I went from 3.73's to 3.23's and picked up .14 in the 8th mile. On motor. it even hooked the same 1.78 60ft. and drives alot better and quiter and better on GAS! so my vote will be stay with the 3.23's I must have the 8th fast bolt on car 12.77 well actually I only get to run 8th mile but if you add it up a 8.19 should be dead on 12.77

 

I hate to burst your bubble, Frank, but not everyone in the country was at that event. I'm sorry it's just a little peave of mine when people boast things that aren't true. JL claimed to have the fastest blah, blah, blah, but it simply wasn't true. Anyway your car is impressive so is his and I'm happy for you and there is no need to make false claims.

Now to the gear talk. When selecting gears you can't hold much to what people tell you. You have to do the calculations. I went with 373's because I'm planning some upgrades. If you are going to run more than 113 mph on a 26" tire then you shouldn't run 410's. You don't want to shift into overdrive before you hit the 1/4 mi. Here is a link for a good gear calculation site:

Gear calculation link

 

Well I tried 4.10's ran it at the track and picked up nothing from 3.42's. Slowed down 4 mph in the 1/8th Well I put my 3.42's back in and will probably never go lower. I am contemlating 3.73's but i don't think it will enough to be worth it. Besides my car 60's 1.5's on N2o with 3.42's It was something I wanted to try and was not happy at all with. JMO experiences. Later Clint

 

Some of you guys must be just putting gears in and NOT reprogramming the PCM. That is the only thing I can think of that would explain some of the things I'm hearing. I went from 323's to 373's, REPROGRAMMED the PCM, and went 3 tenths faster in the 1/4 mi. You ALL should get similar results. I used a hypertech to make the change but LT1 edit would prolly be a better purchase than the Hypertech NO POWER programmer.

 

I used a Power programmer too. my car just likes the 3.23's better

 

I gained maybe squat with my gear change from 3.23's to 3.73's. My combo made a lot of rwtq, 450 on a chasis dyno and that combo did not need gear.

Now my new mill will be much more aggresive in the higher rpm's and the gear will actually for the first time in years benefit me.

 

I have 4.10 in my m6, and like it quite a bit, but I think if I had an automatic, 3.73 is as low as I would go. Sometimes even with the M6 I wish I had 3.73s, and that is with a .5 overdrive. If you drive your car everyday, or close to it, do yourself a favor and get the 3.73, your wallet and motor will thank you.

 

Did you also add mph to the shift points? I went +6mph (max) on all shift points because I'm now making some power in the higher RPM's. My car is shifting at around 62-6300 according to the tach but in reality it's prolly more like 6000 at the shift points.

 

I would get the car dynoed to see where you really make power at.

 

Good advice. I used back to back runs at the track which can work also, assuming you get traction. What ever you do, Never rely on your Butt-O-Meter. LOL!!

 

(Note: MUCH heavier car here!)

I went from the stock 3.08 gears (impy SS) to 3.73s. I have recently been running 25" tall rear tires and it isn't too bad. That puts the rear gearing equal to 4.03 or somthing with stock height tires. I'm now putting in 4.10 gears, but I'll also be going with taller tires (either 27 or 28") to offset it on the road.

AT the track with 26x10.5 ET Streets, my best MPH is 98.42 through the quarter with only bolt-ons shifting around 5500. THat was when it was much cooler outside. Through the summer my MPH will be lower, so I doubt I'll shift into OD at the track for a while (until I spray it.) WHen I put the bigger cam in it, it'll move my redline up considerably and still put me through the traps in 3rd on motor.

Howevre, my 4300# car needs a little more gear to kepe up with ou lightweight F-bodies and the even lighter weight F0x bodies

 

I actully had to back off on the mph or it wont shift. right -1 mph 1-2 -1mph 2-3 And it is shifting at 5800 now. with 1.6 RR and stock springs I dont want to go higher.

 

Hey if it works for frank or anybody else good for them.

 

It won't shift? Did you raise the rev limit? Mine is set for 6300 RPM with the stock valvetrain. I'm getting very good results.

 

I hope this dont getinto a stealing thread kinda deal. but I have the pcm rev. limitter maxed out and the MSD set at 6400 this is just what works for me.. I also had 2.73's in my 91 camaro in sig and put in 3.73 and picked up nothing. I can only speak for my car and what gains and losses I have had with it. I have a freind who has a M6 and went with 3.73 from 3.42 and his car ran the same as it did on street tires (he was running DR)He might of picked up just a hair. then the rear broke on him.