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I'm new to modding cars and I was just wondering if you need a tune with new gears.
 

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from what I understand you only need a retune to correct the speedometer
 

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AdamZx3 said:
from what I understand you only need a retune to correct the speedometer
That is correct. I would not address the speedo if you plan to do a performance tune later (i.e. CIA, S/C, etc.). You can do both then and save some money rather than getting a handheld tuner for just this change.
 

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he is right....i put em in and waited till my mods were done like offroad x-pipe,cold air and stuff like that then have it tuned on a dyno with an o2 sensor in the exhaust so you can adjust for the air fuel mix and fix the gears at the same time....money well spent............:cool:
 

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More Info?

Wanting a little more info on a gear change. Everyone seems to be saying 4.10's. I wanted to know what exactly is changed with these? Do you simply have to shift earlier as the rpm's ramp up more quickly?
 

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Yes,.......not a bad way to describe it.......but the real advantage is the greater torque multiplication. I.E. Hang on tight cause mother really pulls now!!!:eyepoppin
 

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Go with the 4.10 gears, and use the Ford parts. This is the best mod you can do, regardless of whether you go with any power adders. It totally transforms the car. At 70mph in 5th, you only turn 2500 RPM. To correct the speedo, you have to own a Predator or SCT handheld anyway for these cars. Why would you want to drive around with the wrong speedo reading? It bothered me the one day I drove the car before I got around to adjusting it.
 

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boss377 said:
Go with the 4.10 gears, and use the Ford parts. This is the best mod you can do, regardless of whether you go with any power adders. It totally transforms the car. At 70mph in 5th, you only turn 2500 RPM. To correct the speedo, you have to own a Predator or SCT handheld anyway for these cars. Why would you want to drive around with the wrong speedo reading? It bothered me the one day I drove the car before I got around to adjusting it.
Was thinking (and was recommended) to get the predator as well - so shouldn't be a problem. I think stock rpms's @ 60mph is something like 1900rpm's? Anyways, I was more curious about the day-to-day 'real-world' changes from the stock settings.

My last car, an 05 Subaru STi, had a factory speedo that was off. When I got my car dyno tuned, my tuner said it read 42mph when it was only going 37mph. I knew it was off, didn't know it was that much. I just figured it helped me to NOT get a speeding ticket - didn't mind.
 

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boomn29 said:
Anyways, I was more curious about the day-to-day 'real-world' changes from the stock settings.
Checked my rpm's on my stock 05 today:

5th gear @ 55mph - 1750rpms
5th gear @ 80mph - 2400rpms.

Wondered if someone with 4.10's could chime in on their differences?
 

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27.2" tall tire, 60 MPH, 4th gear (1:1)

Gear RPM
3.55 2632
3.73 2766
3.90 2892
4.10 3040
4.30 3188
 

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RPM said:
27.2" tall tire, 60 MPH, 4th gear (1:1)

Gear RPM
3.55 2632
3.73 2766
3.90 2892
4.10 3040
4.30 3188
Thanks. Stupid me, not going for the 1:1 gear. Really appreciate this. Doesn't seem like a huge difference on paper really in rpm's. All the comments I read say 'it totally transforms the car', and 'it's a blast to drive now', but nothing more!
 

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The big difference comes in how fast the car revs in each gear. You have to accelerate X MPH to get to your shift point (lets say it's 6200RPM and it's 42 MPH in first w/ 3.55s). With 4.10s you will be shifting in a tighter MPH range even though the RPM drops in each gear are the same. Here's an example of what MPH you will be going with each shift at 6200:

.....................3.55 4.10
1st to second .. 42 ...36

2nd to third ..... 71 ...61

3rd to 4th ....... 106 ..92

You will be able to use 4th a little in the 1/4 assuming you car will trap at 92 MPH or more.

Can't get the numbers to line up in columns:mad:
 

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Shortfall of 4.10s ?

Hi,

What I would hope to know before swapping gear (and deciding between 3.90 versus 4.10) is exactly what it will do to the car. I find it already pulls nice, my main complaint being how short first is before having to shift to second. I even sometimes get lazy, as I usually like to accelerate swiftly from a stoplight. So I keep it in second, and gently ease it from a standstill, then once I'm launched I gun it, staying in second in town as it will - according to the above chart - not need to shift again until reaching 71mph with the stock 3.55 gearing.

What will 4.10 do for me, other than increase the risk of engine lugging when launching in second, and force a shift into third during hard acceleration?

Please, no flames for civic behavior, I only drive "peppy" when there is clear visibility and absence of pedestrians.

Vic
 

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Vic,
The 4:10's vs stock will result in you shifting sooner at a comparable MPH. The benefit will be quicker response off the line and each subsequent shift. The down side it you will be shifting sooner and give up some top-end speed in 4th gear. The MPG delta is nominal.

Frankly, your decision between 3:90 & 4:10 won't be that noticeable, since it's only a 5% change in ratio.
 

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Launching in second would be easier with the 4.10's, your stated propensity for lazy shifting would be exaserbated. Rev's will climb quicker.....urge to shift sooner.

Good Luck:thumbsup
 

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I wish it was a 6 speed. :tongue I would'nt hesitate to drop a higher gear in.
 

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To correct the speedo for adding 4.10's with a predator, what and how much do you change??
 

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ON THE SCT2 YOU JUST CHANGE IT TO THE CORRECT RATIO....I WOULD ASSUME IT WOULD BE THE SAME?????:cool:
 
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