I have run both on my auto, currently running 4:10's. The 3:73's IMO are better for a regular street car, the 4:10's are a little raw, 60mph is 2250 on my car with 27" tires. Don't buy the Jegs brand, they whine alot (I have the jegs 4:10's)

 

Well it all depends on how far you are going to take your 6'er. If you are going to stay N/A i would say go with the 4.10's andlsd, traction wont be a big prob and you will feel a big difference off the line. But if you are going F/I i would say go with the 3.73's and lsd because traction will prob become a factor with 4.10's and a blower.

 

The stock 215/65r16's are 27" tall.
the Stock tires on the 17" rims are 27" tall as well.
So going up to a 29" tire is definitely going to take some of the effective gear out.
I'm probably going with 4.10's and keeping the 29" tall rear tires.
They look badass and will definitely help me hook up.

 

The taller tires will reduce the effective ratio-yes,
BUT- You now have 29" tires with 3.31's so moving to a 3.73 will be felt. The performance should still be better, worst case it would be the same, as stock tires/gear combo.
I vote for 3.73 for a DD car on hwy/open roads a good bit off the time. 4.10 are too high for criusing in my opinion.
If you are concerned with hook-up a T-Lok would be benefical. The RPM's are not going to be low with that OD ratio and 3.73, even higher 4.10's.Then if you switch back to a smaller daimeter tire then what? In the long run you will bepleased with the 3.73's, I think

 

I've got a blower, T-lock, manual, and 410's; no problem. I cruise at 70mph @ 2700prm, no big deal. Now if you are maunal and it's a DD in heavy stop and go traffic the gears are the least of your problems; it's the manual trans that will give you grief. My car only gets driven 2 or 3 times a week so the trans is no biggie and I wouldn't have it any other way.

 

Thanks for replying.
I was hoping that someone with an X-charger would chime in about 4.10's.
I was really worried about down the road when I get an x-charger if I'd have to swap back down to 3.73's.
I guess not. If it is fine with a manual tranny, then an Auto with OD should be fine.
Thanks again..
BTW..
What size tire are you running? And how is the traction?

 

Your gear whine is more than likely due to the pinion in relaiont to the ring gear. How much gear lash did you have when you put them in? .010" is ideal, also it could be preload on your pinion bearings. It should take 12 ft./lbs to turn the yoke.