Stock th400 vs 700r4 with shift kit

[Vbb199]

I have the tv cable set to about as far as you'd wanna set one to the high pressure side. It holds gear with light peddle into higher rpms of the gear. downshifts easily too...its not acting up at all. Its just a 700r4.
It could be partially due to the converter being a 2200stall and 2.76 gears, LOL. Once i have my 4.10s and 285/70s(30.5ish") I may just be right there with you. Hell 2nd is gonna feel like 1st does now,LOL... Ive looked over the trans ratios/gearing/tire size charts a dozen times and am pretty sure 4.10 is make me real happy.

Yep

 

[Frankenchevy]

Shitcan it, NV4500 swap

 

[Ricko1966]

Shitcan it, NV4500 swap

And an LS , wait did I just say that, never mind.

 

[Matt69olds]

I agree with the TV cable adjustment causing most of the failures. Too many people think flooring the gas pedals d calling it good.

First step to proper TV cable adjustment is to make sure the throttle fully opens when floored. Many times the floor mat, linkage flex, etc prevents WOT.

Gently accelerate, at the minimum speed the trans shifts into 4th gear, floor it, the trans should downshift to first. If not, the cable needs tightened another click or 2.

I didn’t mention the updated sprag, that slipped my mind.

Properly built, with the right parts, a 700/4L60 will reliably handle 500-550hp. Unfortunately, when you finally get the hydraulic pressure and friction material to handle some power, then you start to break parts.

In my opinion, it’s just not practical to use a 700 with big power. You can buy every aftermarket upgrade available, it’s still a weaker trand than a good junkyard 4L80 with a shift kit. If you have big power, absolutely have to have overdrive, and can make it fit, use a 4l80.

 

[Matt69olds]

[QUOTE="Matt69olds,

Totally with you on all points. However I dont need a 500+hp trans, I just want a smooth transition from 1-2 instead of babying it in 1rst only to have to get back in it a little in 2nd. Cant imagine how short 1st is gonna feel once i do gears. If im dogging on it i dont really notice as much but when just moseying around its a bit of an annoyance.
Id like to eventually go to either a 4l80 or 6l80 but cant justify doing that without going LS[/QUOTE]

The TransGo kit includes some parts to help out problems with the TV valve. It sounds like your may have some crud in it. Does the throttle go WOT with the gas pedal? If not, you may need to bend the throttle bracket a little.

 

[Matt69olds]

It’s possible to make a manual shift 4l80 without even removing the pan. There are YouTube videos on how to convert one for almost free.

Here is a manual shift control box
https://shop.jakesperformance.com/shop/ols/products/4l80e-manual-control-box

 

[Ricko1966]

It’s possible to make a manual shift 4l80 without even removing the pan. There are YouTube videos on how to convert one for almost free.

Here is a manual shift control box
https://shop.jakesperformance.com/shop/ols/products/4l80e-manual-control-box

Yea Jake's doesn't modulate line pressure. It runs max line pressure all the time. I don't like it. Also. I don't remember the exact sequence but it really wasn't hard to figure out. I did it with nothing but my phone to get a schematic, some speaker wire and some electrically tape to get the 6.2 4l80 I bought home from Columbia Missouri. The long and short is find the solenoid grounds neither grounded is 2nd gear 1 grounded is 1st the other grounded is 3rd gear both grounded is 4th gear. I just grounded them to the lighter socket to get home. But 2 toggle switches is all it takes. But again, no line pressure modulation bothers me.

 

[Matt69olds]

Fixed line pressure isn’t that big a deal as long as Teflon rings are used. Max line pressure on a 400 with a stock pressure regulator spring and 2 shims is around 180. I’m guessing a 4L80 pressure will be similar. The early 400 pumps are most affected by the load from fixed line pressure. The later designed pumps have a pocket machined into the casting behind the pump rotor. It’s purpose is to keep a little “bath” of trans fluid to lubricant the gear as it spins.

All of this is irrelevant to the op concern, guess I got a little sidetracked.

 

[Ricko1966]

Fixed line pressure isn’t that big a deal as long as Teflon rings are used. Max line pressure on a 400 with a stock pressure regulator spring and 2 shims is around 180. I’m guessing a 4L80 pressure will be similar. The early 400 pumps are most affected by the load from fixed line pressure. The later designed pumps have a pocket machined into the casting behind the pump rotor. It’s purpose is to keep a little “bath” of trans fluid to lubricant the gear as it spins.

All of this is irrelevant to the op concern, guess I got a little sidetracked.

Maybe so, but I appreciate the info. I was afraid running full line pressure full time would burn up the pump. Your not thinking so? Thanks for the info.

 

[Matt69olds]

People do it all the time. Obviously the pump won’t last as long as with modulated pressure, but its not like it will burn up in a hundred miles. The biggest concern is the load of fixed pressure on cast iron sealing rings. That will wear out the center support, pump support, direct drum, etc. Teflon rings solves the problem.

Most of my turbo LS buddies have street cars making 1400-1500 wheel hp, they have done several drag weeks, power tours, and every one of them have a transbrake. The 2 pump failures I can recall is one guy spin the stator support tube out of the pump. The converter was also trashed, but who knows what failed first? The other one also had a trashed converter, the fluid looked more like antiseize than ATF. About the only parts that were usable was the valve body and case.

Who would have imagined 15 years ago we would have been discussing transmission durability on 1500hp STREET cars???

 

[Ricko1966]

Well that sheds a whole new light on 4l80 swaps.10.00 dollars worth of scrap from the hardware store, and done.