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Ghosty
03-10-2008, 06:00 AM
I filled up the Celica for the wonderful price of $37 the other day. Gas was $3.19, and I was feeling frisky. Or it may just have been the fuel light glaring at me.

While I could go on and on about the price itself, what really bugged me was when I did the calculations and discovered that my humble Celica ST, with the 1.6 4AFE economy engine only got... wait for it...

24 mpg!!!

Now I'm no leadfoot, and a good hunk of it (at least 75 percent) was HIGHWAY DRIVING. At 70 mph and 3000rpms. Maybe a slight headwind. But I figure, I'd lost track of how many times I took the car on short trips to the campus and back. These were trips lasting less than 2 miles, and the car did not heat up, so naturally it would get a little rich.

Discounting the short cold-weather driving, it still doesn't make sense. The engine has just about 150k miles on it. Everything is well maintained, that is to say, we just did oil/filter/gasket/timing belt not 1k miles ago.

Here's what I'm wondering. The car has a short-ram, with the stock plumbing in place to funnel cold air onto the filter, and a straight pipe (muffler deleted). Now while logic would say "that's reduced restriction, that's better HP, Torque, and MPG," I'm starting to wonder if there isn't something more to it.

NA engines, economy engines, need some restriction to keep low-end power figures high. So, if I took out those restrictions like I did, it seems that cruising MPG would increase. But with intown driving, where there's a lot of stop-and-go, wouldn't the reduced power at the low end consequently reduce the intown MPG?

In other words, I'm going down the interstate doing 70 at 3k rpms, my engine is happy with no muffler and a short ram. But my engine is a tad starved for power when I'm taking off the red light up to 30mph, which reduces the MPG.

Does this sound right? Anyone heard of this? Am I losing my mind?

burnyd
03-10-2008, 06:17 AM
engine has just about 150k miles on it

okay end of discussion.

if youve done a tune up and you still get similar mpg your motor is tired.

Ghosty
03-10-2008, 06:36 AM
okay end of discussion.

if youve done a tune up and you still get similar mpg your motor is tired.

But I know a Toyota engine can last longer. Especially 4AFEs that are taken care of like mine. 200k reliable, efficient miles have been had on this motor.

Do you think this particular engine in my car just isn't one of "those" engines?

burnyd
03-10-2008, 07:09 AM
But I know a Toyota engine can last longer. Especially 4AFEs that are taken care of like mine. 200k reliable, efficient miles have been had on this motor.

Do you think this particular engine in my car just isn't one of "those" engines?


no it just has 150k on it. Plus in the winter time Gas tends to be alittle more richer so you will end up losing a few mpg... you should get better mileage but you should also be happy your car runs on a stock motor with that kind of mileage.... I meen A series motors are really economical motors I get 30-35 with mine lol and it has 185k on it... I just really dont know what to tell you if your getting that kind of fuel mileage with a complete tune up other than its getting tired.

supra97rx7
03-10-2008, 07:16 AM
I filled up the Celica for the wonderful price of $37 the other day. Gas was $3.19, and I was feeling frisky. Or it may just have been the fuel light glaring at me.

While I could go on and on about the price itself, what really bugged me was when I did the calculations and discovered that my humble Celica ST, with the 1.6 4AFE economy engine only got... wait for it...

24 mpg!!!

Now I'm no leadfoot, and a good hunk of it (at least 75 percent) was HIGHWAY DRIVING. At 70 mph and 3000rpms. Maybe a slight headwind. But I figure, I'd lost track of how many times I took the car on short trips to the campus and back. These were trips lasting less than 2 miles, and the car did not heat up, so naturally it would get a little rich.

Discounting the short cold-weather driving, it still doesn't make sense. The engine has just about 150k miles on it. Everything is well maintained, that is to say, we just did oil/filter/gasket/timing belt not 1k miles ago.

Here's what I'm wondering. The car has a short-ram, with the stock plumbing in place to funnel cold air onto the filter, and a straight pipe (muffler deleted). Now while logic would say "that's reduced restriction, that's better HP, Torque, and MPG," I'm starting to wonder if there isn't something more to it.

NA engines, economy engines, need some restriction to keep low-end power figures high. So, if I took out those restrictions like I did, it seems that cruising MPG would increase. But with intown driving, where there's a lot of stop-and-go, wouldn't the reduced power at the low end consequently reduce the intown MPG?

In other words, I'm going down the interstate doing 70 at 3k rpms, my engine is happy with no muffler and a short ram. But my engine is a tad starved for power when I'm taking off the red light up to 30mph, which reduces the MPG.

Does this sound right? Anyone heard of this? Am I losing my mind?

whaaaa
at 3k i'm at 60 mph :(

Luda
03-10-2008, 07:17 AM
208K on my 5s and i just got 29mpg combined city/highway

david in germany
03-10-2008, 07:43 AM
I have about 150k on my st also. I usually do about 33-35 mpg with the winter tires (195 55 15's) and average 35-38 MPG with the summer tires (185-65-14) (mostly 60-65 MPH) and a 44mile one way commute. I put the car almost back to stock (K&N drop in filter) and they do better on gas with stock intake pipeing.

Ghosty
03-10-2008, 05:00 PM
whaaaa
at 3k i'm at 60 mph :(

Don't know if you are manual or automatic; mine is an automatic. With overdrive, to be more precise, it's about 3,200 or 3,300 rpms @ 70mph.

If you're an auto doing 60mph at 3k, maybe your overdrive hasn't kicked in? Or maybe you have different ratios. I don't know.

Ghosty
03-10-2008, 05:01 PM
I have about 150k on my st also. I usually do about 33-35 mpg with the winter tires (195 55 15's) and average 35-38 MPG with the summer tires (185-65-14) (mostly 60-65 MPH) and a 44mile one way commute. I put the car almost back to stock (K&N drop in filter) and they do better on gas with stock intake pipeing.

Is your exhaust also stock, David?

I wish I got your mileage!!!

ciento44
03-10-2008, 05:55 PM
208K on my 5s and i just got 29mpg combined city/highway

What he said, but closer to 31mpg, and closer to 220k miles.

jlspec
03-10-2008, 06:37 PM
The best thing to do is turn it back to stock and see if that makes a different. Modifications like I/H/E should help to produce better MPG but some engines are already optimize for MPG. The 4A-FE I'm not sure but do give it a try. Put back the stock filter box along witha K&N drop in if you like. Also do put back the cat. The exhaust can be left alone as it won't make much difference on your car.

Ghosty
03-10-2008, 07:01 PM
The best thing to do is turn it back to stock and see if that makes a different. Modifications like I/H/E should help to produce better MPG but some engines are already optimize for MPG. The 4A-FE I'm not sure but do give it a try. Put back the stock filter box along witha K&N drop in if you like. Also do put back the cat. The exhaust can be left alone as it won't make much difference on your car.

That seems like it would be the best thing to do.

I've heard the argument before that engines like the FE-headed engines, namely the 4AFE, are very highly tuned from Toyota. They are so well tuned for economy that there really isn't much that can be done to improve mileage or power. Just keep the engine healthy seems to be the best thing.

I might be searching for my stock airbox soon. But in the meantime, I should probably go get a distributor cap and rotor. Don't know when those were changed last. Maybe an O2 sensor.

Oh, and I'll request that the post gets moved to Maintenance and Troubleshooting if it turns into one of those posts (which it looks like it is becoming). I appreciate all the help, though! 24 mpg on a 4AFE sucks balls!

Lonestag
03-10-2008, 07:52 PM
Well, I've heard for every 5mph over 55mph you lose about a mpg. So at 70mph you would be losing 3mpg just right there.

I'm sure you have checked all the other little things that normally are associated with gas mileage (Tires, plugs, wires, ect...) so I won't go on about that stuff.

3k RPMs does seem a bit high though, if you have the patiance, try going around 55mph for a tank, and see how much better you do.

Toy_Celi
03-10-2008, 08:36 PM
I filled up the Celica for the wonderful price of $37 the other day. Gas was $3.19, and I was feeling frisky. Or it may just have been the fuel light glaring at me.

While I could go on and on about the price itself, what really bugged me was when I did the calculations and discovered that my humble Celica ST, with the 1.6 4AFE economy engine only got... wait for it...

24 mpg!!!

Now I'm no leadfoot, and a good hunk of it (at least 75 percent) was HIGHWAY DRIVING. At 70 mph and 3000rpms. Maybe a slight headwind. But I figure, I'd lost track of how many times I took the car on short trips to the campus and back. These were trips lasting less than 2 miles, and the car did not heat up, so naturally it would get a little rich.

Discounting the short cold-weather driving, it still doesn't make sense. The engine has just about 150k miles on it. Everything is well maintained, that is to say, we just did oil/filter/gasket/timing belt not 1k miles ago.

Here's what I'm wondering. The car has a short-ram, with the stock plumbing in place to funnel cold air onto the filter, and a straight pipe (muffler deleted). Now while logic would say "that's reduced restriction, that's better HP, Torque, and MPG," I'm starting to wonder if there isn't something more to it.

NA engines, economy engines, need some restriction to keep low-end power figures high. So, if I took out those restrictions like I did, it seems that cruising MPG would increase. But with intown driving, where there's a lot of stop-and-go, wouldn't the reduced power at the low end consequently reduce the intown MPG?

In other words, I'm going down the interstate doing 70 at 3k rpms, my engine is happy with no muffler and a short ram. But my engine is a tad starved for power when I'm taking off the red light up to 30mph, which reduces the MPG.

Does this sound right? Anyone heard of this? Am I losing my mind?

Id put the mufflers back on... it is the restriction, you need backpressure, without it you get valve play, and that means more/less air, more/less exhaust and more/less gas... my SUV did the same thing, but the sound is well worth it, better than that stock muffler!

david in germany
03-10-2008, 08:52 PM
Is your exhaust also stock, David?

I wish I got your mileage!!!
Stock manifold that I dremeled smooth inside and stock from there back to a walker stock replacement muffler.

Ghosty
03-11-2008, 02:45 AM
Ok everybody... Took a look at Edmunds.com and they told me the EPA estimates for my ST are: 25mpg city/ 33 mpg highway. For a manual, the figures increase to 28/ city but the highway is the same. Here's a short list of thing's I've brainstormed that could have contributed to the gas mileage:

- 75 percent highway mileage at 70mph, 3k rpms (lonestang estimates 3mpg loss and that seems about right)
- High winds, headwind on a 100 mi, 70mph highway trip.
- The same 100 mi trip was loaded down with gear (one desktop computer, a week's worth of clothes, and probably 20lbs misc. items. I weigh 130-ish)
- 25 percent driven in short trips, with temperatures mostly between 20 and 30 degrees. On a third to a half of these trips, the engine does not warm up completely or reaches full temp for only a short period.

So probably there were a lot of factors contributing to a miserable gas mileage. I'm looking into finer details now to remedy the problem, because I believe better mileage can be achieved.

Asked my dad when the last time was that he changed the distributor cap and rotor, and he said something like 5 years ago...when I first got the car. Approximately 50,000 miles ago. Went to NAPA, got a NAPA rotor for approx $4, then went over to Advance Auto and got a distributor cap + spark plug wires for about $35.

Took off the old distributor cap and looked inside. It looked fairly worn, with some oxidation. Not terrible wear, but otherwise unremarkable. Then took off the rotor and inspected that; there was a caking of oxidation on it, which was remarkable. Fit on the NAPA rotor (was kind of concerned at first because it wasn't the snuggest of fits, not as snug as the previous rotor, but I figured the cap would secure it in place), fit on the distributor cap, plugged in the wires... 4 was closest followed by 3, 2 and 1. Started her up, and immediately noticed a smoother idle.

I'll keep updates in this thread how the mileage improves. I'm expecting to put 200 mi on her tomorrow. If I don't notice much of a difference, I'm going to replace these in the following order:

1) OEM Toyota Fuel cap
2) O2 sensor

And I ran a rough calculation on the economy of replacing the distributor cap and rotor. If I gain one MPG, I will need about 12,000 miles for the distributor cap and rotor to pay for themselves. This might increase or increase depending on the price of gas.

Lonestag
03-11-2008, 03:00 AM
Man, watch out for those 3rd party plug wires. I had them on my celi for less then a year and I had to have them replaced becasue they were shorting out in mulitple areas.

jlspec
03-11-2008, 03:05 AM
Usually when changing those componenets it will also help improve power. 24 mpg is really bad for the 4A-FE motor. My alltrac I do about 20-22 mpg doing half street and freeway driving.

Ghosty
03-11-2008, 03:42 AM
Man, watch out for those 3rd party plug wires. I had them on my celi for less then a year and I had to have them replaced becasue they were shorting out in mulitple areas.

How did you tell they were shorting out? Were there misfires?

MrWOT
03-11-2008, 05:00 AM
Uh, lowering pumping losses will equate to an increase in mpg, if the same ammount of air is ingested, but if you're increasing mass (intake), you WILL need more fuel for the same ratio to be maintained. :squint:

david in germany
03-11-2008, 06:37 AM
Ok what I have learned with my ST Run only OEM cap and wires ,it will cost a bit more but the quality is 10x better than anything else out there for the 4a-fe. DO NOT RUN BOSCH PLUGS! run the proper NGK for the car and it will love you. Run at least 98 octain gas.
For highway driving keep it about 60-63 mph. City driving, do not excelerate in high rpms.
I pulled 33 mpg on my fill up yesterday (with a good bit of city driving)
And of course keep the reccomended air pressure in the tires!

KoreanJoey
03-11-2008, 07:15 AM
YES USE OEM TOYOTA!

God why you guys buy crap from NAPA on something as important as your electrical systems I have no idea...

Lonestag
03-11-2008, 03:17 PM
Yeah, the wire from the ingitor to the distributer would jump a spark to my cold air short ram intake and kill the motor when reving. (that was an interesting problem, and hard to diagnose).
The other wire just went plane bad, I took it out while the motor was running and you could see where it was shorting out on itself. You couldn't even get it to jump a spark.

Toy_Celi
03-11-2008, 08:11 PM
Man, watch out for those 3rd party plug wires. I had them on my celi for less then a year and I had to have them replaced becasue they were shorting out in mulitple areas.

I agree... i use Autolite or OEM ones......

Ghosty
03-12-2008, 05:30 AM
YES USE OEM TOYOTA!

God why you guys buy crap from NAPA on something as important as your electrical systems I have no idea...

Because I'm a poor as mutherfucker and I don't know no betters!

I just bought the damn thing... how much is OEM going to run me?

KoreanJoey
03-12-2008, 07:01 AM
I agree... i use Autolite or OEM ones......

Autolite is crap too.

AGAIN OEM TOYOTA

Cable set, celica, w/o turbo, st 90-92 $64.76
www.1sttoyotaparts.com

Well worth it.

You pay to not have your car run like poo.

Ghosty
03-12-2008, 07:07 AM
I'll take your word for it and buy another cap and rotor.

Never realized after market was such crap stuff. Figures though, get what you pay for. And I didn't pay much, so I guess I didn't get much. But live and learn, right?

KoreanJoey
03-12-2008, 07:12 AM
You sure do. There are some decent aftermarket companies but those are expensive too. Magnecore makes decent stuff from what I've heard.

cs363
03-12-2008, 11:03 AM
http://cgi.ebay.com/ebaymotors/MR2-IGNITION-KIT-WIRES-CAP-ROTOR-TURBO-3SGTE-93-95_W0QQcmdZViewItemQQcategoryZ33692QQihZ022QQitemZ 350035175283QQrdZ1QQsspagenameZWDVW

I bought one of these kits from this seller - considering what you get the price is good, cheaper than I could have got them here in NZ including shipping! It's always worth checking genuine as they aren't always as expensive as you might think and you can't beat the quality.

oldschoolst165
03-12-2008, 11:31 AM
You may want to check your O2 sensor when they get tired the computer thinks the mixture is lean and adds fuel. If you need to know how to check it just post a reply.

KoreanJoey
03-12-2008, 01:24 PM
http://cgi.ebay.com/ebaymotors/MR2-IGNITION-KIT-WIRES-CAP-ROTOR-TURBO-3SGTE-93-95_W0QQcmdZViewItemQQcategoryZ33692QQihZ022QQitemZ 350035175283QQrdZ1QQsspagenameZWDVW

I bought one of these kits from this seller - considering what you get the price is good, cheaper than I could have got them here in NZ including shipping! It's always worth checking genuine as they aren't always as expensive as you might think and you can't beat the quality.

Nice, but unfortunately that's for the wrong car.

cs363
03-12-2008, 07:18 PM
Nice, but unfortunately that's for the wrong car.

Wrong for his car yes, sorry I should have made that clear :)
I was just trying to show that OEM is not always expensive.
And even though my car is a 91 GT4 this is actually the kit that fitted mine.

zak062
03-12-2008, 07:26 PM
I have the same problem. Mines a 91 gts auto and i get 19mpg city. I rarly go on the highway. EVERYTHING is stock in the car and i just re-sealed the engine with a new cap, plugs, wire, air filter, oil filer, fuel filter, etc...

Toy_Celi
03-12-2008, 08:20 PM
Autolite is crap too.

AGAIN OEM TOYOTA

Cable set, celica, w/o turbo, st 90-92 $64.76
www.1sttoyotaparts.com (http://www.1sttoyotaparts.com/)

Well worth it.

You pay to not have your car run like poo.


Do you only use OEM, or have you ever strayed for the good deals?? The SUV i have ran fine with a cracked cap and 5 year old Autolite wires, so i thought they were pretty good....

What about those pulseplugs, would that make any difference in the wiring to cause better mpg? They claim it does, but i doubt it...

Ghosty
03-12-2008, 09:40 PM
Wrong for his car yes, sorry I should have made that clear :)
I was just trying to show that OEM is not always expensive.
And even though my car is a 91 GT4 this is actually the kit that fitted mine.

NAPA wanted $81 for a cap and plugs. I believe they are Bosch, though I'm not sure. Would they work better and last longer? Maybe. But it makes more sense to spend $61 on an OEM than $81 on an after market to me.

KoreanJoey
03-13-2008, 02:43 AM
Ok by an large domestic cars are fine w/ Bosch and the like, often Bosch makes the OEM equipment for lots of domestic vehicles.

My experience is that OEM Toyota quality beats most aftermarket products and I'm not willing to sacrifice reliability for a few bucks.

supra97rx7
03-13-2008, 03:59 AM
Don't know if you are manual or automatic; mine is an automatic. With overdrive, to be more precise, it's about 3,200 or 3,300 rpms @ 70mph.

If you're an auto doing 60mph at 3k, maybe your overdrive hasn't kicked in? Or maybe you have different ratios. I don't know.

oh. then it's about the same. mine's manual, 3.3-3.5k at 70

G.W
03-13-2008, 05:02 AM
Quote:
Originally Posted by Ghosty
Don't know if you are manual or automatic; mine is an automatic. With overdrive, to be more precise, it's about 3,200 or 3,300 rpms @ 70mph.

If you're an auto doing 60mph at 3k, maybe your overdrive hasn't kicked in? Or maybe you have different ratios. I don't know.


oh. then it's about the same. mine's manual, 3.3-3.5k at 70.


No mater what, how you drive your car has the most affect on mpg. Shift @ 2800 to 3000rpms, run @ low @ rpm when possible and 65 mph max (93gt coupe 3s/5sfe 35city 45hwy 89oct)

supra97rx7
03-13-2008, 05:27 AM
Quote:
Originally Posted by Ghosty
Don't know if you are manual or automatic; mine is an automatic. With overdrive, to be more precise, it's about 3,200 or 3,300 rpms @ 70mph.

If you're an auto doing 60mph at 3k, maybe your overdrive hasn't kicked in? Or maybe you have different ratios. I don't know.


oh. then it's about the same. mine's manual, 3.3-3.5k at 70.


No mater what, how you drive your car has the most affect on mpg. Shift @ 2800 to 3000rpms, run @ low @ rpm when possible and 65 mph max (93gt coupe 3s/5sfe 35city 45hwy 89oct)
you'll find it interesting that i've gone a tank of gas shifting at 3000rpms, and i got about 220 on that tank. the next tank, i shifted around 4500rpms, and got 240. same mix of highway and city, so probably just a difference of waiting in traffic/stop lights.

but gas mileage has been a problem since i've had the celica. it used to idle high all the time, and i discovered it was running cold so i changed the thermostat and that was the problem. so far though, mileage has not increased.

until i can figure out what it is that's not functioning properly, i can drive like a madman. YAY
terrible gas mileage. not YAY.

Ghosty
03-13-2008, 05:46 AM
you'll find it interesting that i've gone a tank of gas shifting at 3000rpms, and i got about 220 on that tank. the next tank, i shifted around 4500rpms, and got 240.

You say you got such-and-such mileage on one tank, but measuring it based on tank capacity isn't terribly accurate. How can you tell how much is left in the tank, and how much gas do you fill it with?

The best method is drive until you need to fill up, fill it up until the pump shuts you off. Then when you need another fix, go back to the same pump, repeat, and do the calculations with your trip odometer and the number of gallons it reads on the pump. Again, make sure you fill to the top.

Even that isn't perfect, but it's close. Just a tenth of a gallon difference (one decimal point) can throw off your figures. This also doesn't figure in the fuel density as it fluctuates with temperature (when you fill it up on a 20 degree day, you are putting more fuel in your tank than on a 75 degree day).

supra97rx7
03-13-2008, 05:55 AM
You say you got such-and-such mileage on one tank, but measuring it based on tank capacity isn't terribly accurate. How can you tell how much is left in the tank, and how much gas do you fill it with?

The best method is drive until you need to fill up, fill it up until the pump shuts you off. Then when you need another fix, go back to the same pump, repeat, and do the calculations with your trip odometer and the number of gallons it reads on the pump. Again, make sure you fill to the top.

Even that isn't perfect, but it's close. Just a tenth of a gallon difference (one decimal point) can throw off your figures. This also doesn't figure in the fuel density as it fluctuates with temperature (when you fill it up on a 20 degree day, you are putting more fuel in your tank than on a 75 degree day).
i can see that, and you're right. regardless, i'm getting terrible mileage. i can't imagine that nothing's wrong - i've never gotten above 240. well, maybe a little bit, like 245 or so.
anyway, i'm not exactly sure what to check next. O2 sensor probably.

Ghosty
03-13-2008, 06:22 AM
i can see that, and you're right. regardless, i'm getting terrible mileage. i can't imagine that nothing's wrong - i've never gotten above 240. well, maybe a little bit, like 245 or so.
anyway, i'm not exactly sure what to check next. O2 sensor probably.

Since changing my distributor cap, wires and rotor, I've noticed a small bump in mileage. It was an extremely simple and straightforward process, learned how to do it with some videos on the intarwebz. The total OEM cost is around $70.

Basically, it's all about maintenance. Changing oil and filter, monitoring and changing plugs, monitoring air pressure in tires and changing them/ aligning them as needed, timing belt is a big one too. Besides that, what I mentioned above with the distributor, and you're right about the O2 sensor. Those do go bad after a while, something like 50k miles. Another odd part is a gas cap. Yes, those need replaced too. Just not that often. It will help seal the tank and prevent vapor leakage.

If you want to go the extra mile, put the car on jacks and take a look around the fuel tank. Feel the lines coming out of it, any wetness? You'll find out real quick if you have a leak. My original tank suffered a slow leak... then it suddenly developed into a massive leak. The problem was pads they put on to keep the tank from rubbing on the bolts that hold the passenger's seatbelt to the chassis. One of the pads came loose, the bolt rubbed the tank until it made a nice lil' hole. Gas leaked down the control arms, drip drip. Also inspect the fuel filler neck while you're down there--- those have a strong tendency to rust and vent gas. Watch for that, guys. It does happen.

As stated before, you want to keep things as close to OEM spec as possible. But you can improve the original design in small ways. For instance, getting a K&N high-flo filter for your stock airbox. There is a 4AFE header made by Pacemaker that may or maynot increase gas mileage. Experiment with highflo-cats, performance mufflers -- but mileage may vary. Take it all with a grain of salt.... how much gas is it going to take to make up that $300 expense?

Also, how much stuff do you keep in your car? Do you keep a large book of CDs, an emergency kit, snowfighting gear, etc? Bring only what you need. And yes, you should keep your spare tire. That's essential.

... am I forgetting anything, guys?

KoreanJoey
03-13-2008, 06:28 AM
Or you can bite the bullet and do a Gen 3 3SGE swap. :)

36.8MPG, hammer down, mixed driving.

Ghosty
03-13-2008, 07:00 AM
Or you can bite the bullet and do a Gen 3 3SGE swap. :)

36.8MPG, hammer down, mixed driving.

I still don't know how you manage that.

Is it because the head has ultra-efficient flow, and the compression ratio is so high?

KoreanJoey
03-13-2008, 07:04 AM
Probably more the ECU being smarter...

Ghosty
03-13-2008, 06:12 PM
Probably more the ECU being smarter...

Is that the factory ECU you're using? Is it re-flashed? Or do you use a stand-alone?

Unarmed
03-16-2008, 04:41 AM
I get a guestimated 30-35 mpg 50/50 city highway. 3k-3.4k rpms. mildly spirited driving. autolite plugs, no-name cap (old one somehow tore off the top bolt) ,dont know what kinda rotor, NGK 92-93 plug wires (they do fit on the older motors, the seal is exactly the same, they just added extra rubber for cosmetic effect (to give it that square shape) in 92. go little 5s go.

G.W
03-16-2008, 05:37 PM
That was my ^^setup^^ but I did notice better mileage after a timing belt job.

VikingJZ
03-16-2008, 07:30 PM
I have ORIGINAL plug wires and cap (rotor is not that old) and I get 23 under normal conditions. Thats already better than the EPA estimate and I track mileage like a hawk. I consistently get 23 unless I rag on it, even better on the highway. After a tune up I see no reason for me to not attain high 20's and possibly 30's if I attempt to hypermile (*maybe more if I get good at it)

Blackcloud
03-16-2008, 07:52 PM
:laugh:

only $37.. i put in $75 and dont even get a full tank

VikingJZ
03-16-2008, 08:36 PM
You can use an aftermarket rotor. Cap, wires, and plugs are what you need to worry about.

AutoZone CARRIES Denso plugs. Not sure about Denso other stuff.

Ghosty
03-16-2008, 09:20 PM
The first real measurable results are in...
With 50/50 highway/city driving, with a load of 2 passengers on the 70mph/2.8k rpm highway driving portion, I was able to achieve...

29 mpg

Not bad in my opinion, this is better than stock expectations. I still have some things that I can do to improve mileage as well, such as cleaning my 8-month-old K&N filter and getting a new gas cap. And, of course, drive slower and with less passengers. So, I have every reason to believe this could be improved still, and perhaps my modifications haven't made a terrible impact on mileage.

I drive more conservatively now in the city, just letting the car accelerate as it wants to in the 2.2-.4k range and letting it shift as it pleases. I'm especially cautious on a cold engine, making sure to go easy on accelerating until it warms up so it doesn't dump as much fuel.

One thing I'm interested in looking at is a DIY diffuser for the car to reduce drag, and therefore improve gas mileage. If you look at the way most cars are designed, the rear bumper hangs down a great deal and acts as sort of a parachute that grabs air exiting the underside of the chassis. The diffuser would block this off and create a smoother surface for the air to travel. Air channels could also be integrated into the design.

The neat thing about the diffuser is that it can be made from many different kinds of materials. It doesn't have to be especially resilient or heavy. Plastic, fiberglass and aluminum could all be used. The hardest part is making a template to cut it, and drilling the appropriate holes to attach the thing.

I might post up some pages from a book on racecar aero theory later to show exactly what I mean. They give some pretty good advice on dimensions and such in this book.

cs363
03-16-2008, 10:21 PM
Ok by an large domestic cars are fine w/ Bosch and the like, often Bosch makes the OEM equipment for lots of domestic vehicles.

My experience is that OEM Toyota quality beats most aftermarket products and I'm not willing to sacrifice reliability for a few bucks.


I'll second that! :bigthumbu

KoreanJoey
03-17-2008, 05:24 AM
Is that the factory ECU you're using? Is it re-flashed? Or do you use a stand-alone?

Factory Gen 3. :)

And yes if you got with aftermarket, you should be ok with JDM aftermarket equipment:
NGK, Denso, SARD