i needed to make a choice last week, either to go with a 3.73, or a 4.10 in my moser 12 bolt that i am getting installed wed @ speed inc. i just got my nitrous installed this winter, so i have yet to run it with nitrous. i talked to larry from speed inc. and he told me 99% of the people that order new rear ends get a 4.10 (M6 owners i mean). i told him that i want to spray, and that it might just be too much off the line. and he told me that well how often do you go to the track, which i will probably only go like 4 times this summer. so i will be doing a lot of street racing, and also a lot of N/A runs. so that is what convinced me into getting a 4.10. get a 3.73 for a lot of track use and N20, get a 4.10 for N/A use.

Also i have some questions that i need answered:
(i will list my mods bellow, so u can see my setup and how much power i have)

1. How bad will i spin if i spray in first with a 4.10 gear (i am only using my 75shot but want to do 100shot)?
2. Should I wait until second gear to start spraying?
3. Am i always going to have to manually hit the arming switch when i hit second gear (my setup is a WOT switch) i mean that will be hard to do, shift from first to second and then flip a switch fast or do they make something that it wont spray until second gear, ive heard something about a mallory switch or something but dont really know much about it?
4. What RPM to drop it in at?
5 What gear will i finish in both N/A and with NO2, and how far into the gear will i finish it in?
1998 Trans Am WS.6 M6
Lid, Borla, Mac Headers w/ offroad y-pipe (02 sims), SLP air temp module !CAGS, descreened MAF, ported MAF, MAFT, MSD window switch, NX wet (75shot),NX bottle heater, MSD spark plug wires, NGK TR6 plugs,BMR SFC's, BMR LCA's, Z06 clutch, 315 NITTO drag radials

 

im stuck in the same situation

i think i will go with 4.10s .. and worst comes to worst, just wont spray in 1st gear ... though i will be running on ET drags or Hoosier QTPs ... also, i might step upto a 28" tire for track use so that would bring down my gearing a bit ... i think a 4.10 on 28" tiers is like having 3.90 on 26" tires

i'll be running on 315 nittos on the street so the 4.10s should be a lot of fun (ps, ud want to rev high if ug et 4.10s, i dont know where ur rev limiter is for that LS1 of urs .. but i rev to 7k so the 4.10s should be fun, if u got a stock cam u will find that ur car runs out of breath too quickly with 4.10 gears)

 

what do you mean runs out of breath??

 

Speed inc= Thumbs up

 

well with 4.10s, u will rev up real quick, but a stock cam / stock rev limiter wont allow u to rev past 5800 ... so u gotta shift too quick ..

for example ... say at 70 mph in 3rd gear u might run out of "breath" but if u have a huge cam / edited rev limiter .. u can rev higher and wont have to shift into 4th so quick

 

Get the 4.10's. When I was a bolt on car with N2O I ran 4.10's in the stock 10 bolt with 26" Hoosier QTP's. With a 100 shot I ran a best of 11.88 @ 113 MPH. That was running through the top end about 6000 RPM in 4th.