I need some good advice on what type of gears would be best suited for my setup. The car is a H/C LS2 shortblock. My current goal is to get the car into the 10s N/A and then hit it with a 150 shot. I'm running an SS4000 converter and built 60E and currently building a 8.8 rear for it. I bought 3.73s thinking it would be a decent increase from the 3.23s but I also want to step up to a 28" tire for when I start spraying the car. Will the tall tire kill my gearing a lot on motor? I trapped 121mph last year and was hoping to gain a few extra to hit 10s. The car does see a lot of street duty as well. Will stepping up to 4.10s make it a pain to daily if I choose to do so? I think either gear will give me enough mph to work with on the spray but I want good n/a performance as well. My other option is keep the 3.73s and run a 26" radial on motor and the 28" on spray. What do you guys think?

 

4.10's with the 28" tire will make is like 3.73's on a 26" tire id go 4.10s and the 28

 

Hey man, how's it going
Make sure to consider if you have enough gear to stay out of 4th gear for your spray runs. The 4000 stall plus spray will get you thru the gears pretty quick I'd think.
I'm not 100% sure what the best combo is for you, but there's some pretty smart cookies around here to help ya. I'd guess though that a 3.73's with a 27 or 28" tire would help keep you from running out of gear. 3.73.s are always nice when you're back on street tires too.

 

I do agree with you because I drive the car on the street too and I will most likely be running a 26" tire then because 28" street tires are damn goofy looking. If they made a 3.90 for 8.8s I think that would be my best bet. I'm not even sure where they car would trap on the spray.

 

You have the Ford 8.8 right? They do make 3.90s for those rears. Out of the options you stated it all depends on what kind of track tires you get. If you go with 26" slicks get the 3.73s, if 28" slicks get the 4.10s. What are you revving the motor to? I think you might still run out of gear. If it was my car I would go with 3.90s and a 28."

 

i had a camaro that would trap about 121 mph N/A and on the 150 shot it trapped right under 132 mph with the 275/60/15 MT (which are just short of 26") and 3.42 gears at about 6800 RPM or so.

dicky

 

28 inches. 27.99 to be more precise.

 

They do offer 3.89 and 3.90 gears for the 8.8 rears

3.89
http://www.summitracing.com/parts/RMG-69-0311-1/

3.90
http://www.summitracing.com/parts/MGR-F888390/

 

I would stick with the 3.73's... that is what I had and ran a 26" tire when I was motor only, then when I started spraying the car, I went to a 28" tire...

 

^Agree, keep the 3.73s, especially since you're gonna step up the tire size when spraying. It'll run good on motor and spray = best of both worlds.

 

sorry i meant the 275/50/15s, thanks for pointing that out

 

No problems I figured you did by looking at the MPH/RPM you posted. You were revving that thing out

I like the 3.90s with your setup because with 28"s they'll give you the gear you need with a bit more "win" than the 3.73s.

 

I rev the car to 6700 now and could go higher if needed but its not making any more power up there through the LS6 intake. Is it going to be possible to go 3.90 and run a 28" tire for both N/A and N20 runs? Thats really what I'd like to accomplish as opposed to having 2 sets of wheels with drag radials and swapping them at the track all the time.

 

As long as you don't spray above around 175, you will be okay...

 

I won't be doing that unless I'm a tenth away from 9s lol stock shortblock here.

 

I have 3:90's with a 28" tire and a 150 shot and I am running out of gear before the traps. My car shifts at 6600 and my limiter is at 6800. My nitrous shuts off at 6400 and I am hitting the limiter before I cross the line. Not quit sure how others are doing it, but if I were you I would deff go with a 3:73.

 

hmmm thats probably all I need to hear, what mph are you trapping? Others may be going faster if they run on bias ply tires as they grow on the big end, radials won't.