4.10's Too Short...

**Wesman** · 02-23-2010, 07:59 AM

My car is an M6 with 4.10 gears. Its had the 4.10's since I bought it 3 years ago, so I've never known any different.

I put the car away for the winter and haven't driven it in about 2 months. In the meantime, I picked up a new daily driver, a '08 Cobalt SS T/C. Fun car.

Anyway, I took the T/A out yesterday to blow the dust off, and I realized how extremely short my gearing is with 4.10's. I mean I knew it was short before, but after driving the Cobalt for 2 months, I realized that I actually have taller gears in my 4 cylinder Cobalt than I do in my T/A. There is something wrong with that picture, especially since the T/A has twice the cylinders and 140ft/lbs more torque. Its just not necessary. And its not like my 1/4 mile times are that great, I end up spinning the entire way through 2nd gear.

Maybe its just me, but the gears are obnoxiously short. I take off from a stop, and by the time the car is moving, time to shift to 2nd. Then immediately 3rd, 4th, and I'm in 6th by 40MPH. I'm running 26" tires on 18" rims BTW, which is about the same as stock.

I've decided I'm going back to 3.42's. I need a new differential while I'm at it, because the cone-clutches in the Auburn are shot, causing ridiculous axle endplay on the driver's side.

Anyone else agree, or am I alone in this realization lol??

I also need to decide whether to get a set of 3.42's and a new diff and install it in my rear, or just get a used 10 bolt from someone that already has 3.42's and a Torsen diff installed.

**Spaz** · 02-23-2010, 08:39 AM

what rpm are you shifting at???

**5abivt** · 02-23-2010, 08:41 AM

I have argued this in many posts not just to stir the pot but because I believe 4.10s are STUPID for a torquey v-8. I;m glad that someone else feels this way because its true. When I had 4.09s on my vette i got sick of going into 3rd gear before I got across an intersection from a stop. Sure the acceleration FEELS amazing but as soon as you realize how SLOW you are actually moving at the top of 1st gear vs stock gears its like getting bitch slapped by Mike Tyson.

I use 3.73s and my LT4 in my vette and I'm revving 8200 rpm max. I probably should have left 4.10s in it since I rev so high but when I shift at 8200 if puts me right at peak torque with 3.73s and I enjoy the long pull. Also hitting 200+ mph on the 404N was hella sweet.

What i reccomend to everyone with 4.10 gears is to race someone with stock gears from a stop. let the guy with stock gears have the jump and play catch up. You will see just as you start pulling in 1st you run out of rpms and have to shift. What happens when you shift and the other guy is just reaching peak power? He pulls hard away from you.

4.10s would be good if :
You rev 8000 rpms.
need the torque multiplication if you have no torque below 4000 rpm.
Are looking for the quickest 60 ft times and using a slick.

For everything else there's Mastercard.. i mean stock gears.

**Knight** · 02-23-2010, 08:46 AM

40 mph and your in 6th? I've got 4.10s in mine and I'm still in 2nd. I really didn't notice too much of a difference in top end when I switched from 3.42s. Runs a little higher RPM - maybe 500 or so. I guess it all depends on what you want. I've got a lot of other mods and I see the track a lot so 4.10s fit mine well. A dd might be better suited to 3.73s or 3.42s. IMO 4.10s on m6 work well. As for the rear end or carrier switch, IDK, might be a little cheaper with just carrier and gears if you know how to do it.

**Smittro** · 02-23-2010, 08:54 AM

Imho change them out Wes, 4.10's are great for track if you can hook. As you're finding out unless you live @ the track their're not much good for anything else. imho

**Knight** · 02-23-2010, 09:15 AM

Check out this site - www.richmondgear.com/101032.html

If you know your 6th gear ratio (.5 or .65 I think - could be wrong), it will show you your rpms at any speed.

**5abivt** · 02-23-2010, 09:19 AM

6th gear is a FUEL ECONOMY GEAR only on most GM 6 speeds from this era. People need to know our trannies are actually 5 speeds with a fuel saving gear. I believe a lot of people look at cruising speeds in 6th and say 'oh the rpms only drop so much' and think 4.10s are worth it then but the fact is the 1-4 gears take the biggest hit. 5th gear is a larger jump because its for top speed.

A far cry from most other sports cars that have REAL 6 speed trannies where they can obtain top speed in 6th.

**Wesman** · 02-23-2010, 09:22 AM

Originally Posted by Spaz

what rpm are you shifting at???

Originally Posted by Knight

40 mph and your in 6th? I've got 4.10s in mine and I'm still in 2nd. I really didn't notice too much of a difference in top end when I switched from 3.42s. Runs a little higher RPM - maybe 500 or so. I guess it all depends on what you want. I've got a lot of other mods and I see the track a lot so 4.10s fit mine well. A dd might be better suited to 3.73s or 3.42s. IMO 4.10s on m6 work well. As for the rear end or carrier switch, IDK, might be a little cheaper with just carrier and gears if you know how to do it.

When I'm just cruising around, I shift between 2,000 and 2,500RPM. No need to shift higher. Even that those RPM's though, I end up going through 5 gears before I'm up to cruising speed, which is really annoying. So when I'm cruising down a flat road at 40MPH, I just throw it in 6th, which is about 1300RPM.

As I said, even when going to the track it doesn't make any difference. My car is no faster than a car with 3.42's, only difference is I have to shift more lol. I've driven my friends LS2 GTO, which has stock gears, and its so much nicer having the gears taller, yet it still feels just as fast regardless.

**Wesman** · 02-23-2010, 09:23 AM

Originally Posted by Smittro

Imho change them out Wes, 4.10's are great for track if you can hook. As you're finding out unless you live @ the track their're not much good for anything else. imho

Agreed man. Looks like I need to start looking for some 3.42's or a new rear end!!

**Wesman** · 02-23-2010, 09:24 AM

Originally Posted by Knight

Check out this site - www.richmondgear.com/101032.html

If you know your 6th gear ratio (.5 or .65 I think - could be wrong), it will show you your rpms at any speed.

This is the best site I have ever found for gear ratio calculations:

http://www.f-body.org/gears/

Not only does it give you the gear ratios for your car automatically, but it also gives you an entire chart with speed, gear, and RPM.

Thanks for the link though.

Originally Posted by 5abivt

6th gear is a FUEL ECONOMY GEAR only on most GM 6 speeds from this era. People need to know our trannies are actually 5 speeds with a fuel saving gear. I believe a lot of people look at cruising speeds in 6th and say 'oh the rpms only drop so much' and think 4.10s are worth it then but the fact is the 1-4 gears take the biggest hit. 5th gear is a larger jump because its for top speed.

A far cry from most other sports cars that have REAL 6 speed trannies where they can obtain top speed in 6th.

You are right, 6th gear is only for fuel economy. However, our transmissions are actually double overdrive, because 5th gear is O/D as well. Although it sacrifices top speed, I think the gain in fuel economy is more than well worth it.

1st through 4th gears are fine with the stock rear end ratio, there is really no need to make them any shorter. As I said, all it does is make for a hell of a lot more shifting.

**Knight** · 02-23-2010, 09:25 AM

I don't have any trouble getting to top speed in 6th. Pulls like a bat outta hell, but I've also done extensive mods - in a stock car that's probably true. I know when I ran my m5 stang until I modded I had no power in 4th or 5th. I still say 4.10s aren't too bad but that's my opinion. Not as bad as 4.56s!

**Spaz** · 02-23-2010, 09:31 AM

Originally Posted by 5abivt

4.10s would be good if :
You rev 8000 rpms.
need the torque multiplication if you have no torque below 4000 rpm.
Are looking for the quickest 60 ft times and using a slick.

For everything else there's Mastercard.. i mean stock gears.

OR if you have a cam...

**Wesman** · 02-23-2010, 09:32 AM

Originally Posted by Knight

I don't have any trouble getting to top speed in 6th. Pulls like a bat outta hell, but I've also done extensive mods - in a stock car that's probably true. I know when I ran my m5 stang until I modded I had no power in 4th or 5th. I still say 4.10s aren't too bad but that's my opinion. Not as bad as 4.56s!

Mods help with that a lot, stock cars with stock gear don't exactly pull very strongly in 6th gear. They will still keep pulling, but just not all that fast.

Of course, if you have stock gears, you should never have to use 6th gear anyway. 5th will take you all the way up to 183MPH.

**Mr. Luos** · 02-23-2010, 10:23 AM

4.11's in mine.
Thinking about 4.30's. And it sees 95% or more street time.
And I make 325 ft/pounds at 2200RPM

And by the way...if you are getting to the top of 6th gear with even a 4.30...you are risking blowing your car apart.
Not to mention it would require more power than I make...by a bunch.
Oh...and I wish your tranny luck.

**Hi-Po** · 02-23-2010, 10:44 AM

Never understood your point of view on this topic honestly. The conclusion I keep coming to is that you must like to baby your car and keep the RPM's way low. Ive had 4.11's for quite some time, and had 373 before that. If staying NA, I would like to have 4.30's. Never have I felt like I was shifting non stop, but I also never baby the car. If you rarely take the car to redline, or even above 3000 RPM, whats the point of modding the car at all? If your blowing the tires off at the track with your power, your tires are crap and the suspension could use some work. Good luck finding a gear that suits your driving style, seems a stock ratio would work nice in your situation.

**Wesman** · 02-23-2010, 12:17 PM

Originally Posted by Hi-Po

Never understood your point of view on this topic honestly. The conclusion I keep coming to is that you must like to baby your car and keep the RPM's way low. Ive had 4.11's for quite some time, and had 373 before that. If staying NA, I would like to have 4.30's. Never have I felt like I was shifting non stop, but I also never baby the car. If you rarely take the car to redline, or even above 3000 RPM, whats the point of modding the car at all? If your blowing the tires off at the track with your power, your tires are crap and the suspension could use some work. Good luck finding a gear that suits your driving style, seems a stock ratio would work nice in your situation.

I wouldn't say 2,000RPM is way low. When you are just cruising though, why shift higher?? You're just wasting energy. If I want to accelerate faster, then I shift at a higher RPM or downshift. This is expecially true in traffic, I'm not going to go along running each gear to 4,000RPM to avoid shifting less. We have engines that produce a lot of torque, there is no need to shift high all the time.

My car is dual purpose. Its a street car, but it also needs to be fast when I want it to, average decent fuel economy, as well as handle and brake like a sports car. I see absolutely no point in modifications that are detrimental to driveability in a car thats driven on the street 99% of the time. Which is the exact reason why I don't like things like short gearing and huge cams, just not my style. My future goal is to do an LS3 swap, in which case the 3.42's will suit the car much better than the 4.10's.

**5abivt** · 02-23-2010, 01:55 PM

Originally Posted by Mr. Luos

4.11's in mine.
Thinking about 4.30's. And it sees 95% or more street time.
And I make 325 ft/pounds at 2200RPM

SO what you're really saying is.. I have SO much torque down low and I waste it all because of the short gears which 1. Blow the tires off in 1st and 2nd and 2. the rpms fly through the torque band so fast that the torque doesn't get a chance to work.

Remember litre bikes are bigger than 600 cc bikes. they make more torque and are geared LOWER numerically. why? because to use that torque you need to LOAD it so it stays within its torque range LONGER.

a 600cc bike has less torque and revvs higher to make more power. To MAKE UP the torque loss they are geared HIGHER numerically so the torque is multiplied to give greater acceleration.

Look at:

Stock viper final drive.
Formula 1 car final drive.

All of you putting 4.10s in stock torquey low rpm v-8s are basically calling all the engineers on the planet idiots. unless of course you are looking for the most torque with a slick and want to get out of the hole faster. that is the ONLY and I mean ONLY advantage to having gears = 1st gear.
2nd gear isnt really affected by the 4.10s because you are really the SAME as 1st gear in a stock rear car.

**5abivt** · 02-23-2010, 01:56 PM

And to shed some insight on why some cars are Huge dyno queens and run like garbage at the track. Its precisely this reason. Torque needs load.

**Rk ws6** · 02-23-2010, 02:32 PM

4.11s and couldnt be happier...

**Knight** · 02-23-2010, 04:35 PM

Originally Posted by 5abivt

SO what you're really saying is.. I have SO much torque down low and I waste it all because of the short gears which 1. Blow the tires off in 1st and 2nd and 2. the rpms fly through the torque band so fast that the torque doesn't get a chance to work.

This is more of a traction issuse - get the traction and you will see better performance because you'll be putting the power towards accelerating and not spinning tires. You also will accelerate faster - ie going through the torque band quicker = better performance. Never heard of going though the torque band too quickly with an ls1. They are known to have some of the best power curves of most engines.

Originally Posted by 5abivt

All of you putting 4.10s in stock torquey low rpm v-8s are basically calling all the engineers on the planet idiots. unless of course you are looking for the most torque with a slick and want to get out of the hole faster. that is the ONLY and I mean ONLY advantage to having gears = 1st gear.
2nd gear isnt really affected by the 4.10s because you are really the SAME as 1st gear in a stock rear car.

Gears will affect all your gears to an extent - unless your second gear is numerically the same as first gear would be by factoring in the rear end ratio. Usually doesn't work out that way. Granted, depending on the gearing of the transmission , some of the gears will equal out at some point. It's all a numbers game. But also the idea is if you are changing gears, you are usually doing other mods to the car as well. Then gears will play into your build big time. And as for calling engineers idiots - well they did put a weak 7.5" 10 bolt in a car that can snap them like a twig stock. Just sayin...