HighPerformanceTrucks
Lift & Shift Specialist
For those of you who swapped in a 4l80E for the old 700R4, I would be interested to hear your impressions related to the 2:48 1st gear.
George Blake said:You didn't believe me?
We talked about it several times.
I'll type it out here.
What I found out when we got Tasos's truck into the low 10s high 9s is the 1st gear in the 700 becomes totally useless at those levels. Basically the tires burn off and the truck kinda crawls due to tire spin until you hit 2nd and then you actually start moving.
On the 80, the 1st gear ratio is much more attune to hard takeoff and you can hold 1st gear to a higher MPH. This gives you better time on the hole shot. Where the 700 immediately runs out of steam and has to shift, 80e is still working propelling you forward.
Now what your gonna see driving through the turns is that your gonna require MUCH less shifting because your gonna be driving at a higher mph in first and still making torque.
Again, 700 was used by GM because it was a cheap smog trans with a good 4th gear that came out in 1984. 80e was a workhorse DESIGNED to take torque and heavy loads and came out in 91 and perfected in 1999. Much newer technology but it's not a cheap trans for GM to be able to make money on.
Remember. If GM can swap out a bolt for a plastic christmas tree to hold a piece on to save 5 cents on 200,000 units, they did. This is why you never saw the 80e in the corvette or the syty's.
George Blake said:Look. I'm not being defensive. I've answered these questions already and it gives the impression that my time was wasted on all those calls and yes, it bothers me.
As far as the physics lesson comment, I'm lost. That's how they work. There's no magic. That's just how it works and that's what you will experience. As far as getting feedback from others....you won't find anyone doing what you are doing. Hillclimbs, course racing, and other event type activities. The closest thing to what you are doing with the 4L80e was the "555 Sy" and he was making a LOT more power than you are (at least for now). So your on your own for right now and others will be looking to you. Get some road time in and have some fun and most of all.....![]()
QUIT WORRYING ABOUT IT.
Have some frigging fun with it for God's sake.
BTW, I've got that magnet to put on your tailgate at the events. I'll get it out ASAP.
George Blake said:I sent you an email with a different program to put into T-com.
George Blake said:If you want really aggressive shifts, flip that switch I told you about.
Tire diameter and rear end ratio are very important as well as cylinder number. The TCU uses this to calculate vehicle speed. If any of these are off, it can keep you from getting it just right.
SY2455 said::hijack: George, Does the 4L-80E have a type of switch pitch TC or is the switch you talk about the Tow Mode on a stock trans? Now back to our reg schedule posting.
George Blake said:TPS settings determine pressure vs throttle position. You didn't like the Grandma shifts, so I sent you one that took care of that. If you want really aggressive shifts, flip that switch I told you about.
Tire diameter and rear end ratio are very important as well as cylinder number. The TCU uses this to calculate vehicle speed. If any of these are off, it can keep you from getting it just right.
It's NOT gonna have a 700r 1-2 shift. That shift is what causes a lot of problems for the 700 and it's due to the drastic ratio change. The 80e won't do that. Just a nice firm crisp shift and your gone.