owero01

With my 4:10s, I get around 25 on the highway at 70 mph.

PROMETHEUS PRIME

Gas mileage versus throw you back in your seat.
The pull from the line out wieghs the 1 mileage loss to me.

rravolt

yes it definately out weighs the loss in mpg by a thousand

ohsixgt1217

The cai/tune prolly gave him 20 or so, maybe 25 as you said.

Unless he is some kind of f/i or nitrous the headers wont give give more than 8-10 rwhp. F/I will give him 20.

EDIT: Headers probably 5-8 hp because of the catted X, o/r X usually gives 8-10

hecktic33gt

Thanks a lot guys

blueherd02gt

The faster you are the worse gas mileage will be....

sleeper2

Iwent from 3.31 to 4.10 on mymanual GT, and my city mpg went UP by 3. I'm giving a lot less throttle to keep the rpm's up after shifting. This overshadowsthe 1to 2 mpg decrease on the highway.I'm not sure if this crosses over to the auto tranny, though.

Sleeper2

Orion_240

I hear lots of praise for the 4.10's but often it's coming from folks with manual. I've only seen the 3.73's being installed on automatics and would stick with those.
Anyone with an automatic and 4.10's?

thewarmachine

I have the 3.31 also, and was considering switching to 4.10. Glad to hear it helpscity mpg's.

DeStonn

Never understood the 'gas mileage' worry. If I was worried about the gas mileage I wold have bought a hybrid. JMO