3.55 or 3.73

[98gtblue]

i have a 98 gt 5 speed with Lt headers,o/r h pipe,flows, 70mm tb, cai, pullies, and short shifter......should i go with 3.55 gear or 3.73. still have to drive on highway to work everyday. also friend is selling me his 3.73 for $80 but 3.55 dont need to be recalibrated. which gear should i choose? thanks
also what rpm at 70mph on 3.73?

 

[mogs01gt]

3.73

 

[Graham052]

3.73 without a doubt, sorry I cant remember rpm's of the top of my head

 

[NasaGT]

3.73. Prepare for a bunch of people saying 4.10 even though you didn't list it as an option.

 

[true blue blood]

Not to sound stupid but Are those gears from your friend used? If so don't use them. Yeah everyone is gonna say 4.10's and thats what I would say, depending on how much highway driving you do would be the deciding factor but definetly do the 3.73's if 4.10's aren't for you, 3.55's just don't cut it!

 

[GTvert01]

definitely 3.73 over the 3.55s, the calibration is just a speedo gear for the 98s takes about 2 minutes to change and costs about $10.

 

[mrvax]

definitely 3.73 over the 3.55s, the calibration is just a speedo gear for the 98s takes about 2 minutes to change and costs about $10.

3.73s for sure. 2300rpms in 5th at 70.
Do not swap your speedo gear. Keep the stock one in there and buy a Dallas Speedcal. The speedo gear will still be off about 10% and it will get chewed up and fail within a few months. I hold the world record for longest speedo gear swap before failure. 13months and 13,000 miles.

 

[Slapyo]

i would say go for the 3.73s.

 

[Camshaft213]

3.73s, but i STRONGLY urge you to get 4.10s

 

[GinoGT]

I guess I'll be the one to demand 4.10's and then go on telling you that anything less is . I don't want to see anyone go with anything less unless they have a supercharger sitting in their garage, none of that "power adder in the future" crap.

 

[Dallasgt01]

i would use 3.73's i have 3.55 and like them but i drive to much highway for the 4.10 so my next upgrade is 3.73

 

[NitroDuck]

if you swap the gearset you'll need to recalibrate, no matter what. also, i wouldn't put in used gears, they'll most likely be noisier, and you can get new frpp gears extremely cheap from gef.

truthfully i'd go with 3.73s bare minimum. 4.10s are where its at, though you operate in a lower powerband with NPI heads.

 

[GTvert01]

DallasGT,are you talking about the GT or the cobra? I have a 01 GT convertible and still get around 26 hwy mpg with 4.10s

 

[StangJonGT]

3.73s, no doubt.

 

[KJ Hoppus]

3.73s