I'm rebuilding my 700r4 w/ upgraded clutches, kevlar bands, corvette servo, light weight drum and shift kit.
I'm wanting to find out if anyone has ever used the B&M peice that lets you go into 4th under full throttle and how that works. Right now my top end is limited to ~145 because I just red line in 3rd. I'd like to pick up another 15-20 mph because I'm going to run in the Silver State.
Will this do it for me?

 

Yes it will work,it will allow the tranny to shift into 4th at WOT.

 

Is this in the 1/4 mile? If so you better put in a tranny shield because that 700 will be sticking through your leg with that type of stress. I have had three rebuilds in three years with mine. The next step is a TH400.

 

Thats all I needed to know. I'm pushing 385 at the tires and needed a little bit more top end to take up any slack. I'm hoping that it doesn't lag too much, even it it will just let me cruise at that speed will be great.
I'm going this route because swapping to the 3.08 or lower would kill me out of the turns.

 

Funny thing...RacinLt1's 4L60E Has lasted 2 seasons running 11.2's. Don't be so hasty to put the 700/4L60E down until you have someone build it that knows what they're doing. I've got 700's out there running in the 10's.
I will advise against using a Kevlar 2-4 band, though. I use Alto "Wide" RED lined bands in all my racing transmissions. The Kevlar seems to be too hard of a material. I've seen alot more of the Kevlar burn up.

 

Sorry...To answer the original question...Yes the TV plunger and sleeve will allow the trans. to shift into 4th at WOT.

 

I'm running this trans in an open road car. It will be used for some drag racing but the car isn't set up right to need 4th in the 1/4. I'm focusing more on running flat out for 90 miles. I believe he suggested the Alto band instead, I told him to go w/ what he felt would work best.

 

Stay with the Borg Warner Hi-Energy 2-4 band, it's proven. The Alto extra-wide "red lined" band is ok, I have not seen the need for it as of yet. As for Kevlar it produces to much heat from its lack of "holding power". This is kind of an oxymoron, Kevlar is supposed to take the heat, but at the same time it produces more than it should from slipping. I have of yet seen Kevlar work better in "any" situation. You can modify the TV plunger sleeve by blocking the 4-3 part throttle passages with two small Allen screws, (.34 cents total), this will allow 3-4 WOT shifts.

 

The B-W band is alright, but I stay away from it in high HP applications. I haven't had any failures in any of my 10-11 second 700/4L60E's yet. They're pretty much a neccessity when using a billet servo.
Yes, you can modify the TV plunger yourself. We've done alot of them with aluminum slugs, and then machined them. Older police 700's had them in them from the factory.

 

I haven't had any failures using Borg Warner Hi-Energy 2-4 bands and Corvette servo in my 10 & 11 second 700R4/4L60E's either. If your setup works for you great, I find that this gets the results I want (and for less). So I guess it is a matter of "preference.

 

Very true. You'll hardly ever find 2 transmission builders that build the same way. Even those working at the same shops practice different technics.