Hey guys I want to get everyone's opinion on this one. I have a '69 RR that I am currently restoring and I am trying to decide what gear ratio to use in the rear end (currently a 3.23). I want to be able to use it on the street for cruising, but want to be able to light up the tires when I feel the need. The obvious choices are 3.55, 3.73, or 3.91 for the set up but I have only driven a 3.91 other than my 3.23. I am afraid a 3.91 might be too low and give me too high of rpm's with whining going down the highway. SO I am thinking that narrows it down to 3.55 or 3.73. Any opinions on which is better or is there even a noticeable difference between the two? Thanks for helping out!!

Whats wrong with the 3:23? I had that in my cuda and
it would light the tires up just fine plus would top
it out at around 140 MPH.

I have a 2:76 in my dart thats a 4 speed that roasts the tires off. Sell me your 3:23 if you don't like it.

3.55.

roadrunners where light to light terrors.. NOT hiway cruizers.. so stick some 4.30's in there.

Again,

I'll take the 3:23's off your hands.

I'm gonna go against the grain here. I run 3.91's in my Satellite, and love them. But, My car is used around town only. It rarely sees freeway miles, and when it does, I'll admit its not exactly the hot ticket! If you do any freeway miles, I'd go with 3.73's, just so you can peek at 60 MPH below 3g. If its just a Saturday Night Special, and you're in it for the fun factor.....3.91's are fun. Heck... 4:10's!!!

I have a 2.76 in my 318 cuda and it will lite em up real good. It is great on the highway unless I plan to break a speed limit at all, then I wish I had even higher. I would use the 3.23 or higher for cruising and especially considering MPG these days.

8-3/4 is a pretty quick swap, enough practice and you can change gears in 20 min. I have 3.91 in my runner and like it, but change to 2.76 for the highway. If I had 4.88 I would probably use that for bursts about town. I do like 3.55 as an all around gear.

Also depends on what size tires you have in the rear. I like my 3:55's with a 28" tire. With a 28" tire I also would not be afraid of cruising the highway with 3:73's either. I had 3:91's for a couple years and it was fun, but the highway was a bit much for trips over 1.5 hours. I'm not a sissy, but the rpm's and noise get annoying.

depends on how much highway driving you are going to do. What are the engine specs..and on and on. 3.91's are a good gear for a b-body. With a set of 275/60/15's you can cruise at 70 no problem. 3.55's are ok but they are dog gears compared to 3.91's...as are 3.23's. Try the 3.73's they are pretty new to mopars. Let us know how they run.

i drove with 4.30's on the hiway with a 28" tall tire at 60-65mph.. wasn't all that bad.

yeah 3.91's and even 4.10's aren't THAT big of a deal. I often drove 50+ miles one way to race w/ 3.91's and 4.10's. When you build one of these cars MPGs should be the last thing on your mind. Choose the gear that will BEST work with you set-up.

With a short tire (something less than 27-28") I would take the 3.55. 28 and above, I would opt for the 3.73.
But this is a question of preference, there really is no right or wrong answer.

Not to high jack but would a swap to a 3.73 or 3.91 from a 3.23 be noticable and how much will it affect the top end?

3.55 (or 3.54 in danas) are the best all around ratio for a street driven Mopar. Especially with the price of fuel. Any lower (higher numerically) is just crazy.

355's in my 69 roadrunner is just right

Again, I would love a 3:23 in a 742 if anyone wants to part with one.