ok so i have decided to put in a set of 3.73 gears in my recently purchased 1998 z28 a4. i was told that it would give me the most bang for the buck at this stage of modifying my car (i currently only have intake and exhaust mods). just a few questions before i order them... any help would be appreciated

1.) do you feel this will give me the most improvement in acceleration for my daily driver (other than nos obviously)

2.) does anyone have an idea what kind of gas mileage drop i will experience? (i currently have 2.73 gears)

3.) i am assuming i will have to either have someone professionally tune my car or buy a programmer to fix my speedometer... is this correct, and if so is it the only thing i will need to have adjusted

4.) what brand for gears and what specs. i was told: richmond series 2/ 7.5 inch gm 10 bolt with the full installation kit. i plan to purchase these from summitracing.com

once again thanks to anyone who can offer any help!!!

 

Try the search function for help, these topics have been covered 100x...

1. yes it is a nice bang for the buck...p.s. it is nitrous not nos unless you are referring to the specific brand Nitrous Oxide Systems

2. depends on how much highway driving you do. even so....a little...good outweighs the bad imho

3. yes it is correct, yes the speedometer needs to be fixed

4. gears will depend on what your car came with...if you have 2.73s you need gears for a 2 series carrier...if you have 3.23s you need gears for a 3 series carrier, and a master install kit

 

appreciate the help! thanks much... do you have any idea what kind of difference i can expect going from 2.73 to 3.73 in an 8th mile or from between 30-50 mph rolls?

 

Sorry I can't tell you that, I have a M6 and not an A4. With an M6 thought I saw a huge gain from 3.42 to 4.10, three tenths in the 1/8th.

 

And don't go with Richmond Gears unless you like a lot of gear noise - they are notorious for that - has to do with the way the gears are cut. Go with either Motive or Genuine GM gears.

 

From what i have read if you like to drag your car alot you might want to look into 3.89 gears for an auto especially if you have 1/8 mile tracks instead of 1/4 .