Gear Discussion - Timeslip Comparo 2 trucks

[Azmotorhead]

1Fast400 I'm with you on this.
Someone stated it earlier
The rear ratio is a multiplication 4.56:1 is a greater multiplier than 4.10:1.
Lets take it to extremes
say you put in a 2.73:1 ratio vs a 4.56:1
The higher numeric ratio multiplies torque quicker than thew numerically lower.
Take a Nascar Stock car for example on a short track they will run a 4.88:1 gear set to get them to the top end faster,look how much wheelspin they get leaving the pits. Now on a Superspeedway they'll run a 3.08:1 or so enabling a higher speed on a longer strech. hardly any of those cars had wheelspin while leaving the pits+ the crews were pushing the car more on exit to "help" the car get rolling

 

[ViperTruck2933]

1Fast400 I'm with you on this.
Someone stated it earlier
The rear ratio is a multiplication 4.56:1 is a greater multiplier than 4.10:1.
Lets take it to extremes
say you put in a 2.73:1 ratio vs a 4.56:1
The higher numeric ratio multiplies torque quicker than thew numerically lower.
Take a Nascar Stock car for example on a short track they will run a 4.88:1 gear set to get them to the top end faster,look how much wheelspin they get leaving the pits. Now on a Superspeedway they'll run a 3.08:1 or so enabling a higher speed on a longer strech. hardly any of those cars had wheelspin while leaving the pits+ the crews were pushing the car more on exit to "help" the car get rolling

Your analogy would support my theory that the 4.10s would perform better on the top end of the track.

 

[blown srt10]

456 gears are the right gears for your truck ive had both and just because you have the same trucks with same mods dont mean there going to run alike me and my cousin both had 99 ss camaros 6 speeds and mine went 13.01 and his ran 13.30 and we even drove each others car and ran close to the same thing

 

[Azmotorhead]

4.56's will pull harder out of the hole but you'll reach peak RPM sooner.
4.10's will give your truck "longer legs" your top speed will be higher -on a longer run-
You were about a tenth behind him the whole race but see how your MPH is greater than his.
If given another 1/4 to 1/2 mile you would be even with him & passing(maybe)

DC switched to 4.56's in 05 for a reason:idea: same with 05's getting better front calipers:idea:

If youre breaking traction with the 4.10's (suffering 60ft's) 4.56 will make it worse.

Exactly Viper,that is what I was trying to say in my first reply

 

[droptail]

456's will outpull 410's. If the 410 truck is "pulling" side by side (no shifting) then look somewhere other than gears for the advantage.
Lower gears allow more driver control, and are more predictable, than taller (numerically smaller) ones.
Once the tire breaks loose, the engine revs up a little, and with taller gears the wheel spins fast, too fast to control effectively.

Shorter gears muscle the tire rather than leverage it. With shorter gears, the tires are more directly connected to engine rpm, allowing to modulate a burnout more directly with engine speed. Taller gears allow the tire to spin (out of control) faster, for any giver rpm, which takes more time to slow it down and re-hook up.
Take it to its limit, 1:1 wheel turns same as engine, wheel is easily contolled with rpm. 5:1 wheel to engine tall gearing, that tire will orbit out of control when adhesion is lost before you have a chance to get off the gas. Make sense?

 

[ViperTruck2933]

456's will outpull 410's. If the 410 truck is "pulling" side by side (no shifting) then look somewhere other than gears for the advantage.
Lower gears allow more driver control, and are more predictable, than taller (numerically smaller) ones.
Once the tire breaks loose, the engine revs up a little, and with taller gears the wheel spins fast, too fast to control effectively.

Shorter gears muscle the tire rather than leverage it. With shorter gears, the tires are more directly connected to engine rpm, allowing to modulate a burnout more directly with engine speed. Taller gears allow the tire to spin (out of control) faster, for any giver rpm, which takes more time to slow it down and re-hook up.
Take it to its limit, 1:1 wheel turns same as engine, wheel is easily contolled with rpm. 5:1 wheel to engine tall gearing, that tire will orbit out of control when adhesion is lost before you have a chance to get off the gas. Make sense?

Kind of makes sense but not really.

First of all neither truck had ANY tire spin so the whole spinning out of control concept is not applicable here. :dontknow:

My 4.10 truck definitely out pulled the 4.56 on the top half of the track too. :dontknow:

Good thoughts but they don't seem to be proven based on our side by side race. :dontknow:

 

[mmmmtorque]

Kind of makes sense but not really.

First of all neither truck had ANY tire spin so the whole spinning out of control concept is not applicable here. :dontknow:

My 4.10 truck definitely out pulled the 4.56 on the top half of the track too. :dontknow:

Good thoughts but they don't seem to be proven based on our side by side race. :dontknow:

I would take both trucks to a local dyno (on the same day) and compare numbers (and curves). Would bet your truck is laying down more ft lbs and perhaps more hp than him.

I have done the exact same mods to two different trucks and seen 15-20 hp and 30ft lb difference in motors. (done on the same dyno with the same tune).

 

[ViperTruck2933]

I would take both trucks to a local dyno (on the same day) and compare numbers (and curves). Would bet your truck is laying down more ft lbs and perhaps more hp than him.

I have done the exact same mods to two different trucks and seen 15-20 hp and 30ft lb difference in motors. (done on the same dyno with the same tune).

Good point. We are going to do that.
Boomer's dyno is unavailable for a couple of weeks. Once it's up and running we are taking both trucks out there.

 

[UNIBOY]

Okay, Lets talk about 4.10s vs 4.56 gears. My neighbor and I went to the track last night. I only got to do 1 run but we lined up his 05 and my 04. Here's how it broke down.

His 05....X-Metal Stage II PCM, Bassani Headers, X-Metal Catless mids, JMB Custom CAI, Magnaflow, Gen IV shifter...stock 4.56 gears.

My 04....DC Stage II PCM, Belanger Headers, Highflow cats, JMB Custom CAI, Magnaflow, OEM shifter....Stock 4.10 gears.

First run in a while, I really babied it out of the hole, launched at only 1500-1600 rpms.

05 RC
R/T .117
60' 2.181
330 5.763
1/8 8.654
MPH 85.20
1000 11.161
1/4 13.276
MPH 106.71

04 RC
R/T .046
60' 2.213
330 5.819
1/8 8.773
MPH 83.63
1000 11.276
1/4 13.381
MPH 107.11

Discussion: Are the 4.56s really an advantage? Granted his low end is better than mine BUT I ran him down with the mph at the other end of the track. My launch was intentionally very soft. I usually cut a 2.1 or better 60' and usually run 13.0x@108mph. He did several runs last night and this was his best run. I'm trying to figure out if the gear change is really worth it.:dontknow:


I left after the first run because it rained and my son was with me (couldn't stay late).

I am assuming you were in 4th at the traps on this run?

 

[ViperTruck2933]

I am assuming you were in 4th at the traps on this run?

Yes both in 4th gear. I was pulling him in 4th gear. A little more track and I'd have passed him.

 

[UNIBOY]

Yes both in 4th gear. I was pulling him in 4th gear. A little more track and I'd have passed him.

But you didn't. Now were even. lol