It's time to push the car to it's limits.

[Compaq888]

I've been averaging 28mpg. But now I'm pulling out all the stops. I have done some research and at least 8 garage members have their tires inflated more than the max cold pressure. I will now inflate my tires to 55psi.

-I have turned off all my electronics. Only thing will be used is cruise control.

-Car will NOT coast in neutral or with engine off. I already blew my rack&pinion, I don't need any problems.

-Converted all my Brake lights to LED's since it effects fuel consumption. My license plate bulbs are now LED.

-I have added Rear Belly pan, and 2 Front undertrays.

-Using synthetic

-Using NGK V power spark plugs

-Using AutoRX engine cleaner.

Anymore tips to break past 30mpg mixed???
I don't plan to use any other oil viscosity and I already did a tranny flush, alignment too.

I also want to join the hypermiler bandwagon.

[brick]

Breaking 30mpg will be all about how you drive the car since you're pretty maxed-out on mods. Do you know about all of the techniques that krousdb uses to break 60s in his Del Sol? Use them all, with the exception of engine-off coasting since you don't want to. That means driving with the load (let the car speed up as you head down hill and then trade that kinetic energy for potential as you come up the next, reducing speed on the way up.) If you are on the freeway, try to keep your speed around 60 or less if possible. Anticipate lights and traffic so that you don't have to use your brakes. Accelerate as gently as possible and keep the revs very low. Drafting is a touchy thing, so that's up to you. Personally I don't touch anything but a long straight draft or the occasional side draft if I get lucky. Don't want to bang up my car! Finally, remember that short trips on a cold engine are the real MPG killer. String those trips together if at all possible.

Finally, do you have a ScanGauge? That feedback is worth a mint! Having instant fuel economy right in front of you will help modify driving habits for the best results.

I've seen low to mid 30s on the highway with my girlfriends AWD Volvo using nothing but feedback from the trip computer, gentle acceleration, DWL, and low speeds. Your Altima ought to be cake compared to that heavy beast. Be religious about your driving and you will be over 30mpg in no time. Probably much higher.

[Compaq888]

I don't need a scangauge. My car follows one rule. The lower the rpm the better the fuel economy.

My altima is heavy. I have an Iron block which weighs more than most v6/inline 6 engines.

btw I have 4 cylender.

the only thing that's different from my 32-33mpg freeway runs is more pressure in the tires, Auto-rx, LED's, and less electronic stuff used.

[zpiloto]

I think 10-15 over max rated is a good target to look at. My max is 35 and I am currently running 50/45. I thinking of going back to 45/45 because the ride is harsh on rough roads. I did not notice any change in FE when I went to 50. AC a killer and if you travel the same routes and know the light patterns you can turn off the engine at the long ones and transmission in neutral on the rest if you're not already doing it. I lose almost 1 MPG a minute on the trip MPG when sitting at a light. Try to stay away from the track for a tank

[Compaq888]

I couldn't get the tires up to 50psi. After 46-47psi the gauge gets very inaccurate. My max cold tire pressure is 44psi. I put all the tires at 46psi. I can't get another gauge right now because I spent the money I don't even have on a rack&pinion and even that was half assed. One part is missing.

[brick]

Originally Posted by Compaq888

I don't need a scangauge. My car follows one rule. The lower the rpm the better the fuel economy.

In general that's how it works. But you would be amazed at what subtle changes throttle position do to instantaneous fuel economy. The reason feedback is important is because it is possible to be driving along at what you think is steady state, but you are actually accelerating imperceptibly. Backing off of the throttle to achieve true steady-state (or even imperceptible deceleration) can make a difference to the tune of several MPG. You don't need a ScanGauge, I'm just saying it would really help you to fine-tune what the right foot is doing.

[Compaq888]

If I had the money I would buy it. I just spent $500 to buy a replacement pinion&rack and have it installed.

I could totally see a 1mpg improvement with the scangauge but i basically covered all my bases. When I accelarate slow and drive 65mph I get the best mpg. If I go 55mph I get half a mile more per gallon.

[molecule]

i recommend a good catchcan setup...
since reburn was introduced engines send all the oily gunk from crankcase heating back directly into the intake to be burned in the engine...
some cars produce significantly more gunk and hampers performance
it doesn't belong in the engine...it doesn't belong on the roads either...
all cars used to just dump emissions to the street
maybe you are too young to remember all the black lines down the center of every lane in america...

[Sludgy]

What if you hit a pothole, blow out a tire and kill someone? Who is liable?

Nissan? Michelin (or whoever? Gassavers? Matt Timion?

All I know is that it's not ME. I hereby advise against overinflation.

[Compaq888]

I have a catch can setup just need to install it. Since nissan put the PVC in a almost inaccessable space I'll just install the PVC catch can when I'm replacing the PVC.

[Compaq888]

Originally Posted by Sludgy

What if you hit a pothole, blow out a tire and kill someone? Who is liable?

Nissan? Michelin (or whoever? Gassavers? Matt Timion?

All I know is that it's not ME. I hereby advise against overinflation.

Relax my tire pressure is the max cold pressure.

[Matt Timion]

Originally Posted by Sludgy

What if you hit a pothole, blow out a tire and kill someone? Who is liable?

Nissan? Michelin (or whoever? Gassavers? Matt Timion?

All I know is that it's not ME. I hereby advise against overinflation.

I know that these tires are set up to go way beyond their limits, but I still don't overinflate for this reason. I've had enough problems with tires in my time and the last thing I want is another flat.

[JanGeo]

Hey what are you guys doing with the sludge that fills your catch cans?? reintroducing it back into the environment?

[SVOboy]

Hey what are you guys doing with the sludge that fills your catch cans?? reintroducing it back into the environment?

Toss it in with the oil recycling I'll say.

[krousdb]

Originally Posted by Compaq888

I could totally see a 1mpg improvement with the scangauge but i basically covered all my bases.

What Brick has said is right on. Those techniques are key. I have seen a 10 MPG improvement by using the SuperMID.

Originally Posted by Compaq888

When I accelarate slow and drive 65mph I get the best mpg. If I go 55mph I get half a mile more per gallon.

That is very surprising to me. 55 vs 65 should get you much more than 1/2 MPG. Maybe you should try it again to make sure.

[kickflipjr]

By watching the supermid or scangauge do learn to adapt to efficient driving? krousdb (and whoever else uses a mpg tracker) do you think you would get nearly the same mpg without it?


I try to drive as efficently as posible, but it is hard for me to beat 35mpg in mixed conditions. I do need an alignment fairly bad (the car tracks to the right on the highway after a 1/10 mile).

[krousdb]

Originally Posted by kickflipjr

By watching the supermid or scangauge do learn to adapt to efficient driving? krousdb (and whoever else uses a mpg tracker) do you think you would get nearly the same mpg without it?

A tool like the SuperMID or Scangauge will teach you how to drive that specific car as efficiently as possible. But what you learn will stay with you forever. Today, if I removed the SuperMID, I would lose only a small amount of the increase that I gained from it.

Still dont know my true potential yet because I have not yet peaked. But when I do peak I would consider lending it to another OBD1 gassavers member who would be interested in trying it out. Matt????

I was thinking that there may be some value in having a community Scangauge and/or SuperMID that would be paid for by money pooled by Gassaver members. It would be passed from one member to the next for a tank or two to see how much improvement can be gained from it. Yes, something like this would require that we trust one another but it is less risky if you are chipping in $5 or $10 vs $150 for something that you dont know whether or not it is worth it.

Or maybe it is just a stupid idea. The point is that until you get one, you will never know how much you really need one.

[SVOboy]

Yeh, I def plan on loaning my out once I get my **** covered. When I meet jared to get his stock d16z6 header for testing I'll return the header with it to him, and we can just meet up at a later date or something,

Makes perfect sense to me!

[MetroMPG]

Originally Posted by Compaq888

I could totally see a 1mpg improvement with the scangauge but i basically covered all my bases.

i used to think i had covered all my bases. but you don't know what you don't know (by that i mean the royal you, not you specifically compaq).

When I accelarate slow and drive 65mph I get the best mpg. If I go 55mph I get half a mile more per gallon.

no offense, but i seriously doubt that. and guess what? if you had a scangauge, you'd know for sure...

a simple scangauge trial i did yesterday - MPG at increasing speed intervals, flat road, no wind, warm (60 ish), cruise control, top gear:

69 mpg (US) @ 65 km/h (40.4 mph)
62 mpg (US) @ 75 km/h (46.6 mph)
55 mpg (US) @ 85 km/h (52.8 mph)

you see where this is going, right?

after basic maintenance, i wouldn't spend a penny more on mods until i had FE instrumentation like a superMID or a scangauge.

aside from helping you evaluate FE mods and driving technique, it's also simply a constant reminder that keeps your mind on the task at hand.

[SVOboy]

after basic maintenance, i wouldn't spend a penny more on mods until i had FE instrumentation like a superMID or a scangauge.

Indeed, I have forstalled all mods while waiting for my superMID in the mail!

[MetroMPG]

Originally Posted by krousdb

I was thinking that there may be some value in having a community Scangauge and/or SuperMID that would be paid for by money pooled by Gassaver members.

awesome idea. i'd chip in to the pool to help out.

one guy on the EV list "rents" an expensive set of electrical cable crimping tools to other EV enthusiasts. the "rental fee" is the actual purchase price of the tools + shipping. he refunds the purchase price when you return his tools.

[JanGeo]

Originally Posted by MetroMPG

69 mpg (US) @ 65 km/h (40.4 mph)
62 mpg (US) @ 75 km/h (46.6 mph)
55 mpg (US) @ 85 km/h (52.8 mph)

How about continuing the measurements to 55 45 35 km/h seems to be a very interesting progression and I wonder if it changes slope as you go slower.

[SVOboy]

I believe he's already posted that info in the experiments section.

[MetroMPG]

Originally Posted by SVOboy

I believe he's already posted that info in the experiments section.

maybe you're thinking of the constant speed, different gears experiment.

jangeo, i didn't go below 65 because the engine really isn't happy in top gear below there. incidentally, you're right - i believe my mpg starts to decline again (at slower constant speeds) somewhere between 60-65 km/h in 5th. the curve changes.

i'll eventually do a proper test of this with a greater range (i suppose i'll lug the engine at 55 km/h for the sake of science, plus i'll go much higher for fun). i want to find the car's "sweet" spot, and this is one way to do it. i believe it's right around 65 km/h.

[SVOboy]

Yes, I was thinking of the different gears test, sorry for the confusion!

[Compaq888]

like I said before I have always seen that the lower rpm I go the more fuel I save. My OD gear starts at 37mph. If I go 37mph I'll be at 1250rpm. Which should get me the best mpg due to several factors.
One is I'm going in the highest possible gear. Then I'm in the lowest possible rpm. And also there is less wind resistence than going higher speed.

So for me the faster I go the more fuel I spend.

[molecule]

i would drive 55 if i thought it was safe...
on most highways...that brings considerable traffic up on your *** in a hurry...
i always could get better mileage going 55...but not enough to risk my life...
63.5mph has been the speed for my career...
it allows 'idiot' traffic to flow around you more safely
55 is a hazard in todays world

[Compaq888]

Originally Posted by eigerzoom

i would drive 55 if i thought it was safe...
on most highways...that brings considerable traffic up on your *** in a hurry...
i always could get better mileage going 55...but not enough to risk my life...
63.5mph has been the speed for my career...
it allows 'idiot' traffic to flow around you more safely
55 is a hazard in todays world

too true

[mtbiker278]

I saw a news story a couple of weeks ago where they covered how to save gas. One of their tips was to drive the speed limit. Makes sense, until you notice that you're driving on the belyway and the speed limit is 55. During their story a tractor trailer almost rear-ended them as they were going 55. I'm pretty sure that sent a clear message to whoever was watching.

[Compaq888]

you should see the thread I made in the off topic of people driving the speed limit. There was a hit and run involved.