vx owner wants more mpg!

[silversol]

well a cx to vx converted owner wants more mpg!. i have had the vx swap in for almost 600 miles now and i get around 44 mpg mainly city driveing. and that is driving with a lot of angry people behind me shifting below 2500rpms coasting down hills. 55psi in the tires with vx wheels and the intake turned to the radiator.
I try my best to stay in lean mode at all times. and driving like there is a egg under the gas pedal. call it greed but i want more i want to break 50mpg so bad!. should i turn the car off at lights and restart when green? should i shut it down coasting? and restart? i am willing to try just about anything except crazy aero mods besides a grill block thats on my to do list. thanks in advance!

[cems70]

Originally Posted by silversol

should i turn the car off at lights and restart when green? should i shut it down coasting? and restart? i am willing to try just about anything except crazy aero mods besides a grill block thats on my to do list. thanks in advance!

I turn off my engine ('95 Civic DX hatchback) at all red lights that are 10 seconds or longer. I also do engine off coasting at EVERY opportunity. I do a mix of highway and very light city and/or secondary roads (w/ few traffic lights) driving. I'm certain the engine off coasting and shutting off the engine at traffic lights makes a big difference. I did not do this often when I first bought the car 1.5 years ago, but it's been my standard hypermiling techniques for the past several months. Look at my mileage entries. I'll bet you can break 50 mpg w/ your much more economical VX by using these techniques, even if most of your driving is in the city.

[BIBI]

50 mpg/city, you will get that with a hybrid, 44 mpg in city with a VX is exelent.
Do some highway, or travel less if 44mpg is not enough.

[silversol]

most of my driving is 75% atlanta city driving 25% hwy. i am going to try shutting it off and lights and coasting and compression starting when coasting. 44 mpg is ok. but i see several vx owners claiming as much as 55mpg!

[silversol]

cems70 are you really getting 56.49 mpg out of a dx!! slaps forhead! what am i doing wrong!

[Danronian]

I've really never seen any VX owners claim over mid-40s for city driving.

The VX doesn't have the best gearing for city driving I don't think. The best I have ever gotten on non-highway driving in my VX is lately when I've gotten 43 mpg in the heat of summer and going right around the speed limit.

Good luck with it!

[suspendedhatch]

Increasing power increases your city mpg. But just about anything you do to attempt to increase power in a VX does more harm than good. A turbo and a recalibrated ECU would be your best bet, but it would be a costly conversion not likely to ever pay for itself. Still, in theory, you'd be naturally aspirated 90% of the time, but the boost would be there when you need it and could help you get up to cruising speed quicker. Then back off the throttle and the load will drop back down again.

Nothing wastes gas more than going up a steep hill with a weak engine.

[silversol]

Originally Posted by suspendedhatch

Increasing power increases your city mpg. But just about anything you do to attempt to increase power in a VX does more harm than good. A turbo and a recalibrated ECU would be your best bet, but it would be a costly conversion not likely to ever pay for itself. Still, in theory, you'd be naturally aspirated 90% of the time, but the boost would be there when you need it and could help you get up to cruising speed quicker. Then back off the throttle and the load will drop back down again.

Nothing wastes gas more than going up a steep hill with a weak engine.

i too have thought of the turbo idea. and yes hills just kill my vx. i built a turbo gsr delsol a few years ago that made great power. i was thinking of a very small turbo like a tdo4 and only having the boost set a 3psi 4 max! and keeping the stock ecu i dont think with that small a turbo and that psi could hurt much. but what i was thinking was about the heat i know that heat will increase mpg either not intercooling or running a very small intercooler.

[cems70]

Originally Posted by silversol

cems70 are you really getting 56.49 mpg out of a dx!! slaps forhead! what am i doing wrong!

I swapped the DX tranny for a VX tranny not long after I bought the car. That change alone gets me to about 46 -48 mpg. Driving 55 mph or less on the highway gets me to about 50 - 52 mpg. My hypermiling (EOC, turn off engine at stop lights etc.) gets me to 56.49 mpg.

[silversol]

ok guys i am doing something seriously wrong! i just filled up and i got 35 mpg this tank!!!!! and that is driving very slow shifting a 2500! and some eoc! god what am i do in wrong!!!

[BIBI]

Originally Posted by cems70

I swapped the DX tranny for a VX tranny not long after I bought the car. That change alone gets me to about 46 -48 mpg. Driving 55 mph or less on the highway gets me to about 50 - 52 mpg. My hypermiling (EOC, turn off engine at stop lights etc.) gets me to 56.49 mpg.

The transmission is in fact one of the biggest think that make the VX so FE. Go ask the automakers WHY they havent continued with that kind of thinking. I personnaly experiment my VX with a SI tranny (I had to change the tranny when I bought the car, but someone sell me the wrong transmission so I had a SI tranny for 2-3 weeks) and my MPG dropped dramaticaly).

Good thing to notice is that a DX with a CX/VX tranny get the same MPG then a CX with +/- 20hp less.

[opelgt73]

Originally Posted by cems70

I swapped the DX tranny for a VX tranny not long after I bought the car. That change alone gets me to about 46 -48 mpg. Driving 55 mph or less on the highway gets me to about 50 - 52 mpg. My hypermiling (EOC, turn off engine at stop lights etc.) gets me to 56.49 mpg.

I wonder how much better mileage you would get with an HF tranny in a VX. I noticed one guy with a D15Z1 and an HF trans in his crx is reporting mid 60's with that combination.

I think I may do that swap into a CRX Si after I finish my current HF project.

[BIBI]

Originally Posted by opelgt73

I wonder how much better mileage you would get with an HF tranny in a VX. I noticed one guy with a D15Z1 and an HF trans in his crx is reporting mid 60's with that combination.

I think I may do that swap into a CRX Si after I finish my current HF project.

The mid 60's are more the fact that a crx weight 1600-1800 and a VX 2100. Because from what I hear on this forum, the HF tranny dont match really well the VX power band. Maybe just the long five of the HF combined with a VX tranny.

[opelgt73]

Originally Posted by BIBI

The mid 60's are more the fact that a crx weight 1600-1800 and a VX 2100. Because from what I hear on this forum, the HF tranny dont match really well the VX power band. Maybe just the long five of the HF combined with a VX tranny.

My HF (2nd gen) is more like 2100. The first gen hf was the ~1600lb one.

What do you mean long five of the HF combined with the VX tranny?

[opelgt73]

Originally Posted by BIBI

Because from what I hear on this forum, the HF tranny dont match really well the VX power band.

Does anyone have any empirical evidence to prove this?

[Brian D.]

I was able to get 52MPG CONSISTENTLY with my '91 HF (FED) when I had it...I mean consistently! I see now reason why these VX'ers out there have to settle for less. Sure, the VX weighs a few more pounds than my "heavy" 1991 CRX HF) REALLY offset the increased efficiency of the Civic VX engine, (which should be way MORE efficient than the HF engine)? I would think VX'ers should be getting a consistent 50MPG with NO problem. I never did ANYTHING ridiculous to get my 52MPG in my HF-fed...totally normal driving, never killing the ignition, and never overinflating the tires. That car was AMAZING. There was never a fill-up where I didn't do the gallons-versus-miles-driven calculation.

[nowhhs]

Originally Posted by opelgt73

Does anyone have any empirical evidence to prove this?

Proof is relative. I've found that the final drive of the hf transmission, 2.95 vs 3.25 in the vx/cx, makes starting out in first a bit of a PITA, especially if you're in a hurry. This in a 90 hatch at ~2150#s. Course it doesn't help that I add another 250#s

[cems70]

Originally Posted by cems70

I swapped the DX tranny for a VX tranny not long after I bought the car. That change alone gets me to about 46 -48 mpg. Driving 55 mph or less on the highway gets me to about 50 - 52 mpg. My hypermiling (EOC, turn off engine at stop lights etc.) gets me to 56.49 mpg.

Originally Posted by BIBI

Good thing to notice is that a DX with a CX/VX tranny get the same MPG then a CX with +/- 20hp less.

Yes, but the DX power band does not match up well w/ the CX/VX tranny. It's a real dog unless it's in the 3,000+ RPM range...and I almost never get into that range unless I really need to accelerate fast. Frankly, for the type of driving I do, I'd rather have a CX (or a VX, of course).

And if you think it's difficult starting out in first gear in a VX with the HF tranny, try my DX with the VX tranny.

All that said, FE is the most important thing to me, and I'm pretty pleased with it this summer.

[1993CivicVX]

Originally Posted by silversol

well a cx to vx converted owner wants more mpg!. i have had the vx swap in for almost 600 miles now and i get around 44 mpg mainly city driveing. and that is driving with a lot of angry people behind me shifting below 2500rpms coasting down hills. 55psi in the tires with vx wheels and the intake turned to the radiator.
I try my best to stay in lean mode at all times. and driving like there is a egg under the gas pedal. call it greed but i want more i want to break 50mpg so bad!. should i turn the car off at lights and restart when green? should i shut it down coasting? and restart? i am willing to try just about anything except crazy aero mods besides a grill block thats on my to do list. thanks in advance!

What is it with 44mpg being the magic number for this car? So many VX owners are getting 44mpg. I hate to rub it in (okay, I don't) but for me I have to drive pretty carelessly to get 44mpg. Your description sounds like you should be getting 56-62mpg. But there is no reason to go above 2000RPM let alone 2500rpm. My car is bone stock minus a front spoiler/lip and I have no problem getting 50+mpg. The single biggest thing I think you can do to gain 10mpg would be the following: On flat ground in 1st gear shift at 1800RPMs, in 2nd gear shift at 1700rpm, in 3rd gear shift at 1350rpm, in 4th shift at 1250rpm and accelerate like there's an egg under your foot. Simple as that. Adjust slightly when going up hill or going down. If you have people behind you--give it a little more throttle and shift 200 rpm later--but never put the throttle all the way to the floor. You can also learn to shift quickly. The quicker you shift the less forward momentum you lose while accelerating.

The other thing you can do is become hypersensitive to when you are braking. Every time you touch the brake pedal your MPG goes down. Coast instead of brake where you can. Learn the traffic lights. Learn to anticipate what's happening in front of you. Don't drive directly behind people--go to one side of the lane so you can see what's going on 5-10 cars ahead. The single most effective mod you can do is simply adjust the nut behind the wheel.

I've gotten 70mpg in city driving.. but it is taxing to do so much EOC and not so great for the car, but it's kinda fun for the first half hour or so... then it becomes very tedious. But you really shouldn't need to turn the car off if you are aiming for just 50mpg. I thought people down south drove nice and slow and laid back?

[nowhhs]

Originally Posted by silversol

ok guys i am doing something seriously wrong! i just filled up and i got 35 mpg this tank!!!!! and that is driving very slow shifting a 2500! and some eoc! god what am i do in wrong!!!

I don't think you're doing anything wrong, I think there is probably a problem with your car. When I first got mine running after the swap, it wouldn't pass emissions because of a clogged cat and I drove it for a while just hammering it, shifting over 5k often, and the worst I could get was 37mpg. I'm not necessarily suggesting a clogged cat, I have no intention of trying to diagnose a problem via a forum, I'm just saying IMHO something is mechanically wrong. As most have said, you should be able to get mid 40s without trying.

[silversol]

Originally Posted by 1993CivicVX

What is it with 44mpg being the magic number for this car? So many VX owners are getting 44mpg. I hate to rub it in (okay, I don't) but for me I have to drive pretty carelessly to get 44mpg. Your description sounds like you should be getting 56-62mpg. But there is no reason to go above 2000RPM let alone 2500rpm. My car is bone stock minus a front spoiler/lip and I have no problem getting 50+mpg. The single biggest thing I think you can do to gain 10mpg would be the following: On flat ground in 1st gear shift at 1800RPMs, in 2nd gear shift at 1700rpm, in 3rd gear shift at 1350rpm, in 4th shift at 1250rpm and accelerate like there's an egg under your foot. Simple as that. Adjust slightly when going up hill or going down. If you have people behind you--give it a little more throttle and shift 200 rpm later--but never put the throttle all the way to the floor. You can also learn to shift quickly. The quicker you shift the less forward momentum you lose while accelerating.

The other thing you can do is become hypersensitive to when you are braking. Every time you touch the brake pedal your MPG goes down. Coast instead of brake where you can. Learn the traffic lights. Learn to anticipate what's happening in front of you. Don't drive directly behind people--go to one side of the lane so you can see what's going on 5-10 cars ahead. The single most effective mod you can do is simply adjust the nut behind the wheel.

I've gotten 70mpg in city driving.. but it is taxing to do so much EOC and not so great for the car, but it's kinda fun for the first half hour or so... then it becomes very tedious. But you really shouldn't need to turn the car off if you are aiming for just 50mpg. I thought people down south drove nice and slow and laid back?

you must have never been to atlanta. most of the drivers are idiots some dont have green cards and the fastest thing they drove before comeing to atlanta had hoves

[silversol]

Originally Posted by nowhhs

I don't think you're doing anything wrong, I think there is probably a problem with your car. When I first got mine running after the swap, it wouldn't pass emissions because of a clogged cat and I drove it for a while just hammering it, shifting over 5k often, and the worst I could get was 37mpg. I'm not necessarily suggesting a clogged cat, I have no intention of trying to diagnose a problem via a forum, I'm just saying IMHO something is mechanically wrong. As most have said, you should be able to get mid 40s without trying.

i know for 100% my cat is perfect. i had the same cat on my cx motor when i did emmisions 2 weeks ago. the inspecter told me he had never seen i civic of my year 92-95 pass with such low numbers! last night i did a compression test and all 4 were between 195-200. i also installed new oem ngk plugs. i also took out my 02 sensor and it had a little bit of black carbon and removed it with compressed air. the o2 sensor does not look to be old. but i am starting to think the o2 sensor might be the problem. but i really dont want to throw out the big money for the 02 and that not be the problem. do you guy know where i can get a new o2 sensor for a cheap price?

[thedaemon]

I get 44mpg all day and I shift at 2-3k. Yeah, Atlanta drivers are crazy. You will get run over if you are not at least driving 80mph. I made the mistake of doing the speed limit when I first drove through and people were honking, and yelling at me, trying to run me off the road. Very crazy.

[suspendedhatch]

Higher elevation in a town with low traffic, no hills, and few intersections would probably boost your mpg by 10mpg.

If you live at sea level with lots of traffic, ie southern California, that could explain why no matter what you can't achieve the same mpg that others brag about.

[PaleMelanesian]

Originally Posted by 1993CivicVX

What is it with 44mpg being the magic number for this car? So many VX owners are getting 44mpg. I hate to rub it in (okay, I don't) but for me I have to drive pretty carelessly to get 44mpg. Your description sounds like you should be getting 56-62mpg. But there is no reason to go above 2000RPM let alone 2500rpm. My car is bone stock minus a front spoiler/lip and I have no problem getting 50+mpg. The single biggest thing I think you can do to gain 10mpg would be the following: On flat ground in 1st gear shift at 1800RPMs, in 2nd gear shift at 1700rpm, in 3rd gear shift at 1350rpm, in 4th shift at 1250rpm and accelerate like there's an egg under your foot. Simple as that. Adjust slightly when going up hill or going down. If you have people behind you--give it a little more throttle and shift 200 rpm later--but never put the throttle all the way to the floor. You can also learn to shift quickly. The quicker you shift the less forward momentum you lose while accelerating.

The other thing you can do is become hypersensitive to when you are braking. Every time you touch the brake pedal your MPG goes down. Coast instead of brake where you can. Learn the traffic lights. Learn to anticipate what's happening in front of you. Don't drive directly behind people--go to one side of the lane so you can see what's going on 5-10 cars ahead. The single most effective mod you can do is simply adjust the nut behind the wheel.

I've gotten 70mpg in city driving.. but it is taxing to do so much EOC and not so great for the car, but it's kinda fun for the first half hour or so... then it becomes very tedious. But you really shouldn't need to turn the car off if you are aiming for just 50mpg. I thought people down south drove nice and slow and laid back?

Quoted again for emphasis. He's dead on.

And I disagree about the gearing / powerband thing. I rarely have my DX above 2000 rpm. It works just fine, and gives great mileage that way. Highway trips suck, running 2500+ rpm. I'm considering a CX/VX transmission swap.

[silversol]

i am thinking the hf trans might be a good idea. but does any one know if i can use the hf internals in a newer hydro transmission case?