NT788 Chassis Replacement Fabrication

[kiwi belly tank]

That's my kinda stuff right there! 8-) What's your ratio & what is that, a Dana 60 pinion with a semi axle gear?
  Sid.

[turborick]

That's my kinda stuff right there! 8-) What's your ratio & what is that, a Dana 60 pinion with a semi axle gear?
  Sid.

its a champ pinion shaft and yes a semi spider gear. the ratio is 1.78
the ring gear is only 5"

[turborick]

anyone ever try burnishing gear teeth with Moly?
how about using Moly as an additive to the oil in a rear end?

[manta22]

anyone ever try burnishing gear teeth with Moly?
how about using Moly as an additive to the oil in a rear end?

No, Rick, but I did know of a fellow who burnished his gears with a can of Brass-O.

Regards, Neil  Tucson, AZ

[Rex Schimmer]

Rick,
I have always admired the stuff that you build, your original NT III with the turbo Busa was probably one of the most impressive cars to ever run at the salt. Now your adaption of a turbo SBC into the NT III chassis is a marvel of packaging, engineering and fabrication. (OK here it comes) BUT what appears to be your design for a final drive really looks like it could be marginal at best. Using a 25 inch tire diameter (not considering tire growth at 400 mph, which could be considerable) I get a tire-ring gear speed of approx 5400 rpm and a pinion speed of 9600 rpm and you are going to put probably as much as 1500+ hp through a straight bevel pinion gear with 9 teeth and a ring gear with 16 teeth. I cannot say that I am optimistic about this working. Have you had anyone look at the tooth loads and cooling requirements for this drive?

Rex

[turborick]

Rick,
I have always admired the stuff that you build, your original NT III with the turbo Busa was probably one of the most impressive cars to ever run at the salt. Now your adaption of a turbo SBC into the NT III chassis is a marvel of packaging, engineering and fabrication. (OK here it comes) BUT what appears to be your design for a final drive really looks like it could be marginal at best. Using a 25 inch tire diameter (not considering tire growth at 400 mph, which could be considerable) I get a tire-ring gear speed of approx 5400 rpm and a pinion speed of 9600 rpm and you are going to put probably as much as 1500+ hp through a straight bevel pinion gear with 9 teeth and a ring gear with 16 teeth. I cannot say that I am optimistic about this working. Have you had anyone look at the tooth loads and cooling requirements for this drive?

Rex

Hi Rex Thanks
Jack and I and my team definitely have had good luck with NT II. NT III has been a little struggle but will get there.
The straight bevel gears have been in use on NT III for many years with up to 800hp and other than wear they are still alive.
in the past we used ATF in the diff and that was a bad idea, i'm guessing most the wear came from using the wrong lubricant.
I don't think we will dial in more than 8 or 900hp this year as we will be taking baby steps with our program, we can't afford to break anything so we need to race smart. In the future I can see the need of a stronger design but we will try, the car is light and we have a torque converter both those things should help the drive line live, then we can also play with torque management. To answer your question no I never had anyone look at the requirements for the drive.

[SPARKY]

 

[kiwi belly tank]

Go to SAE-50 synthetic trans fluid, that's what semi transmissions use with huge tooth loading plus it's thin enough to pump if you use one.
 Sid.
ps Have you looked into industrial right angle drive boxes? They have bevel gears with more tooth contact.

[turborick]

Go to SAE-50 synthetic trans fluid, that's what semi transmissions use with huge tooth loading plus it's thin enough to pump if you use one.
 Sid.
ps Have you looked into industrial right angle drive boxes? They have bevel gears with more tooth contact.

Thanks Sid I am investigating the oil situation I have some heavy synthetic gear oil to start out with and I will try burnishing with moly.
the industrial right angle drive boxes look interesting  have you done any research on them?

[kiwi belly tank]

I did look into using some 1 to 1 bevel gears for my liner when I started building about 6 yrs ago but I just don't have the machining capability to build all the rest of the stuff so I used a pair of 10 bolt centers with 2.136 gears & put direct/overdrive units on the front of them to end up with .962 final.
There are some ratio's available off the shelf in bevel gears.
I also built a front reverser transfer case using 8" gears from a Funk Drive pump case.
  Sid.

[MattGuzzetta]

If my memory is correct, Don  Vesco used industrial right angle drives in the Turbinator and told me that they were trouble free with all the torque the turbine (T-55 methinks) put out. They were for 50 HP electric motors.  You can ask Rick Vesco to see if that is correct.    I do remember being impressed.  The industrial units are for heavy use, 24-7, so they may be way overbuilt.  The cases are probably heavy, but worth a look.
Hope this helps.....

Matt Guzzetta

[Ron Gibson]

IIRC the Burkland liner uses 1 to 1  90 degree drives out of one of those large rotating billboards.

Ron

[grumm441]

anyone ever try burnishing gear teeth with Moly?
how about using Moly as an additive to the oil in a rear end?

Yep
I put a moly additive in the gearbox and diff in our bellytank
G

[turborick]

Thanks for the reply's guys, I will investigate the angle drives in the future for now El Mirage is only 3 weeks away

[kiwi belly tank]

This would be the time to say good luck Rick but I'm a big proponent of good management so have at it & I'm interested to see how it all works out.
The first time a saw a rotary sign gearbox use as a drive axle was in Nolan White's Spirit-of-Autopower liner back in the 80's so they can apparently handle gobbs of power.
  Sid.