let's chat

[95shaw]

The purpose of any discussion is to open the possibilities there are more ways to arrive at the same destination.

We both see that compromises are being made, both on restarts, and also on the long run.
We each see opportunites for gain in both areas with a 2 speed setup.

The direction we, or whoever tries this idea, may ultimately lead to confirmation, or rejection of this as a viable concept.

I see an opportunity to allow more top speed through final gearing, with the added benefit of better restarts.

Just putting it out there.


As far as rotating mass, there were stock case clutchless trans made by small shops in the early 90's. Being able to use 2 locked gearsets after getting rolling should be little problem with only a small gain in rotating mass.
Who says rotating mass is a bad thing on a momentum type track?

Finding the correct step in gearing to make max use of it may be the problem.

Anyway, fun to think about.

[ZERO25]

Rotating mass is the big dilemma......how much is too much? That's probly gonna be the biggest issue!

Just for fun, I thought about showing up with a 6 or 8 inch diameter driveshaft......that should get a few weird looks! lol

Most people in racing ask ..why......I like to say ..why not?

[fastford]

the lightest rotating mass from crank shaft to drive shaft i have ever seen was a 3 peed ford B&W with the second gear removed and the old cone type clutch , as close to strait drive as your gone get and very easy to adapt to that chevy bell housing , it also had an aluminum tail housing......

[Jking24]

Rotating mass is the big dilemma......how much is too much? That's probly gonna be the biggest issue!Just for fun, I thought about showing up with a 6 or 8 inch diameter driveshaft......that should get a few weird looks! lolMost people in racing ask ..why......I like to say ..why not?

We'll in this insistence the above mentioned driveshaft diameter. The seat belt bolt would likely be the "why not" but i like your thought process lol

[brad hibbard]

the lightest rotating mass from crank shaft to drive shaft i have ever seen was a 3 peed ford B&W with the second gear removed and the old cone type clutch , as close to strait drive as your gone get and very easy to adapt to that chevy bell housing , it also had an aluminum tail housing......

I am sure it has some sort of cluster shaft correct?
I think that is where the power get's gobbled up in conventional transmission vs bert/brinn style

[RW57]

I have seen people around here try a 602 to get the wgt break they all gave up went back to 604 you can't get car light enough to take advantage of weight break.

[fastford]

I am sure it has some sort of cluster shaft correct?
I think that is where the power get's gobbled up in conventional transmission vs bert/brinn style

it does but it can be modified and is very light to begin with , i was actually making a comparison to other factory 3 or 4 speed trans , should have clarified ,but in the end , i dont see no way to get a lighter rotating mass than a bert original style trans , which is lighter than a ball spline....

[ZERO25]

it does but it can be modified and is very light to begin with , i was actually making a comparison to other factory 3 or 4 speed trans , should have clarified ,but in the end , i dont see no way to get a lighter rotating mass than a bert original style trans , which is lighter than a ball spline....

Ive researched it quite a bit lately, you would be surprised how light some are......theres several that are around 75 lbs before any gears being removed or machine work being done! I just happen to know a guy! lol

[fastford]

zero ,i think your talking total weight , or at least i hope so because 75 lbs of rotating weight would make it a slug....

[ZERO25]

zero ,i think your talking total weight , or at least i hope so because 75 lbs of rotating weight would make it a slug....

Yes, before any gear removal or machining!

[Jking24]

The original brinn is less than 52# and the 2.0 predator is line 48#. That's alot of weight to lose. 75 lbs plus clutch and flywheel assembly. Im not familiar with the cone stuff but i can't imagine it doesn't way at least 10 plus pounds. So we're at nearly 35 pounds you have to loose just to be even. 602 434# 604 375# as delivered from gm so that's roughly 94lbs in the wrong direction. I still think it's not realistic to think that you will save any weight or gain any advantage on that front. Now will the ability to shift on restarts be able to outweigh this that remains to be seen. Btw all numbers i provided are directly from the manufacturers

[ZERO25]

Its definitely gonna be a balancing act. Hopefully, the concepts of momentum and pmi effects will all work in my favor.

Theres some transmission re-builders that rebuild stock type transmissions for circle track that are very light and frictionless coated but they are very pricey. I haven't ruled that out yet, but Im trying to find an affordable option.

Im not in a real hurry as we always disassemble our newly purchased cars completely and fix any issues we find before putting them back together. Im always amazed at how some guys think their body fabricators! smh,lol

[brad hibbard]

on this tranny subject---I just had a guy tell me that the 2nd gen bert has a chain inside
I have a hard time wrapping my head around any trans with a chain inside being less friction but there is no doubt that the 2nd gen bert free's up some power to the rear wheels
can someone expand on the internals of the newest BERT tranny to help me understand

Brad

https://www.race-1.com

[95shaw]

https://racecareng.com/tech-transmission-bert-gen-2-late-model-exploded-parts-view

or

https://www.speedwaymotors.com/Bert-Transmission-SG-1003-Late-Model-Input-Shaft,294875.html

[dirty white boy]

a bit heavier than a burt/brinn over all, but lightest stock trans reciprocating weight trans i know of!

https://www.youtube.com/watch?v=kEAaHjNuFV4&t=4s