3.73 or 3.91 gears

[blkngldbabe]

Hey all. I've been seriously considering the change up in gears. More giddyup off the line and a fairly inexpensive zip provider since I can't afford FI currently. My concern is the tune. Is it necessary and how hard is it to deal with since we have that lovely programming nightmare in our beasts? I drive Barossa year round so I'm not sure which gear I should go with. I'm not concerned about top end loss as I'll never hit it TBH. Gas mileage is a bit of a concern but really, I'm not that bothered since I get pretty good mileage currently IMHO. Any thoughts on this? ANyone have either set ups?

[lscamaro]

Are you an auto or manual?

[IneedAZ]

Before last week if u were to ask me i would say go 3.73, but i just swapped my 3.73 for 3.91 and i like it. Car feels better, stays closer to the power band. I am at 2000rpm at 65 and 2500 at 80.

[blkngldbabe]

I'm a manual. Did you need a tune to deal with the speedo?

[RubyCamaro]

[IneedAZ]

Originally Posted by blkngldbabe

I'm a manual. Did you need a tune to deal with the speedo?

Yes, without the tune u will be 10-15mph off depending how fast u are going. Matt at FSP did a good job getting me within 1mph at all speeds yesterday.

Also, you are lucky u dont have the big expensive of a complete rear swap.

[Apex Motorsports]

You will need tuning. Swapping to 3.73 will result was an equivalent torque gain of approximately 15% or 41 lb.-ft. of torque and will raise 70 MPH cruising RPM from right at 2000 to just under 2300. Going to 3.91 will get you in the neighborhood of a 20% torque gain and put you over 2400 RPM at 70 MPH.

[blkngldbabe]

Thanks for all the info. I'm afraid I may have issues getting the tune up here in Canada though.

[lscamaro]

Originally Posted by blkngldbabe

I'm a manual. Did you need a tune to deal with the speedo?

Yes, you'll need a tune to adjust the speedo.

Originally Posted by IneedAZ

Yes, without the tune u will be 10-15mph off depending how fast u are going. Matt at FSP did a good job getting me within 1mph at all speeds yesterday.

Also, you are lucky u dont have the big expensive of a complete rear swap.

If you're going to do it, I'd do the 3.91. They're gm products and I believe less expensive too. The only problem is that you'd need a tune. I don't know if ipf adjusts for gears and I just wouldn't do a trifecta tune

[blkngldbabe]

I'm definitely favoring the 3.91's due to the sweet pricing but since I drive in the snow, will the extra torque be a severe issue? I usually start off in 2nd gear when it's slippery anyways and have only been stuck once (2 foot dump of snow and the road hadn't been cleared at all yet) in three years. I also need a tune for it and don't know if I can get IPF to hook me up, up here. Anyone have any thoughts?

[RS111341]

Hypertech has a speedo calibrator that'll fix your speedometer and Autoanything sells them pretty cheap

[right to travel]

3.91 wont void warranty with tune and install from gm dealer

[blkngldbabe]

IS there a GM tune to work with it since it's a factory gear? That would rock

[right to travel]

yes. see your dealer if they are not tards. if they are find another one. the gm performance mag for the month just dropped and lists a bunch of stuff to add on that wont void ur warranty if done at the dealer.