Is it a bad idea to lock up the TC at wot?
Say when youre going from a 40-60mph roll?

i have a vigilante 2800 9.5 tc...

EDIT: NEW QUESTION!
I just read this in the archives
My vigilante does that but I disconnected my speedo cable because I thought the wiring was screwed up... I guess i'll hook that back up asap...

anyway, would this slow my car down substantially since I have 2.77's? I think I remember the engine bogging a bit when it did that...


[This message has been edited by kream- (edited October 30, 2001).]

 

I am not sure what models lock the converter at WOT but trust me, the converter cannot do this on it's own. It is a programming issue. With a good tranny and converter I would not worry about it.

 

I have a (dana) pro-built 700r4, and the vigilante TC...
So the locking at WOT shouldn't cause any problems, and its safe to hook my speedo back up?

 

Sure.

 

From what I have heard about "locking the TCC" with the 700R4/4L60, it is both good and bad. When the TCC is not locked, the 700R4 does not move fluid through the tranny cooler. Which is pretty stupid design on GM's part as the time your REALLY want your tranny cooler to work IS during WOT. But conversely, with the stock TCC, WOT passes burns them up pretty fast and all that "crap" flows into the tranny itself.

So, because the fluid will not flow UNLESS your TCC is locked, you really DO want the TCC locked during WOT...just not with the stock TCC. The solution is a GOOD aftermarket TCC.

As for locking the TCC, you also need a change in the EPROM as mentioned. You need to set the "TCC Unlock Prevention Speed" inside the eprom from the stock 75 mph (on most TPI eproms) to a more reasonable number. I like around 40-45 mph. Helps with gas mileage also.

There are "modifications" you can make to the tranny to allow fluid to flow (partially) during WOT, but I will let the experts talk about that as this modification must be done VERY CAREFULLY or you'll loose all pressure. I personally don't recommend anyone other than those with experience even attempt this.

 

You both mentioned that the TC couldn't lock up on its own under WOT, you both say it would need to be changed in the programming.
I'm 98% sure I have a stock PROM. (when I bought my car the only non-stock items were tires and batt+alt)
I hooked my speedo. back up last night, and I'm 110% sure that the torque converter does lockup at WOT after 1st gear...
I have 2.77's so this bogs the engine a bit.. (perfect excuse to get gears )
Anyway, I'm just curious why this is doing it.. Maybe the new trans. has something to do with it??


[This message has been edited by kream- (edited October 31, 2001).]

 

I know that SOME cars can do a WOT shift into L/U. I am just not sure what ones. As far as as oil going through the tranny cooler there seems to be allot of missinformation about this. These are designed to move oil through the cooler AT ALL TIMES, it just takes a different path when in L/U.

Now that being said there are certain circumstances when oil flow is cut off but it is supposed to be only for an instant and you shouldn't ever notice it. That is at least how it is on paper. Under high demand and worse when hot, oil can be cut off and along with it goes lube oil. Fortunately, if you install any of the TransGo Shift Kits it will fix this. GM liked it so much that they COPIED it and incorporated it on all but the early 4L60e's!