[Brian894X4]

OK, first of all, none of what I'm about to report is conclusive. This is just observation from reading the scangauge and other factors could be at play here and I'm not 100% sure how accurate the scangauge is in the following readings.

But basically I ordered Landtank's MAF housing last week and just got it today. Awesome product! Fast shipping! I purchased a used sensor out of a 2003 Camry for about $40. Considering the numbers I produced tonight with my first runs, I really, really wish I would have made some recent runs with the old MAF.

Among other things, I tested the set up using the scangauges h.p. meter. I don't know how the scangauge determines h.p. but I assume after being imputed several factors like engine displacement, it uses it's numerous sensor readings to come up with a brake h.p. reading. Rather than compare the scangauge numbers to other data, its probably most useful to compare scangage to scangage on the vehicle in the same conditions. I couldn't really replicate conditions. My original readings were at 70 degree intake temp. The new readings with the Landtank MAP was at 40 degrees intake temp.

In going over my notes, when I made a number of h.p. test runs last year, the highest numbers I could achieve on the scangauge was 246 (brake) h.p. I was typically maxing out in the upper 230s. This is with a bone stock engine, and original MAF.

Tonight, after the MAF install, the highest reading I got was 306. Most runs showed in the very high 290s.
The only difference in the engine itself was the Landtank MAF.

Air temp was at least 30 degrees cooler, so we can probably attribute around 6% of that gain to the colder denser air. That leaves us with about a 15+% power gain that can't be accounted for, except for the Landtank MAF.

Seat of pants experience did seem to confirm a significant power increase at WOT and upper rpms. When pushing past legal speeds, even going uphill and loaded down to over 6500lbs, it just wanted to keep speeding up. Not what I remembered with the old set up.

But the numbers I was seeing almost seemed too significant, even taking the weather differences into consideration. I can't believe that an MAF would make that much difference. I really wish I had taking direct readings using the old MAF on the same night for a more direct comparision. I'm almost intriqued enough to put the old MAF back and run the numbers, then run home and put the new one on and do a direct face off.

So, has anyone else with a scangage experienced similiar results? Gains of more than 15%?

On a slightly seperate note, the 1FZ was produced long after 1997 and as it turns out later model 1FZs made more power. 221 h.p. and 285ft/lbs of torque to be exact. And this is not the VVTi models that made 240 h.p. These are just the run of the mill Aussie 78 series models. I know Toyota improved the intake system and made a few other tweeks, but I've been wondering if Toyota added the same type of sensor or something similiar in later 1FZs that really helped out this motor and now those of us with the Landtank MAF appear to be experiencing the same type of gains.

Anyway, more later......

[fjfar80]

Are you running a super charger or just normally aspirated?

- Mark

[Lugboot]

He said, "bone stock engine":

"This is with a bone stock engine, and original MAF.

Tonight, after the MAF install, the highest reading I got was 306. Most runs showed in the very high 290s.
The only difference in the engine itself was the Landtank MAF"

[The Lovely Boyo]

So if I put two of these in series I get 30%? Not worth bothering with my turbo mod lol

Only joking, ahem.

Brian, you've had the truck long enough to know so this sounds intriguing. Have you put high octane in by mistake? The scangauge hasn't been altered so these figures can be relied on.

I think for your own sanity (and ours) you have to do that back to back test! (Go on, its only a couple of hose clamps).



Now where's Landtanks contact details? I gotta get me one......

[Riad]

I have been pretty happy with it. It's been a while since I installed it. After 2.5" exhaust, I have been noticing more power increase. The power is noticeable at both ends; 0 - 60 mph and 40 - 75 mph or higher. I might put my sway-bars back on one of these days.

[fjfar80]

Lugboot...I realize exactly what he said...just knowing all the modifications he has performed...I wanted to double check to ensure that he was normally aspirated. I have heard many folks say...bone stock...and then you find out they had this or that...and a little of that. Just wanted to double check.

Cheers.

- Mark

[bpassmore]

Originally Posted by Lugboot

He said, "bone stock engine":

"This is with a bone stock engine, and original MAF.

Tonight, after the MAF install, the highest reading I got was 306. Most runs showed in the very high 290s.
The only difference in the engine itself was the Landtank MAF"

this was kinda smartass....

[sleeoffroad]

The scangauge can only calculate HP. Without knowing what it is that it uses, it is impossible to interpret the results. Your initial reading is way high for wheel HP. Here is a chart showing wheel HP for a 97 truck in stock form (ignore the turbo). So as you can see it is way lower.



You might be reading a difference, but in real world terms in would be way smaller. I think the tool is good to see what changes you made if you monitor fuel trims etc etc.

Did your IAT drop 30 degrees just by swapping in the new MAF? Or was this a different day.

[e9999]

Christo beat me to it (as usual ), but yes, these HP numbers are way overoptimistic. No way the SG can calculate HP accurately, but even with that in mind, the numbers are crazy wrong. It's saying you got more HP (brake?) stock and old than the truck was ever spec'ed as having HP at the engine when new...

Anyway, sure, having colder air could result in an increase in HP since you can then cram more fuel in there. Then again, more power yes, but also more gas...


Having said that, this is interesting, and I'd like to see some more numbers on it all.

[Brian894X4]

I know this sounds crazy, so like I said in the original post, the scangauge's horsepower calcuations are not comparable to the factory SAE h.p. readings, so I wasn't implying one single bit that the truck makes 306 h.p. as we normally think of 306 h.p. The scangauge is apparently caculating something close to or more than real world gross h.p. which is much higher than the factory h.p. readings and FAR higher than dyno reading at the wheels. This is why I'm only comparing the original scangage reading before the MAF mod to the new scangauge reading after the MAF mod on a percentage basis. I'm also not saying that other factors couldn't be at play here, including the scangauge itself being inaccurate.

The engine is absolutely bone stock, no mods, no supercharger, original exhaust system, intake system, factory filter, etc, etc. Currently has about 106,000 miles on it.

There was a signficant difference between air temperatures of the original reading and this new reading. My notes from the original readings taken last year indicated 70 degrees F, which is intake temp. I didn't record outside temp at the time. Intake temp for the new reading was about 40 degrees F with an outside temp of about 30 degrees F. So, using the formula of 10 degree drop = 1.8% gain and rounding off, I've wiped out 6% of the difference and attributed that to intake temp.

By the way, I'm not implying that the new MAF has any affect on intake temp, this is purely due to outside ambient temp differences.

OK, so I found some additional scangauge notes that I took of other readings. I found that after another test last winter, intake temps were about 50 degrees, I was able to achieve a max scangauge h.p. reading of 255 on the Land Cruiser. (stock MAF) I was taking these readings because I had rented a 2008 4Runner with the 4.0 V-6 in which I also took some scangauge readings and achieved a maximum h.p. rating in the 4runner of 279 scangauge h.p. with the 4Runner's 4.0 engine. Because there was an 11% difference in factory h.p. ratings between the two engines and there was a 10% difference my own readings, I drew the conclusion that the scangauge was at least relatively accurately reading the difference in h.p. between the two rigs.

So, with the new data, comparing 255 scangauge h.p. on my rig last winter (at 50 degrees intake) with 306 scangauge h.p. (at 40 degrees intake) last night with the new MAF, what is going on here? We're talking about a 20% total difference in max brake h.p. Does it feel like a 20% difference? That's hard to say, because I had to go off of memory of how my rig behaved before rather than being able to compare on the same day. The engine definately felt like the upper end had been opened up and that it could rev faster and wanted to pull harder and higher rpms. My rig is 6500lbs and it felt like it really wanted to go a lot faster, including up a hill than I ever remember it being capable of, especially at this weight.

Now, the felt power increase was NOT across the powerband as far as I could tell. There didn't seem to be a significant increase at the lower end. Maybe slightly better throttle response, but the felt gains to me were all at the upper end.

I really wish I could see if anyone else has had the same results or has dyno'd the thing for some hard numbers to confirm my own results or see if there's something else at play here.

Trust me, I know this sounds crazy as hell. At this point I'm gonna have to swap back in the old sensor and do some test runs on the same night under the same conditions to see what's going on here. I'll probably do that later this week and post the results.

[e9999]

one question would be about How the SG calculates HP. I don't know. But I assume it has to do with using gas consumption figures, maybe throw in some rpm factor, perhaps average efficiency figures and the like. Could be a lot of things. (I don't think these devices are anything like the miracle magic gizmos that some wish / think they are.)
Any chance you could have changed some settings?

Anyway, if you're saying that you got something like maybe 10% more HP cuz the intake air temp was 10F lower, that seems a bit much... Wouldn't everybody in Minnesota beat drag race records with their Pintos if that were true?

[Lugboot]

Originally Posted by fjfar80

Lugboot...I realize exactly what he said...just knowing all the modifications he has performed...I wanted to double check to ensure that he was normally aspirated. I have heard many folks say...bone stock...and then you find out they had this or that...and a little of that. Just wanted to double check.

Cheers.

- Mark

I was trying to help out and didn't have time to insert smilies and whatnot--sorry if you took it the wrong way.

Originally Posted by bpassmore

this was kinda smartass....

See what not using smilies gets you? I was simply trying to point out the part where the OP addressed the engine config and I didn't have time to make it feel-good, apparently. Was not intended to come across as smartass. Sometimes people miss things in longer posts. it's happened on here before.

: clap:

Okay, now the above string of smilies was smartass, I admit.

On a technical note, I need to move this farther up my list of mods.

[bpassmore]

[sleeoffroad]

Originally Posted by Brian894X4

I know this sounds crazy, so like I said in the original post, the scangauge's horsepower calcuations are not comparable to the factory SAE h.p. readings, so I wasn't implying one single bit that the truck makes 306 h.p. as we normally think of 306 h.p. The scangauge is apparently caculating something close to or more than real world gross h.p. which is much higher than the factory h.p. readings and FAR higher than dyno reading at the wheels. This is why I'm only comparing the original scangage reading before the MAF mod to the new scangauge reading after the MAF mod on a percentage basis. I'm also not saying that other factors couldn't be at play here, including the scangauge itself being inaccurate.

Yes, but playing with percentage is dangerous. If the scangauge is already that far off, then the increase is also way off. I just wanted to post some real data on HP.

There was a signficant difference between air temperatures of the original reading and this new reading. My notes from the original readings taken last year indicated 70 degrees F, which is intake temp. I didn't record outside temp at the time. Intake temp for the new reading was about 40 degrees F with an outside temp of about 30 degrees F. So, using the formula of 10 degree drop = 1.8% gain and rounding off, I've wiped out 6% of the difference and attributed that to intake temp.

By the way, I'm not implying that the new MAF has any affect on intake temp, this is purely due to outside ambient temp differences.

Ok, the way it read was that the MAF made the change, which I did not expect it to do, just wanted clarification on that.

We're talking about a 20% total difference in max brake h.p. Does it feel like a 20% difference?

20% estimate is still huge for a simple mod like that.

[Brian894X4]

As far as the percentage in change the total percentage in change from the highest h.p. reading that was ever able to get out of the 1FZ prior the MAF mod to what it was last night after the MAF install was about 20%.

Assuming for the sake of argument that the number is accurate, how much of that was attributed to the MAF and how was attributed to different temps, or any other factors, I don't know. I've read the formula about cold air having the 1 to 1.8 % difference for every 10 degrees. Don't know if that's accurate or not, but I could see the temp having some affect, since last night was colder than on any of my previous runs prior to the MAF mod. But I don't think it would be more than about 5-6% based on the above formula.

The scangauge requires that you imput the displacement of the motor and a few other things. I'm sure it uses the rest of the sensors and based off some formula comes up with it's figure. Some of things that the scangauge can display are gallons per hour usage, ignition timing, intake temp, vehicle speed, rpm, etc.

I think comparing even scangauge numbers between vehicles is probably questionable, because you do have to imput some settings and the sensors between different vehicles are going to be different, but comparing the same exact vehicle and engine between mods, might be useful, I don't know.

If was reading this I'd be questioning it very hard too. As far as what the new MAF does, you'll have to ask Landtank that question or read the many different threads. One thing for sure, the sensor does open up the intake significantly and appears to cause far less airflow restriction. If I read correctly, the new sensor seems to be more accurate as well. Toyota used the same sensor for a wide variety of vehicles once it was developed after the 80 series production ended.

Definately need to do some more testing and comparing to the old MAF, before I can draw any concrete conclusions and see if it was just anomaly.

My gut feeling is that the MAF does significantly improve WOT, high rpm performance at the upper end of the powerband, but how much is in question. I don't honestly think it's 20%, but I think it's something very noticable.

[landtank]

Yeah baby

Programs like this typically will use the speedometer and an input of what vehicle you are driving to calculate HP. It considers the mass of the vehicle and that vehicle must be in stock form. So there is plenty of issues with accuracy.

But it's like a dyno in some sense. Different dynos give different results and will vary on different days.

The best you can do is try and get a direct percentage increase from running both MAFs on the same day, on the same road and then apply that percentage to the factory specs for the truck.

Toyota says the engine make 212hp so the rear wheel horse power would be considerably less.

Another thing that would skew the results is that you are replacing a very old part with a much newer one and some of that increase might also be seen if you used a new stock sensor.

Hey, I love the numbers but I'm a realist also.

[aclos3]

I recently installed the Landtank MAF and read the entire development thread. It seemed like during testing, the best estimate they could get based on air pressure was about an 18hp increase for a stock truck. People with forced induction noticed upwards of 50hp. The gain comes from 2 things: a larger, freer flowing MAF housing that allows more air to get to the engine and a much improved data stream from the sensor. The sensor is more sophisticated so it provides many more data points per second and the freer flowing design of both sensor and housing should allow that airflow to remain laminar and therefore not "wash out." More air + much more useful data to the computer allows the truck to run more efficiently, improve throttle response, and increase horsepower in the middle / upper rpm range. My butt dyno may not be that great, but I'd say the mod makes it feel like it gained just about 20 horsepower. I can also echo the sentiment of other Landtank MAFers in saying that it "feels like 500 lbs came off the truck" -- maybe more!

This mod is fantastic. It eliminated my slight warm idle stumble, and definitely improved throttle response and horsepower. I cannot yet comment on the gas mileage since I installed my MAF yesterday, but people claiming the extra power also seem to notice about 1mpg better in the city. They are certainly correct about the power, so I can only assume their statements about gas mileage are true as well.

[sleeoffroad]

Originally Posted by aclos3

The gain comes from 2 things: a larger, freer flowing MAF housing that allows more air to get to the engine

Correct,

and a much improved data stream from the sensor. The sensor is more sophisticated so it provides many more data points per second

The sensor is analog and sends out a voltage. The ECU is the one that makes that into a number. What you mentioned above is simply not correct. Here is some info on how the system works.
http://www.autoshop101.com/forms/h34.pdf

The sensor might be more sensitive to air flow changes, but the analog to digital is still done by the ECU.

Just to be clear, I am not knocking this mod, just don't like it when info is posted that is not correct.

[TrickyT]

Originally Posted by aclos3

... The sensor is more sophisticated so it provides many more data points per second...

I disagree about the more data points per second. That's a function of the ECU, not the sensor. What is superior about the new style sensor is that it has more dynamic range and, I believe, is more linear at the low and high ends of its dynamic range.

[landtank]

To shrink the sensor in size you need to reduce the sample size needed to get a valid reading. Which means it has to be more sensitive. These sensors are 11 years newer than the original ones. MAF sensor design improvements has been one way that Toyota has gotten a little more HP and fuel economy out of their engines.

While aclos3 might not be technically accurate with his wording I think the basic idea from a layman's point of view is reasonably close.

[sleeoffroad]

Originally Posted by TrickyT

What is superior about the new style sensor is that it has more dynamic range and, I believe, is more linear at the low and high ends of its dynamic range.

Does anyone have data about this? Dynamic range as well as lower end response?

[Brian894X4]

A few points…

Someone mentioned in this thread and in the below comment that h.p. gain could be in the 20 h.p. range. This is about what it felt like to me. See below…

From this thread, post no. 111
http://forum.ih8mud.com/80-series-te...gen-1-a-4.html

Right now I think the testing phase is pretty much wrapped up. We did a comparison between my truck with the stock MAF and Cattledog's with the modded MAF and his truck reported 2 more lbs of air flow. A basic rule of thumb is that for every pound of air you get 10 HP. So a stock truck with my MAf will get basically a 20 HP gain. There is also a torque gain but I'm not aware of any way to quesstimate that from air flow.

My original sensor only had 106K miles on it. The “new” sensor is a used one from a 2003 Camry, unknown mileage, so not new. But I did clean it prior to installing.

Also as far as the accuracy of the scangauge, the h.p. readings at idle on both sensors, which I did record on the same day and under the same circumstances were nearly the same. About 6-7 h.p. at 600-650 rpm. When I test both sensors again, I’ll post all the data I can to verify this.

What I did find out was that gas consumption at idle (in park, no load) went down, even at the same rpm. It measured roughly .45-.46 with the old sensor and now measures roughly .38-.40. I’ve never seen idle gas consumption less than .45 before. I don’t know that this translates to better economy at higher rpms, but rather is probably a function of the MAF actually allowing controlling the fuel mixture better at idle whereas the old sensor used wasn’t really used to control mixture at idle, if I understand correctly.

[Brian894X4]

Another point is that Toyota gained significant power from the 1FZ after U.S. model production ended in 1997. The Aussie 1FZ was later rated at 221 h.p. and 285 ft/lbs of torque. From an Aussie Toyota press release they note the following about the “upgraded 1fZ engine…note the part about the revised MAF sensor....

source...
http://www.pressroom.com.au/pressroo...kits/78kit.htm

------------------------------

Toyota's new LandCruiser 78 Series has the most powerful engine in the 4x4 workhorse class.

It has the improved 4.5 litre EFI-equipped Toyota 1FZ-FE engine, which debuted in LandCruiser 100 Series.

The improved petrol engine has more power and, by a significant margin, the most torque of any workhorse 4x4 engine.

It has 7kW more power and 14Nm more torque than the superseded LandCruiser 75 Series petrol six, without sacrificing fuel economy.

The 4477cc engine delivers 165kW of power at 4600rpm and 387Nm of torque at 3600rpm.

It has more torque than the superseded powerplant from 2800rpm to beyond 4000, with 312Nm available at just 800rpm.

The new engine improves 0-100km/h performance by up to 11 percent (TroopCarrier model).

Toyota's 1FZ-FE engine was redesigned throughout for the introduction of LandCruiser 100 Series.

These benefits have flowed on to the workhorse models.

Power and torque were improved by adopting longer intake runners, new short-skirt pistons with higher piston rings to reduce dead air volume, an all-stainless steel exhaust system with fabricated headers and new engine electronics.

A revised cylinder head provides enlarged inlet ports and a revised combustion chamber design with increased squish area and larger valve seats.

Fuel system improvements include the adoption of full sequential injection with four-hole injectors and a hot-wire type air-flow meter for greater mixture accuracy.

The improved engine adopts direct ignition with three igniters and multiplex diagnostics.

Direct ignition improves reliability and emissions, and reduces service time.

NVH countermeasures include a redesigned cylinder block, with additional strengthening ribs, and reduced reciprocating mass achieved by adopting lightweight pistons.

Emission levels have been reduced compared with the superseded LandCruiser 75 Series petrol engine.

--------------------

That's a lot of improvements to make a gain of what amounts to about 9 h.p. Personally, I wonder if Toyota underrated the new 1FZ. In some very late model 1FZ where they incorporated a VVTi head, they rate the power output at over 240 h.p. It's well known that actual published h.p. numbers are not necessarily dead accurate but more political. In many european countries, the insurance rates are based on the h.p. rating of a vehicle, so it's hard to say. I still suspect that that MAF mod alone is worth at least and probably more than 10 h.p. on our engines, based on my experience.

[landtank]

Originally Posted by Brian894X4

What I did find out was that gas consumption at idle (in park, no load) went down, even at the same rpm. It measured roughly .45-.46 with the old sensor and now measures roughly .38-.40. I’ve never seen idle gas consumption less than .45 before. I don’t know that this translates to better economy at higher rpms, but rather is probably a function of the MAF actually allowing controlling the fuel mixture better at idle whereas the old sensor used wasn’t really used to control mixture at idle, if I understand correctly.

theoretically the fuel consumption at idle should be the same. That is because the ECU is in closed loop and adjusting fuel trim based on O2 readings.

The reason that you are seeing a drop in fuel consumption is that the new MAF reads the idle air flow more accurately and is operating the injectors at a lower duty cycle than with the stock MAF.

This is the reason for removing the vacuum line from the FPR. By removing the vacuum line the fuel rail pressure is now higher at idle and offsets the lower injector cycle that is calculated from the new MAF sensor.

[sleeoffroad]

Rick, the reason there is a vacuum line on the fuel pressure regulator is that Toyota wants the pressure differential between the intake manifold pressure and the fuel rail pressure to stay constant. At idle there is vacuum in the intake manifold, thus you need to decrease the fuel pressure, to keep the pressure differential the same. Disconnecting the line is causing excessive fuel pressure at idle. They did not install the pressure regulator because their sensor reads the air flow incorrectly idle. That is documented in the Toyota tech manuals.

if your MAF is causing high long term fuel trim at idle with the pressure regulator connected to vacuum, then it is measuring the air incorrectly and the truck is trying to adapt to that. You are telling the truck there is less air that what there is and the truck is trying to make up when it sees a lean condition. By disconnecting the fuel pressure regulator you are increasing the fuel rail pressure and it causes more fuel to be injected for a given duty cycle, so therefore the long term fuel trim goes down.

Where is the evidence that your sensor reads the low air flow better?

Also, how are you compensating for the increase in pressure in the manifold on boosted trucks if the fuel pressure regulator is not connected. If you don't leave the pressure regulator connected, the extra pressure in the manifold (due to the boost) is not compensated for and the pressure differential will not be constant again. If you leave the regulator connected, the possitive pressure on it will raise the fuel pressure in the rail, thus overcoming the extra pressure in the manifold.

[sleeoffroad]

On another note, what is your long term fuel trim in closed loop under most driving conditions? Have you ever had a truck measure on a gas analyzer to make sure it is not running lean by checking the NOX readings? You can still be running lean, without tripping codes or having check engine lights.

[Brian894X4]

Rick or Christo,

What would be the consequences of leaving the pressure regulater hooked up with the new MAF installed?

[landtank]

Originally Posted by Brian894X4

Rick or Christo,

What would be the consequences of leaving the pressure regulater hooked up with the new MAF installed?

you'll have an idle LTFT% that is way out of the norm during idle and could possibly throw a code. If you were to do a reset on the ECU, like removing the battery for a long enough period of time, you would be running very lean until the truck got hot enough to enter closed loop and start adjusting for that condition.

In my testing the only time that the vacuum line influenced the FT% was during idle and it accounted for a shift of about 18% from what I remember.

[Brian894X4]

By the way, I was thumbing through the International EPC over the 70 series board (awesome resource!) and it doesn't appear that any of the 1998 and later 1FZ-FE engines used any kind of MAF sensor. They all had an intake temp sensor, but that's it. I was trying to see if maybe they used the same part we retrofitted.

So, I'm curious how later model 1FZs controlled fuel mixture. In other searches, I've read that at least some models also didn't use O2 sensors?

The other interesting thing I found is that it looks like the 1998 and later 1FZ engines used the exact same fuel pressure regulator, same part and everything. However, I can't make heads or tails if the same vacuum line is used or not.

Here's the 1992-1997 diagram. 1FZ engine
http://www.toyodiy.com/parts/p_U_199...PEKA_2211.html

Here's the 1998-2008 diagram. 1FZ engine
http://www.toyodiy.com/parts/p_G_200...PNKQ_2211.html

[TrickyT]

Originally Posted by Brian894X4

By the way, I was thumbing through the International EPC over the 70 series board (awesome resource!) and it doesn't appear that any of the 1998 and later 1FZ-FE engines used any kind of MAF sensor. They all had an intake temp sensor, but that's it. I was trying to see if maybe they used the same part we retrofitted...

But in an earlier post you quoted one of the benefits of the upgraded 1FZ-FE engine as...

"Fuel system improvements include the adoption of full sequential injection with four-hole injectors and a hot-wire type air-flow meter for greater mixture accuracy."

The hot-wire air-flow meter they are referring to is a MAF sensor. See this Mass flow sensor - Wikipedia, the free encyclopedia link for a description of how a hot-wire MAF works.