tc

hypermiling - coasting downhill, draafting, shutting off the motor while stopped ... some of these guys are getting HUGE MPG numbers

Red_Chili

I got over 19mpg in my flying brick with 35 MT/Rs and the top rolled up, from Buena Vista to Littleton, going over Kenosha Pass and fighting a headwind in South Park, following some of their guidelines. (Driving with the motor off is not safe...)

I got passed a fair bit, but I just smiled.

STEvil

tc - yes

tulsa - thanks

kiwi - yup

herb - The fan is not for cooling purposes.




Might help if I didnt have a slushbox too I think lol

n16ht5

i have been getting 22.5mpg going to work everyday...

94 5spd 4.10s and 33x1250s


i use little brakes and little gas

Herblenny

I understand that you are not using the fan for "cooling" ICs.. I don't think you quite understand the concept of turbo(s). Turbos are in constant spin and they are always producing air flow. If turbo compressor wheels stop, it would have to go from 0 rpm to thousands of RPM, which will make your car VERY unresponsive! The fan you are stating will be useless and will hinder flow if you are boosting at high level. Just think about it, your fan will have a motor and blades.. which turbos will definitely out flow and now your fan and motor will in hindering the flow. Also you have to remember that the fan you are talking about is pulling HOT air from the turbo, as if you try to plumb fresh air in along with turbo system, you will have even more intricate system as you need one way valve of somesort as boost will defintely leak out when turbos kick in. This so call fan you might be talking about reminds me of the gas saving scam those tornado guys talked about.

Bottomline, turbo(s) will constantly produce some air. BOV and wastegate will control the spooling and compression of air. Also, the engine will try to suck in air at idle and compressed air will affect the idle otherwise. Hence BOVs to relieve pressure, otherwise, you'll have issues in many levels.

I say this to those who want to save gas with rotary engine cars.. If you want to save gas on a sport car, then its better you go buy an econo.... especially turbo charged cars. There are so many people think just slapping one a turbo will produce reliable power.. These days, its all about picking the right size for right application and... TUNING!

Skinsfan6

If you're still looking for more torque, a long tube header into 2.5" exhaust out the back works very well. I put a pacesetter header on my 4runner and ran a 2.5" cat and 2.5" muffler out the back. Just make sure you use a real muffler with plenty of backpressure and not a glasspack. 22REs like lots of backpressure. I gained enough torque and acceleration that I could definitely feel it when driving. It would get up and go quite a bit quicker and pulled better up until I would shift around 3500.

I would imagine an electric fan would help a lot too, as a such a little engine pushing the clutch fan the majority of the time can't be completely necessary.

abecedarian

I've finally decided that if you want good mileage and performance, you'll need to go with a constant speed engine powering a three-phase A/C generator coupled to an appropriate motor-speed controller, lithium-ion storage batteries and electric motors for the drive line.
Maybe you can get Tesla Motors to collaborate.
If you can get a good generator based on a Wankel type engine, you just might have a good thing going.

(can't find appropriate emoticon... still looking though)

Herblenny

LOL! Better yet, he should put LS1 motor and tranny. It gets 30+MPG on highway cruise (b/c of gearing and torque it produced) and produces over 400+HP.. with heads and cam over 450. That what some people do to RX7s..

abecedarian

And then there's the option of installing a mast and sails.

all the mileage, none of the fuel.

kd

yea and then you can get a fan to help the wind out. honestly it sounds like this guy dosent need any advice.

kd

yea and then you can get a fan to help the wind out. honestly it sounds like this guy dosent need any advice.

91Toyota

How about weight reduction? Removing bed, fiberglass hood/fenders, no bumper...just a thought...lol

Kiwipushrod

Hey Guys,

Wankel, and Tesla.....died, Broke.

We're all in the same Boat, energy wise........Do You have a contribution, or an Ego?

Please show Me that "Yotatech", has some thing to offer, other then cupholder mods, and "nice" swordfight's......

Luv Ya, Kiwi

STEvil

Whats not to get about them?

You should look up "turbo lag". They dont stop but when your engine isnt producing enough exhaust pressure to spin them they are only a restriction.

I agree that above a certain amount of boost the fan will cause a very small amount of drag but when the turbo is doing its job the overall intake restriction will be far more of a concern than any correctly operating fan. The fan is not meant to take over the job of the turbo though, it only provides a slightly positive increase to intake air volume due to the restriction of the intake system. It is an alternative to a ram-air or scoop type setup where bugs/rain/mud/water etc may be an issue.

Ah, now I understand why you are reading this all wrong. The fan is NOT inline with the turbo. It is placed before the air filter (or after it, preference and fan performance will determine). The only hot air will be produced by the turbo. The air the fan takes in will be as cool as whatever is going into the mouth of the intake.

BOV's (for exhaust turbos) are for when pressure exceeds or reaches a set point only. At idle a turbo produces no positive pressure. You are thinking of a supercharger.

Cant say I disagree but if you're just gonna buy something and not try to improve it why bother posting on an enthusiast forum other than to wave your wang around?

Skinsfan - Thanks, 2.5" exhaust it will be.. someday

KD - Thanks for the support, class act troll you've been

EDIT

Well said Kiwi

Robert m

iTrader: (2)

like i said before, go out and try all this stuff you think is going to help. then after you have waisted your time and money doing these "mods" come back to the forum that told you it was not going to work and admit your defeat because your not looking for advice your looking for someone to agree with you about your dumb idea.

and dont you think that if putting any type of fan in front of your turbo would in fact do anything positive to your engines efficiency that somewhere one manufacture would be doing it in at least one production vehicle?

Herblenny

I don't know why but I feel that you still don't understand how turbo works. When engine is running, your exhaust is hitting the turbo and your turbos is in spin. When turbo is in spin, is pulling and pushing air.... like a fan.

Again, you are contracting yourself a bit here... Fan outside of air filter is completely useless as air after filter IS TURBO!

If its after the turbo, its same as what I stated before, it would be restriction.


No. That's Pop off Valve. Which is to relieve pressure so excessive pressure can't be reached. BOV is to relieve pressure so that turbos don't come to a sudden stop.... which will eventually damage the turbos. Most BOVs have higher pressure settings than what most runs. If your BOV leaks, then you have boost leak. Which most turbo owners don't want.


No, I'm not saying you shouldn't try.. But when you understand how something works and think about the application, thats when I call it a smart decision. I'm just here to help and pass on some of the knowledge I know. I'm sure you might already know, but there are way too many misinformed info out on these forums. Just trying to correct some of these myths and hype so you don't waste your time. I might not be an expert on 4runners but I do know one or two things about turbos and efi tuning. If you prefer not to hear from me, no problem.

91diesel

I think the idea of turbo 'lag' and that a turbo isn't producing any boost at idle is incorrect. I have a 3.0L turbo diesel with a boost/vacuum gauge. It never shows vacuum..... If the turbo wasn't producing any boost I would show a vacuum at idle instead of zero boost. That tells me that the turbo is boosting enough at idle to zero out the vacuum which can be as much as 25-30psi in some cars. Now if you have a fan that can push more than 30psi into the turbo intake you're on to something, I've just never seen a computer fan do that.

Herblenny

No computer fans I know of will produce 'boost'. Unless the electric motor could spin in excess of 100K RPM.

Also, most pressure/boost you see are measured from intake manifold. I'm not too familiar with 3.0L diesel turbo but most turbo gas powered cars I've seen shows vacuum when TB is closed. The vacuum from the intake manifold is usually used to open BOVs and such. Also remember that turbo boost is usually controlled by the waste gate, which dumps exhaust gas so turbos don't spool as much.

Also, it all pending turbo size and type that makes a difference in lag and amount of air it flows. Its highly unlike that turbo STEvil is using is big enough for additional air flow. If its large, then solution would be to goto smaller turbo for better response/spool or ball bearing turbos.

Junkers88

Although I don't have a turbo I did get 23.9 mpg in town (I'm only on the highway for about 2 miles each day) on my last tank so if the turbo model is even 10% more efficient than the regular 22re then I woldn't be surprised if you can get 25mpg out of it.

I (was) running stock tires and had done a rather large tune up. I even pulled the camper shell off to lose some weight. The way I drive may have something to do with it also. I try to shift before 3000rpms and like to cruise at right around 2000rpms. Sometimes this means I'll be going through town in a 35mph zone in 4th gear.

Of course now that I have 31's on there my mpg is going to change, at least until I "relearn" how to drive it.

Good luck!

Herblenny

There are also some talk of using water injection to increase MPG as with water injection system will help with detonation by lowering intake temp and use more aggressive timing to get maximum HP. I've read about this when I was searching about water injection on my turbo rotary power car. Far as what I've read, it worked for few people.... but again, this goes back to EFI tuning. Just adding water wouldn't do anything.. as now I saw few scams for increasing MPG.