EX 5-speed regear or replace?
12-29-2013
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EX 5-speed regear or replace?
I bought my 05 EX Special Edition last summer as a thrifty commuter car, and I'm somewhat dismayed that it's geared so low. I don't care to be running at over 4,000 rpm on the interstate. The clutch is going to need replacing soon, (-ish) and since that requires pulling the trans out, I want to either regear the differential for better highway economy or source a 5-speed from a lower model and rebuild it to swap in. I do want to keep the limited slip in my trans...
Anyone done this? pros/cons? worth the cost? or should I just replace the clutch and live with a high-revving motor and lose fuel economy on the interstate?
Anyone done this? pros/cons? worth the cost? or should I just replace the clutch and live with a high-revving motor and lose fuel economy on the interstate?
12-29-2013
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Re: EX 5-speed regear or replace?
Honestly, unsure. My ex manual clocks better mpg than my former lx auto, but too many variables (gearing, auto, vtec, etc.) Potentially could be worse depending on power band/roads.
12-29-2013
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If you think a good mechanic is expensive, try hiring a bad one
Re: EX 5-speed regear or replace?
I don't care to be running at over 4,000 rpm on the interstate.
01-01-2014
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Slow down. Its free.
The EPA difference between an 05 LX and EX is 1 mpg. That would take 100,000 miles to recoupe if the trans cost $200 and gas was $3.25.
The EPA difference between an 05 LX and EX is 1 mpg. That would take 100,000 miles to recoupe if the trans cost $200 and gas was $3.25.
01-01-2014
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That's in 5th gear...
On a trip home to Washington state (900 miles one way):
First tank, sustained speeds of ~80mph, ethanol free fuel = 36.3mpg
Second tank, speeds of ~60mph, ethanol blend gas = 35.1
Third tank, speeds of ~70mph, ethanol crap gas = 35.2
Fourth tank, speeds of 80-85, ethanol junk gas = 32.6
Not what I was hoping for, and you can see how the ethanol affected my fuel economy, as well as my speed. I would think that even at 80 mph, running 500-1000 slower would make it run much more efficiently, as I never coasted down even steep grades, and cancelling the cruise acted more like hitting the brakes. Guess that's why Honda went with a 6 speed the next year huh?
On a trip home to Washington state (900 miles one way):
First tank, sustained speeds of ~80mph, ethanol free fuel = 36.3mpg
Second tank, speeds of ~60mph, ethanol blend gas = 35.1
Third tank, speeds of ~70mph, ethanol crap gas = 35.2
Fourth tank, speeds of 80-85, ethanol junk gas = 32.6
Not what I was hoping for, and you can see how the ethanol affected my fuel economy, as well as my speed. I would think that even at 80 mph, running 500-1000 slower would make it run much more efficiently, as I never coasted down even steep grades, and cancelling the cruise acted more like hitting the brakes. Guess that's why Honda went with a 6 speed the next year huh?
Last edited by noJeepshere; 01-01-2014 at 10:35 PM.
01-02-2014
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I still think your right foot is the biggest culprit. I run ethanol and can pull off 40mpg at 75. I drive smoothly though. I don't weave and constantly accelerate/decelerate.
Jack your car and check for drag on all 4 wheels. Also, pump your tires up to the highest PSI you are comfortable running them at, but at least what the placard says. Mine are at 40 PSI. Also, check the basics, plugs, filter, etc.
Jack your car and check for drag on all 4 wheels. Also, pump your tires up to the highest PSI you are comfortable running them at, but at least what the placard says. Mine are at 40 PSI. Also, check the basics, plugs, filter, etc.
01-02-2014
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I have done EVERYTHING in my power to get 40 MPG out of my "EX" civic. It is very hard to do simply because the car is not geared for economy. As efficient as the engine is at 4000 rpms it will simply NOT do well. Even at 60mph it's revving over 2500 if I recall correctly. You will do a little better with an LX but not significantly. It's really hard to say if it's worth it however everyone is right. If you slowed down you would save a pretty drastic amount of gas. Your best fuel economy is around 40mph and its a decrease from there on.
01-02-2014
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I have done EVERYTHING in my power to get 40 MPG out of my "EX" civic. It is very hard to do simply because the car is not geared for economy. As efficient as the engine is at 4000 rpms it will simply NOT do well. Even at 60mph it's revving over 2500 if I recall correctly. You will do a little better with an LX but not significantly. It's really hard to say if it's worth it however everyone is right. If you slowed down you would save a pretty drastic amount of gas. Your best fuel economy is around 40mph and its a decrease from there on.
What kind of tires are you running? LRR? Are they at the correct pressure? Are they the correct size? Do you have the stock 14 or 15 inch wheels?
If the car is stock and running correctly, and you aren't getting around EPA mileage, your driving most likely needs work.
01-02-2014
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Wow...I get 34 around town...I must drive a lot different.
Instead of changing the trans out, one could always go with slightly taller tires. just remember, the speedometer and odometer is going to be off.
Instead of changing the trans out, one could always go with slightly taller tires. just remember, the speedometer and odometer is going to be off.
01-02-2014
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Re: EX 5-speed regear or replace?
I'm a more spirited driver. Even in the summer when I take the back roads home and push her more to the limits I get around 32 (with summer tires). Now I have winter tires and more highway so I'm pushing closer to 34.
Not worth the trouble of changing the trans out for a few MPG, IMO.
Not worth the trouble of changing the trans out for a few MPG, IMO.
01-02-2014
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2500 and 4000 rpm is a big difference. 4000 rpm is over 80. Slow down for better economy.
What kind of tires are you running? LRR? Are they at the correct pressure? Are they the correct size? Do you have the stock 14 or 15 inch wheels?
If the car is stock and running correctly, and you aren't getting around EPA mileage, your driving most likely needs work.
What kind of tires are you running? LRR? Are they at the correct pressure? Are they the correct size? Do you have the stock 14 or 15 inch wheels?
If the car is stock and running correctly, and you aren't getting around EPA mileage, your driving most likely needs work.
I'm not sure if you even read my post?
What year is your civic? My 2005 I had to drive veeeeerrrryyy carefully to get 30MPG in the city. From what I've seen on Fuelly.com, this rings true to every other civic in the world. 7th gen anyway.
01-02-2014
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I don't drive that well...
01-02-2014
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I agree on the reduce speed.
up north, where the posted speed was 65MPH, was the best ever MPG i got, 44MPG. of course the huge weight of all my stuff in the car (moving from canada back to TN) helped a lot.
Also, unsure where the most efficient point is on the EX engine, but much depends on the power/torque band and where the engine is most efficient.
the best guys to answer that question would be the ones that swapped the EX head into a LX, but not sure if any of them will reply - they mostly simply come to ask questions and disappear into the darkness.
noJeepshere,
just give it a try and run at 70-75 for one tank and check again. you might be pleasantly surprised.
up north, where the posted speed was 65MPH, was the best ever MPG i got, 44MPG. of course the huge weight of all my stuff in the car (moving from canada back to TN) helped a lot.
Also, unsure where the most efficient point is on the EX engine, but much depends on the power/torque band and where the engine is most efficient.
the best guys to answer that question would be the ones that swapped the EX head into a LX, but not sure if any of them will reply - they mostly simply come to ask questions and disappear into the darkness.
noJeepshere,
just give it a try and run at 70-75 for one tank and check again. you might be pleasantly surprised.
01-08-2014
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I can tell the consensus is to just leave it be... oh well, just a thought.
Part of the reason I was going so fast was that I needed to go to work in the morning and I was running behind schedule, so I was taking advantage of northern Utah's 80mph speed limit.
Normally I don't even bother looking at the speed limit sign, I just do somewhere around 70-72, even in a 75 zone. (Habit from my truck)
I just went to Rexburg and back, and my friend drove up, doing ~80 the whole way, 32mpg on the tank. I drove back, doing 72, and got... I don't know yet, but I've 267 miles on just over half a tank, so pretty good.
Thanks for your input y'all.
Part of the reason I was going so fast was that I needed to go to work in the morning and I was running behind schedule, so I was taking advantage of northern Utah's 80mph speed limit.
Normally I don't even bother looking at the speed limit sign, I just do somewhere around 70-72, even in a 75 zone. (Habit from my truck)I just went to Rexburg and back, and my friend drove up, doing ~80 the whole way, 32mpg on the tank. I drove back, doing 72, and got... I don't know yet, but I've 267 miles on just over half a tank, so pretty good.
Thanks for your input y'all.
01-08-2014
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01-08-2014
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If you think a good mechanic is expensive, try hiring a bad one
01-08-2014
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2500 and 4000 rpm is a big difference. 4000 rpm is over 80. Slow down for better economy.
What kind of tires are you running? LRR? Are they at the correct pressure? Are they the correct size? Do you have the stock 14 or 15 inch wheels?
If the car is stock and running correctly, and you aren't getting around EPA mileage, your driving most likely needs work.
What kind of tires are you running? LRR? Are they at the correct pressure? Are they the correct size? Do you have the stock 14 or 15 inch wheels?
If the car is stock and running correctly, and you aren't getting around EPA mileage, your driving most likely needs work.
I drive just fine thankyouverymuch. Most of the time in normal driving I get anywhere's from 36-38 mpg. This high speed run is unusual for me in that I never travel at such speeds in normal situations. I rev the motor to 3,000 rpm in each gear and go up to half-throttle, if that.
01-09-2014
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I just have some 195/65-15 tires on the stock aluminum wheels, Grenada's iirc. Correct size for the car.
I drive just fine thankyouverymuch. Most of the time in normal driving I get anywhere's from 36-38 mpg. This high speed run is unusual for me in that I never travel at such speeds in normal situations. I rev the motor to 3,000 rpm in each gear and go up to half-throttle, if that.
I drive just fine thankyouverymuch. Most of the time in normal driving I get anywhere's from 36-38 mpg. This high speed run is unusual for me in that I never travel at such speeds in normal situations. I rev the motor to 3,000 rpm in each gear and go up to half-throttle, if that.
I asked about tire and wheel size because oversize (even 1") can lower gas mileage. For your next set of tires, look into some LRR's. They can improve mileage. I love mine. They work well in dry and wet conditions and I expect them to work in the snow, though we really don't get snow here. But, some LRR's suck all around so do the research.
I usually shift at 2,000 minimum and 2,600 max. My last tank was 36 in the city, well, suburban city. I hit traffic lights, but the speed limits are between 35 and 55. I also sit in a little traffic both to and from work, not moving, which is 0 mpg.
Last edited by MPGFTW; 01-11-2014 at 07:31 PM.
01-11-2014
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01-12-2014
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If you are getting 36-38 hwy, then you are driving okay. That sounds a lot better than 32!
I asked about tire and wheel size because oversize (even 1") can lower gas mileage. For your next set of tires, look into some LRR's. They can improve mileage. I love mine. They work well in dry and wet conditions and I expect them to work in the snow, though we really don't get snow here. But, some LRR's suck all around so do the research.
I usually shift at 2,000 minimum and 2,600 max. My last tank was 36 in the city, well, suburban city. I hit traffic lights, but the speed limits are between 35 and 55. I also sit in a little traffic both to and from work, not moving, which is 0 mpg.
I asked about tire and wheel size because oversize (even 1") can lower gas mileage. For your next set of tires, look into some LRR's. They can improve mileage. I love mine. They work well in dry and wet conditions and I expect them to work in the snow, though we really don't get snow here. But, some LRR's suck all around so do the research.
I usually shift at 2,000 minimum and 2,600 max. My last tank was 36 in the city, well, suburban city. I hit traffic lights, but the speed limits are between 35 and 55. I also sit in a little traffic both to and from work, not moving, which is 0 mpg.
01-12-2014
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If you think a good mechanic is expensive, try hiring a bad one
01-12-2014
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And the test I do is jack the wheels off the ground, leave it in neutral and turn one of the tires by hand, if the opposite one spins backward, I've got an LSD, if it doesn't turn at all, it's open. I did that and it spins backward.
01-12-2014
#28
If you think a good mechanic is expensive, try hiring a bad one
Re: EX 5-speed regear or replace?
And the test I do is jack the wheels off the ground, leave it in neutral and turn one of the tires by hand, if the opposite one spins backward, I've got an LSD, if it doesn't turn at all, it's open. I did that and it spins backward.
Jack one front wheel off the ground so it can spin free.
Leave the other on the ground.
Start engine, put in gear, dry to drive it off the jack.
If it has a limited slip, the wheel with traction WILL drive the car.
If it is an open diff, the free spinning wheel will just spin freely.
01-13-2014
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^ agree
01-16-2014
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You have an open differential, you just found which mechanical path has the least resistance.
Jack one front wheel off the ground so it can spin free.
Leave the other on the ground.
Start engine, put in gear, dry to drive it off the jack.
If it has a limited slip, the wheel with traction WILL drive the car.
If it is an open diff, the free spinning wheel will just spin freely.
Jack one front wheel off the ground so it can spin free.
Leave the other on the ground.
Start engine, put in gear, dry to drive it off the jack.
If it has a limited slip, the wheel with traction WILL drive the car.
If it is an open diff, the free spinning wheel will just spin freely.
