Power drops in 6th gear…top speed governed?
 

I'm already loving this forum…you guys rock! Just bought my 1LE in Oklahoma and driving it back to San Diego. I've been at some pretty high elevation for a lot of the trip (been through Taos NM and took the high road to the Grand Canyon and then down to Sedoan AZ). Yesterday on my way to the Grand Canyon I was on some incredibly killer roads and ran the car pretty hard. Kept her at 120 mph for about 30 minutes straight…no kidding. What I've noticed is that from 120 + acceleration is slow especially in 6th gear. I was able to hit 135 at one point but it felt like it took forever to get there. I've heard these cars have a top speed of 155 mph but I'm not seeing it. Felt like a pig at anything over 120.

When I had the rpm's high in 5th it still pulled pretty strong but as soon as I drop her into 6th…..sluggishhhhhhhhh.

Everything is still stock…I'm thinking a aftermarket intake might help?

.... 6th gear loses power and the ability to accelerate. its supposed to be that way. 5th is your top speed gear

so that is how it is designed? 6th gear is nothing more than a gas saving gear….no other use. You are saying that if I want to hit the car's top speed I need to do it in 5th. Just to be clear, I have the 1LE trans…m6060 or something like that.

"I wanna go fast, I wanna go fast, I wanna go fast"

- Ricky Bobby

6th gear is for cruising at highway speed. Just an overdrive gear. You'll notice that there is a significant drop in RPM from 5th to 6th. Shouldn't be using anything higher than 5th to haul ass, lol.

First manual trans car? Higher rpm = more power. Especially needed at higher speeds. 6th is geared to be a cruising gear. If you want speed run out all the gears....

6th gear is pretty much the final drive of the 3:91 gear ratio. In turn it's basically a cruise gear not going to get much power output from that gear. I've pulled 120+ in fourth gear and it still gives me more. Not sure how these motors are built but you're asking for problems trying to pull those high numbers from that gear. Hence burning up a cylinder prob #8 since it's the furthest away from the the circulation of coolant.


If you're reading this objects In side view mirrors are losing as I'm rowing the 3:91's

This may help in understanding what is going on. Both 5th and 6th are overdrive gears, 6th more so than 5th however.

MM6 w/ 3.91
1st gear ratio: 2.66 10.42
2nd gear ratio: 1.78 6.97
3rd gear ratio: 1.30 5.09
4th gear ratio: 1.00 3.91
5th gear ratio: 0.74 2.90
6th gear ratio: 0.50 1.96

I could never afford a supercharger,but if one were installed,then would she pull in 6th?

In a sense, yes. GM is required to meet agreed-upon CAFE targets, and six-speeds with very high sixth gears is part of how they do it. That gear is unrelated to wringing excitement out of the car.

4th gear will get you to 130. When I dyno mine in 4th that's what it hits before reaching rev limiter.

If you only hit 135 you were NOT at high rpm's in 5th, or your shits just broken. From a gear perspective 5th could do 180-190 or so assuming you had the hp and aerodynamics to allow for it.

FYI....driving at 120 for 30 minutes is retarded. Even I push the limits a bit but that's bitch slapping fate in the face and asking for trouble Next time you'll end up with a huge ticket and no license or a reck. You basically bet there wasn't a cop within 60 miles...stupid!

These cars have no problem pulling up to that 155 limiter. 4th gear I've hit 132 and hit the rev limiter/fuel cut. 5th still pulls over that.

Whens the last time you drove open roads (not interstate) out west? You may drive 60 miles and not see another car, much less a cop. That said, personally I do most of my really high speed driving on the track.

4th will hit 155 on an regular SS, I've seen it on the dyno, mine hits about 152 in 4th