grind and weld...good luck my friend, we just had a visit over here from some of my brothers Irish lads i come to find they like Bailey's by the bottle.
tell me how can i get a BMW with a side car over on your island and not have to pay such enormous taxes, my brothers friend passed away and his wife wants his brothers to have it but it cost so much to get it there, any loop holes.
thanks

[sharkx]

With regard to the length of the T56, here's a picture of a T56 vs a T5:
http://www.linux2go.org/postings/t5vt56.jpg

The big difference is that the mount point is further back. In many cases, the FFR supplied driveshaft will be too short not too long. I ordered the 31 spline 10.375" FFR driveshaft and was surprised to find that I needed a 10.875" driveshaft.

Here's another picture of the tranny mount that's been modified. The webbing is cut away and a 1/4" plate is welded on top. It's an easy mod.

http://www.linux2go.org/postings/crossmember.jpg

Bruce

[Martin]

That's a great picture and very helpful.

Many thanks.

Martin