1/4 mile gains going from 3.42s to 3.90s
10-06-2004, 11:00 AM
#31
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I dropped 9/10 of a second with a CAI and 4.10 gears with posi. I don't think the CAI did much of that gain.
I just got 20 mpg on a long freeway trip going 70-80mph with a bit of driving around town too.
Any way you look at it you will be shifting into 3rd in the quarter mile. Unless you want to rev it to somewhere past 6000rpms...scary. With my 4.10s and my 30 or so inch tires I'd finish 3rd gear at 6000rpms at a theoretical speed of 131 mph. Thats alot of potential there.
The 3.42s will just give you more mph in 3rd gear. So if your motor can pull hard enough you will have more potential in the 1/4. If you aren't making enough power than those 3.42s will just slow you down.
The only reason to go with a taller gear is to cut down on a shift. If you can finish the 1/4 in second well thats a good thing, only one shift slowing you down. So far I can only see 3.23 gears allowing me to finish in second, as I am concerned with revving past 6000rpms.
If you are thinking of getting 3.90 gears than you should just stick with 3.73s. If you need more gear than that then go 4.10s. Unless the 3.90s are a stronger gear. How many teeth are on the pinion on the 3.90s and how many are on the ring gear?
I just got 20 mpg on a long freeway trip going 70-80mph with a bit of driving around town too.
Any way you look at it you will be shifting into 3rd in the quarter mile. Unless you want to rev it to somewhere past 6000rpms...scary. With my 4.10s and my 30 or so inch tires I'd finish 3rd gear at 6000rpms at a theoretical speed of 131 mph. Thats alot of potential there.
The 3.42s will just give you more mph in 3rd gear. So if your motor can pull hard enough you will have more potential in the 1/4. If you aren't making enough power than those 3.42s will just slow you down.
The only reason to go with a taller gear is to cut down on a shift. If you can finish the 1/4 in second well thats a good thing, only one shift slowing you down. So far I can only see 3.23 gears allowing me to finish in second, as I am concerned with revving past 6000rpms.
If you are thinking of getting 3.90 gears than you should just stick with 3.73s. If you need more gear than that then go 4.10s. Unless the 3.90s are a stronger gear. How many teeth are on the pinion on the 3.90s and how many are on the ring gear?
10-06-2004, 11:02 AM
#32
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Originally Posted by marc_w
This is my exact reasoning when it comes to gearing.
I've got 22mpg in my truck with 4.10's and 30.5" tires. I get better mileage driving around in 3rd with the RPM's up around 2K, as opposed to lugging OD/Lockup up hills at around 1,300rpm for example. I changed my shift patterns to help me out there.
I'd look into 4.56's if I didn't have a front diff to worry about. I love short gearing.
I've got 22mpg in my truck with 4.10's and 30.5" tires. I get better mileage driving around in 3rd with the RPM's up around 2K, as opposed to lugging OD/Lockup up hills at around 1,300rpm for example. I changed my shift patterns to help me out there.
I'd look into 4.56's if I didn't have a front diff to worry about. I love short gearing.
10-06-2004, 11:06 AM
#33
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Originally Posted by MacADaYear
Yea but what are you gonna do when you pull super hard to 60 mph then fall flat on your face because your out of gear?
With Chingys setup he will rape me till about 70, then ill come back and pass him. So what do you finish your 1/4 at? I know its more than 70 mph
Its not like if you add 410s you get more pull and more top end, something has to give. Take off is great, but I dont like to rip *** off the line then get my *** handed to me at the end
Also if you look at the fastest truck list there arnt many running 410s. Most 373s if I remember correctly.
With Chingys setup he will rape me till about 70, then ill come back and pass him. So what do you finish your 1/4 at? I know its more than 70 mph
Its not like if you add 410s you get more pull and more top end, something has to give. Take off is great, but I dont like to rip *** off the line then get my *** handed to me at the end
Also if you look at the fastest truck list there arnt many running 410s. Most 373s if I remember correctly.
As far as the fastest truck list, I'd say most use 3.73 gears because thats what they came with stock and they have the potential for alot more mph in the 1/4 in 3rd gear (or second for those who go to nearly 7000 rpms) which you need to get better times. Also deeper gears are often a poor mans performance solution which is why many of them are quick but not super fast.
10-06-2004, 11:10 AM
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Originally Posted by snoman
There is in the quality and quietenss of of 4.10's vs 3.90's. I would never use a richmond gear myselff as they are a "cheap" gearset. Also 3.73, 4.10, 4.56 are al supported by GM ECM programing directly where a 3.90 is not. And finailly, yes there is not much difference between them performance wise but if you install a 3.90 and run a 14.93, you will alway wonder if it would have been a 14.8 something or less with a 4.10. Personally, I would install a 4.56 as I love the launchs and pulling power it give you and throw in OD and you have the best of both worlds. When I need great gas milage, I do not drive my 5000lb plus truck anyway so I am not going to try for a extra .5 mpg in exchange for marginal performance.
10-06-2004, 07:01 PM
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Originally Posted by TigerFan187
I was running Firehawk Indy 500's stock 16" rim and I finish te 1/4 in 3rd! When I get a stall i dont plan on ahving traction issues either!
snoman, is it worth the $ changing a 3.73 to a 4.10? is it settled that a 4.56 is way to much gear on a 1/2 ton w/ 4l60e?
10-06-2004, 07:26 PM
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Originally Posted by revolution
i have a 2600 stall 3.73 gears with a G80 locker and indy 500s and a traction problem off the line (street)... i can spin the tires all thru 1st gear - thats not even brake stalling - just punching it from the line. are you talking about at the track? does heating the tires help?
snoman, is it worth the $ changing a 3.73 to a 4.10? is it settled that a 4.56 is way to much gear on a 1/2 ton w/ 4l60e?
snoman, is it worth the $ changing a 3.73 to a 4.10? is it settled that a 4.56 is way to much gear on a 1/2 ton w/ 4l60e?
4.56s wouldn't be too bad of a gear. With 30" tires you'd be cruisin at around 2000 rpms at 55mph. At 2500 rpms youd be at 70 mph. Not too terrible.
10-07-2004, 05:11 PM
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Originally Posted by revolution
i have a 2600 stall 3.73 gears with a G80 locker and indy 500s and a traction problem off the line (street)... i can spin the tires all thru 1st gear - thats not even brake stalling - just punching it from the line. are you talking about at the track? does heating the tires help?
snoman, is it worth the $ changing a 3.73 to a 4.10? is it settled that a 4.56 is way to much gear on a 1/2 ton w/ 4l60e?
snoman, is it worth the $ changing a 3.73 to a 4.10? is it settled that a 4.56 is way to much gear on a 1/2 ton w/ 4l60e?
10-07-2004, 05:31 PM
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Originally Posted by revolution
i have a 2600 stall 3.73 gears with a G80 locker and indy 500s and a traction problem off the line (street)... i can spin the tires all thru 1st gear - thats not even brake stalling - just punching it from the line. are you talking about at the track? does heating the tires help?
snoman, is it worth the $ changing a 3.73 to a 4.10? is it settled that a 4.56 is way to much gear on a 1/2 ton w/ 4l60e?
snoman, is it worth the $ changing a 3.73 to a 4.10? is it settled that a 4.56 is way to much gear on a 1/2 ton w/ 4l60e?
10-07-2004, 05:42 PM
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Originally Posted by snoman
but when you hit second and then 3rd and the stall is gone
Originally Posted by snoman
the 3.73 is a boat anchor is a big truck and a 4.10 or 4.56 comes into its own. It todays trucks with OD I would not even own one with a 4.10 even if I never planed on taking it to the strip.
