4.10 vs 3.55

[Aren Jay]

I know the 4.10 improves acceleration etc... But I was wondering.

If you were to consider a 4.10 in relation to a 3.55 equipt car how much more BHP would the 3.55 car need to compete levelly with a 4.10 fitted Marauder?

ie: How much extra Horsepower is the 4.10 install worth.

(I know it doesn't boost BHP)

[Dragcity]

I think distance needs to be specified for this application. ??

1/8 mi. ?

1/4 mi. ?

1 mile ?

[Paul T. Casey]

It's all over the place. I've roasted some similarly equiped guys with the 4.10's, but I see others posting some pretty good times with the gears (although I haven't personally seen it). It's a bigger diffewrence in the south where a lot of tracks are only 1/8 mile. Got me interested though, I'll take a stroll through the timeslips page today and check.

[Badger]

Torque. The 4.10 gear increases the torque not horsepower. The torque is increased at the expense of slightly higer rpms.
If your blow with a roots type don't bother with the 4.10.
Some of the best 1/4 times are with the 3.55.
For N/A the 4.10 make up for the 32V lack of low end torque.

When I was N/A with the 3.55 I was doing 14.6 1/4 Miles.
I also had the 04 tranny and duel knock sensors which bumped the low end torque by just a little.

[ctrlraven]

I have 4.10 gears waiting to be installed, the question is when? Local drag strip opens up in March so I am going to do two days of 3.55 gear runs take a week off to relax and do the 4.10 install and then do another two days of 4.10 runs.

I'm at 14.2x with 3.55 gears and a few mods but within the last year I've installed some goodies thought I was going to hit 13's ended up running 14.4x-14.8x because of tune issues, now that has been resolved I would be happy with a 13.8x with 3.55 gears. If I can do back to back runs of the same time, if not then 4.10s and maybe Stewart WP and underdrive pulleys will go on by the end of spring.

[Aren Jay]

So it is torque not BHP.

Does a 4.10 upgrade mean you are adding 50 FT-LBs of torque them?

[ImpalaSlayer]

where did 50 come from? :dunno:

[Aren Jay]

316 times by 15% rounded up.

[sailsmen]

Torque. The 4.10 gear increases the torque not horsepower. The torque is increased at the expense of slightly higer rpms.
If your blow with a roots type don't bother with the 4.10.
Some of the best 1/4 times are with the 3.55.
For N/A the 4.10 make up for the 32V lack of low end torque.

When I was N/A with the 3.55 I was doing 14.6 1/4 Miles.
I also had the 04 tranny and duel knock sensors which bumped the low end torque by just a little.

Most of the top Trilogy cars in the Time Slip have 4:10. A Trilogy with 4:56 and 3000 PI had the lowest 60' for a long period of time.

The Tuner who developed the Trilogy put 4:10 in his own Marauder. The record holder trilogy has 4:10.

[Bluerauder]

316 times by 15% rounded up.
Should be a straight ratio of 4.10/3.55 or a 15.4% increase in torque. However, that would be AT THE WHEELS. So, accounting for losses, Stock RWTQ is probably in the 250-254 range .... a 15.4% boost would be closer to 289-294. So about + 39-40 lb-ft RWTQ at peak is my estimate if I did this all right. The difference should be seen in the 60 foot time and the first 330 or so feet of track.

That might be enough to cut 0.3 -0.4 off my crappy 60 foot time. :o

[DOOM]

So are you saying you're going to drop in a set of 4.10's charlie???:D:burnout:

[Paul T. Casey]

I have 4.10 gears waiting to be installed, the question is when? Local drag strip opens up in March so I am going to do two days of 3.55 gear runs take a week off to relax and do the 4.10 install and then do another two days of 4.10 runs.

I'm at 14.2x with 3.55 gears and a few mods but within the last year I've installed some goodies thought I was going to hit 13's ended up running 14.4x-14.8x because of tune issues, now that has been resolved I would be happy with a 13.8x with 3.55 gears. If I can do back to back runs of the same time, if not then 4.10s and maybe Stewart WP and underdrive pulleys will go on by the end of spring.

What are your current mods, if I may ask? Not sure I'm buying an increase in RWTQ. The difference is the 4.10 gear turns faster, thereby turning the axles faster, thereby supposedly increasing take off acceleration. Once proper launch technique is learned, I'd expect much better 60' times, slightly better through the 1/8, and close to the same in the 1/4 with slightly slower top end mph.

[mpearce]

I have 4:10's, and LOVE them.

Since when did gears "add" torque to your dyno number? I thought it was "mechanical advantage" only?

Please correct me if I'm wrong.

-Mat

[Paul T. Casey]

Since when did gears "add" torque to your dyno number? I thought it was "mechanical advantage" only?
-Mat


That's the phrase I was looking for. Too early to think when I posted before.

[Dragcity]

Fellas, think of this in terms of a torque wrench....

Long handle vs. short handle...

Set said wrenches to, say 100 ft lb

Either way, your wrench will apply 100 ft lb of torque to the nut/bolt.....

YOU are going to apply more energy to the short handled wrench (3.55)

And apply less physical energy to the long handled wrench (4.10)

Does that help.?

The original question being, how much extra HP would be needed to overcome the 4.10 advantage over 3.55

For 1/4 mi. I'm GUESSING about 30 HP....????

Hence the old saying "Gears are cheap HP" (not HP at all).

What the he11 do I know...........?

[DOOM]

I have a question for all of you guys that have the 4.10s. I was having a conversation with a buddy of mine and he told me if i went with the 4.10 gear setup that i wouldnt be able to go more than 120mph with them:bs:which made no sense to me at all. So my question is how fast have you guys been able to go with the 4.10 gears? What is the MAXIMUM MPH i should be expecting with them?:burnout:

[ctrlraven]

What are your current mods, if I may ask? Not sure I'm buying an increase in RWTQ. The difference is the 4.10 gear turns faster, thereby turning the axles faster, thereby supposedly increasing take off acceleration. Once proper launch technique is learned, I'd expect much better 60' times, slightly better through the 1/8, and close to the same in the 1/4 with slightly slower top end mph.
As far as performance stuff:

JLT Intake, 90mm SVT Lightning MAFS, PHP Intake Spacer, GM Ignition Coil Connectors, NGK TR60IX (1 Stage Colder Plugs), Ford GT Fuel Pump, 42lb Fuel Injectors, 180 Degree T-Stat, SCT Xcal 2 Custom tune, PI 3500 Stall Torque Converter, 2nd Set Of Cats Removed, Flowmaster Super 40's Series Mufflers, Zack's Control Arms and BFG KDW2 255/55-18 tires, though I will be starting to run BFG 255/50-16 drag radial soon. Once I get my tax refund I think I will be getting the EMP stewart water pump and Steeda pulleys in the middle of March then hit the track again to see the difference.

I agree that it's not increasing any hp or tq, what it's doing is just making the most of what's already there more effective, just like an aftermarket torque converter. Dragcity's torque wrench example is right on the money.

It is all about the launch really, from running my car down the track enough times now I know when I'll have a lacking run just in the first few hundred feet.

[sailsmen]

I have a question for all of you guys that have the 4.10s. I was having a conversation with a buddy of mine and he told me if i went with the 4.10 gear setup that i wouldnt be able to go more than 120mph with them:bs:which made no sense to me at all. So my question is how fast have you guys been able to go with the 4.10 gears? What is the MAXIMUM MPH i should be expecting with them?:burnout:

Others have reported 150mph+. W/ the 4:10 u will approach the DS critical at a lower speed then the stock gears.

[Aren Jay]

I think the Max is 190MPH with 4.10
220 mph with 3.55

not that your going to be able to go that fast.

Your not driving a Phaeton.

[03slickvic]

i had 3.27 stock , went to 4.10's and never looked back!! 4.10's is the way to go, remember you can always run a taller tire to make up for more rpms.

[ts-pa]

I think the Max is 190MPH with 4.10
220 mph with 3.55

not that your going to be able to go that fast.

Your not driving a Phaeton.

This may be true if your looking strictly at RPM's. In the real world, you need to look at horsepower, Cd, Frontal area, tire rolling resistance, wind direction & speed, how much you ate for lunch;), etc.

[Paul T. Casey]

As far as performance stuff:

JLT Intake, 90mm SVT Lightning MAFS, PHP Intake Spacer, GM Ignition Coil Connectors, NGK TR60IX (1 Stage Colder Plugs), Ford GT Fuel Pump, 42lb Fuel Injectors, 180 Degree T-Stat, SCT Xcal 2 Custom tune, PI 3500 Stall Torque Converter, 2nd Set Of Cats Removed, Flowmaster Super 40's Series Mufflers, Zack's Control Arms and BFG KDW2 255/55-18 tires, though I will be starting to run BFG 255/50-16 drag radial soon. Once I get my tax refund I think I will be getting the EMP stewart water pump and Steeda pulleys in the middle of March then hit the track again to see the difference.

I agree that it's not increasing any hp or tq, what it's doing is just making the most of what's already there more effective, just like an aftermarket torque converter. Dragcity's torque wrench example is right on the money.

It is all about the launch really, from running my car down the track enough times now I know when I'll have a lacking run just in the first few hundred feet.

Nice list, bigger fuel pump for MAF and Injector upgrade? The stocks should flow enough, no?

[Paul T. Casey]

Me--> Custom Diablo tune, full Kooks exhaust, u/d's, JLT CAI, Torinodan's spacers and polish, 1 step colder plugs, 180 stat, stock gears, fuel pump, inj's got me to 14.02 @ 99.97 on stock tires. Looking at 90mm MAF, larger exhaust (tailpipes), and converter this spring. Through it all, my 60' times haven't changed much from bone stock. I know gears would help here.

[ctrlraven]

This may be true if your looking strictly at RPM's. In the real world, you need to look at horsepower, Cd, Frontal area, tire rolling resistance, wind direction & speed, how much you ate for lunch;), etc.

Yep that is true, my car did 149mph on the dyno with 3.55 gears and a 255/55-18 tire. It got up to that speed pretty quickly vs. when I have taken it to 140mph on an actual road, totally different.