Gear Ratio

FlashPro questions & answers specific to the 2006-2011 Americas Civic Si
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dvergara
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Gear Ratio

Post by dvergara »

Hello Honda. Please help.

I have a 2010 Civic Si and it's now turbocharged. I'm changing the gears to PPG, but when I enter the ratio in the program, the computer isn't giving me the correct gear. For example, I'm in 3rd gear and it tells me I'm in 1st gear. I'm in 4th gear and it tells me I'm in 2nd gear. I need this information to be correct to program the boost by gear.

klh.jpg
klmh log.jpg
When I leave the factory settings... the Honda tells me that all the gears are 6th
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Hondata
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Re: Gear Ratio

Post by Hondata »

You need to enter the correct number of teeth for 3rd gear.
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dvergara
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Re: Gear Ratio

Post by dvergara »

radio.jpg
I don't understand. I'm adding the radius the manufacturer gave me.
Can you explain to me please?
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Hondata
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Re: Gear Ratio

Post by Hondata »

The ECU (and dash) senses speed from a sensor in the transmission which detects the teeth on the countershaft 3rd gear. Stock has 44 teeth. You probably have around half that number. The ratio does not matter - only the number of teeth.

Also if you change that gearset make sure the sensor is not going to hit the teeth nor be too far from them to sense.
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dvergara
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Re: Gear Ratio

Post by dvergara »

Thanks. Is the sensor you're talking about the speed sensor? I've already separated it enough so it doesn't touch. I didn't count the teeth on my 3rd gear. I'll try to put half of them in.

Thanks.
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Spunkster
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Re: Gear Ratio

Post by Spunkster »

Yes, it is the speed sensor.
dvergara
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Re: Gear Ratio

Post by dvergara »

Hello again. My 3rd gear has 21 teeth. I tried 21, but it didn't work. I also tried 20, 21, 22, 23, and 24, but nothing worked.
dvergara
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Re: Gear Ratio

Post by dvergara »

The speed varies when I change the number of teeth but it always tells me that I am in 1st gear
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Spunkster
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Re: Gear Ratio

Post by Spunkster »

Is the speed correct?
Supa Ninja
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Re: Gear Ratio

Post by Supa Ninja »

I am having the exact same issue.

2006 Si, turbo, PPG taller gears, 3rd gear is 23 teeth


Problem, on my data logs VSS is reading what my speed would be is kept third gear as 44 teeth, about half as fast I’m really going. The computer things it’s in 1st until I get to 4th then it thinks it’s in 2nd. This is really screwing up my boost by gear.

Another weird thing I have noticed is when I upload a new tune to the ecu, I have to first go to the calibrate page and retype in 23 teeth or else it will default to 44 teeth and give me a wrong speedometer speed. Other than these two issues my flashpro is awesome.
Supa Ninja
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Re: Gear Ratio

Post by Supa Ninja »

Well I feel like an idiot for not trying this sooner. On the ecu speed correction I entered 100%, now it’s picking up all the gears and I get use all my boost 🎉
jdmfg22010
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Re: Gear Ratio

Post by jdmfg22010 »

I did the same few hours ago and it worked but the car stalled and wont turn on until I changed the percentage back to 0% smh
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