New TRT Transaxle

[Steve Briscoe]

Richard -
Thank you for the creativity and what looks to be a really good option. Are you looking for an SPF test car with a 427? Also, have you had time to consider what the warranty will be like?

Thanks again-
Steve

 

[Eric A.]

Will the synchro box have straight cut or helical gears? I am sure that those who are going to use these in a car mainly for street use would prefer the helical gears if they will be available.

 

[charlie]

Will the syncro box also be sequential ?

Charlie

 

[Richard Timte]

Eric,

To answer your question, yes the syncro box will have helical gears.

Charlie,

Both boxes the TRT 800 (straight cut gears and dog engagement) and the TRT 600 (helical gears and syncro engagement) will be both h-pattern and sequentially shifted. As I said before, the same transaxle can run both ways with just a few part being swapped out. I will give out more information on how this is done in the short future. Now each version TRT 800 or TRT 600 are just that and can't changed. So the TRT 800 (straight cut gears and dog engagement) can't be changed to the TRT 600 (helical gears and syncro engagement) or the other way.

Thanks again for your interest.

 

[Richard]

Bravo, Richard

The topic of someone on the Forum designing their own transaxle for manufacture has come up time and time again.

I'm very keen to see how your syncro/helical unit develops.

I'm watching with interest!

 

[Ian K]

ZF - 450 ft lbs max (9,000 US plus you need a bell housing)

Richard, I'm confused. What makes you think the ZF cannot handle the power
of a modern V8? With some paractical upgrades, the Pantera crowd has 800+ HP
and 500 lbs/ft pushing through them pretty reliably.

Ian

 

[Richard Timte]

Ian,

I can't find the picture, but a gt40s member sent it to me. It was a picture of what forth gear looked like after rolling on the throttle on a 550 hp Pantera (no teeth left). This happened three times and he finally decided to upgrade the gears to straight cut because of the rebuild costs (RBT). Can a ZF work, sure but when you have torque it will take its toll. Thats why they created the T44. The ZF would not handle the torque.

And the debate goes on

 

[Sandy]

Richard -

It was that picture and Fran's pestring me to run a 930 that swayed me from the ZF. I think it may be in one of my old old theads when I was asking about cars a boxes. I'll see if I can dig it up.

Sandy

 

[Ron McCall]

All I know is that the ZF in my Pantera took all of the abuse I could give it for over a year and several track events.That's with 670hp and 510lbft!!!
And believe me I was NOT easy on it!!!

 

[Russ Noble]

Maybe should start a new thread on ZF failures and see what comes up, and leave this thread for TRT? I might start the ball rolling...

Try this http://www.gt40s.com/forum/gt40-tech-powertrain-transaxles/20804-zf-failure.html#post181988

Cheers

 

[BruceA]

Ian,

I can't find the picture, but a gt40s member sent it to me. It was a picture of what forth gear looked like after rolling on the throttle on a 550 hp Pantera (no teeth left). This happened three times and he finally decided to upgrade the gears to straight cut because of the rebuild costs (RBT). Can a ZF work, sure but when you have torque it will take its toll. Thats why they created the T44. The ZF would not handle the torque.

And the debate goes on

You're saying the teeth stripped off 4th gear which was a helical cut gear, and you put in straight cut gears.
Someone correct me if Im wrong, but helical cut gears are in general stronger than straight cut gears. The length of the tooth face surface contact is longer on a helical cut gear. The only reason one would use a straight cut gear is for the minimal amount of power gained due to not having the gear teeth sliding over each other, and of course the reduction in heat generated from this sliding and less power used when the shafts are being pushed apposingly against the thrust bearings. And we are talking minimal here ....
I would think that the tooth size and shape, material and hardening would have more to do with gear strength than the cut.

 

[Randy V]

You're saying the teeth stripped off 4th gear which was a helical cut gear, and you put in straight cut gears.
Someone correct me if Im wrong, but helical cut gears are in general stronger than straight cut gears. The length of the tooth face surface contact is longer on a helical cut gear. The only reason one would use a straight cut gear is for the minimal amount of power gained due to not having the gear teeth sliding over each other, and of course the reduction in heat generated from this sliding and less power used when the shafts are being pushed apposingly against the thrust bearings. And we are talking minimal here ....
I would think that the tooth size and shape, material and hardening would have more to do with gear strength than the cut.

I'm not familiar with the particular transmissions being discussed but am familiar with a number of others. Here's how it works (in them).
With helical cut gears, there are more of them - say 30 on a particular gear.
The same ratio in a straight cut gear would yield 25 teeth.
The base and contact area of the straight-cut gear is substantially wider than that of the helical gear.
The abrupt contact area of the straight cut gear makes it noisier than the helical cut gear.
The image below shows the contact patch but does not illustrate the difference in base widths;

There are trade-offs between the two designs. I think that the primary trade-off that was made was to reduce the noise at the price of strength.
Since transmissions are manufactured with a "fixed" center spacing between the main and countershafts, the only way to substantially increase the strength of the gears is to flatten out the helix in them and either make them at a substantially reduced helix or no helix at all (straight)..

 

[Ron Earp]

Maybe should start a new thread on ZF failures and see what comes up, and leave this thread for TRT? I might start the ball rolling...

Try this http://www.gt40s.com/forum/gt40-tech-powertrain-transaxles/20804-zf-failure.html#post181988

Cheers

I'd second that. This forum is for Supporting Manufactuers to annouce new products and inform the membership of their wares. It isn't for a thread on discussing the merits of products or technical discussions.

Ron

 

[Richard Timte]

Thanks Bigfoot,

I was going to respond to RamboLambo comment:

"but helical cut gears are in general stronger than straight cut gears."

I don't know where you got your information, but its just the opposite (less teeth which equals more root in the same ratio of gear, plus the contact patch is a lot bigger which means more area to transferring the power). Also, not one race box has helical gears, because it takes 1.5 to 1.75 times the weight to transfer the same amount of power (wider or bigger diameter gears). There are many books on this and I suggest we take this offline or to another thread.

Thanks Ron,

We had a couple of drifts, but that's not a problem as some good info came up.

Here is an update:

Interest has been good and the order list keeps getting longer every day. I am not taking any substantial deposits just a check for $10.00 to put your name on the list. My business partner came up with the $10.00 to keep the list down to real customers. If you are really interested you would spend the time to write a letter and send the $10.00 check. If you wish to take your name off the list I will mail you your check back. Target date for the prototype box has not changed and my &*^@#$ lawyer still won't let me release any drawings.

Thanks again

 

[Gregg]

Richard, I don't see the need to denigrate your lawyer. He is acting to protect YOUR interests, isn't he? If you don't want to follow his advice, post away the pictures.

 

[Mark Worthington]

Guys, I've seen some of the work that Richard has done, and if anybody can pull this off, he can.

Richard, what a great idea. If/when I build my next mid-engine car I want it to have a TRT transaxle. I wish you the best in your business endeavor.

 

[Jim Holden]

Can you post a pcture of what the transaxle case will look like?

Kim

 

[Gary Kadrmas]

Richard,

Once the legalbeagles have had their day, and everything is well in place to protect the interests of those that require protection,....errrrrrr,

the lesser technical folks like myself would like to be able to compare the
dimensions of your box to the size of a ZF. For me, the GT40 I have in mind is set up to accomidate a ZF easily. So any information you could share with us, along with something along the lines of a visual would be quite welcome. The ability to easily change gear ratios is way good.

Thanks,

Gary Kadrmas

 

[Richard Timte]

Gregg,

I know, it is driving me crazy . I have nothing against lawyers, my daughter is becoming one, my brother and sister-in-law are lawyers and my lawyer is the best and he is definitely looking out for my interest. Its just frustrating trying to explain certain things while holding valuable info back. If I offended anyone I'm sorry.

Mark,

Thanks for the kind words and when you build your next car give me a call, I will hook you up.

Kim,

In due time (sorry).

Gary,

Below are two differences (size and mounting) between the ZF and my box. I don't have a ZF to get other dimensions but will give you mine.

1. There are no support mounts on the box like the ZF.
2. The ZF is 10.125 from the block surface to the center line of half shafts, mine is 8.25.

Overall length with bell housing is 24 inches.
Length from centerline of half shafts to back of box is 15.75 inches.
Height from bottom of box to centerline of input shaft is 4 inches.
Height from centerline of input shafts to top of box is 10.5.
Almost 13 inches wide.

If you need any other measurement just ask.

Thanks again for the questions

 

[Brian Kissel]

Hello Richard !!!
I'm sure you have heard this before. but " the check will be in the mail ", as I am VERY interested. I am currently researching some things, that I would like to discuss with you. As soon as I get a little more information (factual), I'll give you a call.
THANK YOU for your time, and consideration !!!!!!!!!

Regards Brian

I'm glad I previewed this reply. I went back and reread all the replys, and noticed I don't have your address to send the check to. You have my email address, from my previous questions, so please send your details there.

THANKS AGAIN !!!!!!!!!!!!!