Almost 90MPH in 2nd Gear!

[pktwatch]

WOW, today my wife and I along with our youngest son and his wife went for a drive. I stopped and filled up with gas and travling down a good state hwy. I was following a little car going about 45mph. he slowed down to turn and after he made his turn (out in the country with NO traffic) I punched it to the floor. I have added some performance mods like a turbo muffler, HTPP III Power Programer and just this week installed my Taylor Thundervolts. I did thes mods more for extra power when towing our travel trailer, not for speed. Back to the story..........I must have been in 2nd gear when I floored it and it geared down to 1st gear because it felt like a race car! I threw us back in our seats, shifted like a drag car and never shifted again till we were almost at 90 MPH! Is this possible, nearly 90mph in second gear?
I honest to god never thought that the Avalanches had anywhere NEAR this much power! Remember this was with 4 big people,our dog and a full tank of gas, I bet we were close to 7000LBS!

Butch

 

[danlwil]

I haven't pushed mine too hard. I'm too old.... and I can't afford the ticket.

Imagine if it had NOS!

 

[magragc5]

Sounds about unfortunetley right, 2nd gear is VERY long. I've noticed around 85 mph stock. I really wish these gears were spaced a little closer. There has to be a 2500 rpm difference between 1st and 2nd!

Ed

 

[kwinsor]

At WOT, the stock computer is set up to shift from 2nd at 72MPH in normal settings, 80mph in tow/haul. I don't know how much the HPIII adds.

kw

 

[Blueruck]

I will take my AV up to 70mph max in 2nd - it is screaming enough at that time.

 

[11H]

Z66 Butch,,,

It depends on what you used for your MPH "add" on the 1-2 and 2-3 shift ... Both push that speed higher than stock ... "almost 90" seems to be close though ... I have a 4x4 with 3.73's and stock tires and I was set conservatively at:

1-2 = +1
2-3 = + 6

Rev limiter = 6,000

It shifted at around 5800 RPM ...

As long as you're shifting at or about 5900 and no more that would be fine ... (I noticed actually holding 2nd to 5900 vs. 5800 slowed the truck down and that's why I run +6 on the 2-3 shift instead of higher ... )

The 1500 av really jumps if you smash it at about 30 MPH eh? ... The 4L60E with that 3.06 first gear puts you at a strong RPM on the 2-1 downshift IMO ...

11H

 

[bekind]

Just to reiterate 11H's comments about the truck jumping, I was driving a country road doing a little over 30 in a 50 behind a slow poke. Anyway I floored it, the truck shifted into first and on dry pavement it actually chirped the tires. I was very impressed!

~bekind

 

[gthomas]

I've got my rev limiter set to 6100 rpm, and my shifts set to +3, 11, 11. I'm hitting 3rd at about 89 with the tach showing about 6000 rpm. I mainly like the higher setting so that the truck will downshift into second at higher speeds. There isn't an inch of 4 lane road in my county, so I do alot of passing on 2 lane highways. Stock, the truck wouldn't go in second above 67. Now if I'm leisurely passing and someone pulls into my lane up ahead when I'm halfway around someone, I can mash the accelerator and drop another gear. It will downshift into second up to about 78.

With 11H's input above, I may get a bit more conservative, because the truck will downshift into 2nd when climbing steep interstate hills in the upper 70s. When in cruise, I'm not really wanting it to hit second gear going that fast.

 

[11H]

I've got my rev limiter set to 6100 rpm, and my shifts set to +3, 11, 11.

WOW ... IMO, with everything I know about new chevy trucks ... (About half of what I should know... LOL) ... That is MAX MAX MAX settings ... Wouldn't go any higher than that on rev or shifting ...

(IMO ... The av is so heavy and aerodynamically lacking, that up around the top of second it hangs there too long at high rpm for my liking... My 2000 Silverado didn't have 2nd gear "hang time" like the av does ! ...)

11H