Page 2 of 2

Re: Made it to the 4.70's

Posted: Tue Aug 04, 2015 7:43 am
by ytnova
The biggest advantage is the increased availability of gear choices, with the glide case, you are physically limited in size with what gear you can run due to the case being smaller in diameter than a th400. I think the smallest numerical gear for a glide is in the 1.6x range. The current train of thought is to make the gear spread between high and low closer so it does not upset/unload the chassis between shifts, unload or drastically change the load on the tire between shifts, and keep the engine in the peak power/torque band. With limited width tires and/or radials, the goal is to apply as much power as you can as smoothly as you can without upsetting anything. A th400 also has larger diameter clutch packs with more available clutches, ie more clutch surface area, to increase its holding capacity.

Re: Made it to the 4.70's

Posted: Tue Aug 04, 2015 7:53 am
by Bruce69Camaro
Ok, so does this 2 spd 400 have internals of a P/G or is all of the internals custom or can internals from a 400 be used?

I never heard of this type of tranny.

Re: Made it to the 4.70's

Posted: Tue Aug 04, 2015 8:07 am
by John_Heard
The 400 is stronger, but the big deal is the gear ratios available for the 400. Many are using 2 speed 400s, for example launching on the 1.48 (2nd) gear. There are a ton of ratios available for it. 400 is also approx 13 lbs heavier, which sucks.

Re: Made it to the 4.70's

Posted: Tue Aug 04, 2015 8:11 am
by Bruce69Camaro
So you lose 15 lbs. off the belly and you'll be good...LOL

Re: Made it to the 4.70's

Posted: Tue Aug 04, 2015 9:11 am
by John_Heard
No doubt I'm carrying at least that much extra. I'm just saving that as a final weight reduction when I can't find anything else on the car!

Re: Made it to the 4.70's

Posted: Fri Aug 21, 2015 8:08 am
by John_Heard
Image
Got a new PB at the Throwdown in T-Town, 4.77@150.77

1st round of eliminations it decided to stand up, did a 1.20 60' on the back tires, unfortunately it went right and I had to chop it, probably a good idea as it was still coming up too. We stuck 25 lbs in the nose and tightened shocks up for E2, wasn't quite quick enough for Taylor Lastor, he went 4.74 to my 4.77 and went on to win in the finals over Kit Loung. Good race, we got to test a few ideas and learned a few things so maybe we can make some more improvements next time out.

Re: Made it to the 4.70's

Posted: Mon Aug 24, 2015 6:44 pm
by wheels
What a great picture. Nice to hear you are having success this season.

Re: Made it to the 4.70's

Posted: Tue Nov 24, 2015 2:36 pm
by wikd69
I know I'm coming in late to the party, but what the heck is a 2-speed 400 ?

Re: Made it to the 4.70's

Posted: Tue Nov 24, 2015 3:27 pm
by John_Heard
Transmission shops have been selling Turbo 400's that are converted over to 2-speeds to take advantage of a tall 1st gear, like a 1.48 or other ratios. Some are setup as 3 speeds that can launch (transbrake) in either 1st or 2nd. These are very popular in X275 cars and faster classes.

Re: Made it to the 4.70's

Posted: Thu Nov 26, 2015 12:40 pm
by wikd69
Wow, that's wild !!! I'd never heard of that before.