Landtank MAF. (1 Viewer)

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They told me to remove it because it looked like the computer was pulling timing and power. Whether it was dangerous or just excessive because the computer was now in the wrong place in the timing map is unknown. It only seemed to happen above 4000rpms so for the week I left it on I just did not drive over 4000rpms. Like I said I feel I have done every little thing possible to give this the greatest chance of success.
 
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Hi Scott, it sounds like the truck might have been heat soaked and detonation was happening if timing was being pulled at 4000+ rpm. At 4000 rpm the truck is in open loop if I remember correctly with or without the Landtank MAF or stock unit. To be sure, I would have to go looking for the old datalogs. It's been a few years since looking at these logs.

On the second dyno run was the intake air temp noted from the obdII port during the dyno run? What was your short term fuel trim and long term fuel trim during the dyno run? Do you have datalogs from dyno run?

Did the shop have fans running in front of the truck during the run?
 
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Probably because it was deemed dangerous to the engine......

I have had to original one on my truck for the past 5 years and 62,741 miles. No CELS due to the MAF. My truck still has not "blown up".... Still the original head gasket too. I would never go back to the factory unit...
 
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Yep fans were run. This shop is not new to the dyno, they just ran a 1400hp supra through and a 1250hp 5.0 mustang.

I have the scan gauge plugged in all the time water temp, intake air temp, idle, and mpg. The intake air temp was only 75 degrees. It was on a day that was only 55 or 60 outside.

If you have a dyno I would love to see it. My truck had no pings and had more power with the stock MAF housing and sensor so it didnt run out of fueling capacity.

There are two possibilities that I can see. Perhaps it does need longer than 40 min to relearn the new MAF housing and sensor perimeters or perhaps it makes the computer perceive it is in a different place in load/timing map.

If it just takes longer to learn I will find out tomorrow after my next dyno. If the results are the same I will post the dyno's before, during and after for everyone to see, I will show the brand new sensor installed into the MAF housing, the new MAF housing in the truck, the truck on the dyno, and the numbers from the dyno.

I could care less one way or the other. I make $0 off the product, I have already spent the money to obtain it, I paid $145 for the brand new Toyota sensor, not to mention I will have spent $225 on dyno fees just to get the information out there. I am doing this because I like to know what is going on with my motor when I make changes and there is zero data out there. I ask again if anyone has any data that shows the expected gain please can I see it? It would help me if indeed there is an issue with my truck but I very highly doubt there is. If it is pulling timing because it's in the wrong point in the timing map but not because there is pinging you're not going to have detrimental effects to the motor so it makes sense that your motor hasn't blown up, you're just loosing power in the high RPM range. Butt dyno's have proven over and over to not be accurate.


Here are a couple photos of their usual work, it's a very well run shop with great experience. Mud has some great vendors but this is not their wheelhouse.




Hi Scott, it sounds like the truck might have been heat soaked and detonation was happening if timing was being pulled at 4000+ rpm. At 4000 rpm the truck is in open loop if I remember correctly with or without the Landtank MAF or stock unit. To be sure, I would have to go looking for the old datalogs. It's been a few years since looking at these logs.

On the second dyno run was the intake air temp noted from the obdII port during the dyno run? What was your short term fuel trim and long term fuel trim during the dyno run? Do you have datalogs from dyno run?

Did the shop have fans running in front of the truck during the run?

image-356337878.jpg


image-1658144132.jpg
 
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I make no money from the product either. Paid full price like everyone for the original unit. I never bothered with a dyno run. 4wd dynos around here 5 years ago were not common so no dyno. Max air flow I have seen with the LT MAF is around 26 lbs/min. vs around 23 lbs/min on the stock unit.

I saw your thread on the truck. The truck is very clean and has had a lot of work performed. Are you able to datalog the truck during the dyno? I am not up on the Scangauge, can it datalog and dump a .csv file?

Either way best of luck with the dyno run.
 
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Ok well that is one data point, if nothing else changes we should see a 13% increase in HP if you can add 13% more air.

The Scangauge is just a consumer level OBDII reader/display that gives you realtime data. It isn't used for logging that is all done at the dyno. I only referenced the OBDII because I watch it religiously since I have it installed fulltime and I know I was concerned that the lower temp would skew the dyno readings when I did the after on the exhaust system (which did show a 10% gain) since the before was done with almost 90 degree IAT.

But as we all know just adding more air doesn't mean you are adding more power. It is a good data point to know though. Did you see the same MAF voltage when flowing more air?



I make no money from the product either. Paid full price like everyone for the original unit. I never bothered with a dyno run. 4wd dynos around here 5 years ago were not common so no dyno. Max air flow I have seen with the LT MAF is around 26 lbs/min. vs around 23 lbs/min on the stock unit.

I saw your thread on the truck. The truck is very clean and has had a lot of work performed. Are you able to datalog the truck during the dyno? I am not up on the Scangauge, can it datalog and dump a .csv file?

Either way best of luck with the dyno run.
 
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Oh and cattledog, my truck was pulling timing as evidence on the dyno and I had zero check engine lights and no external way of knowing it was happening, not even OBDII codes that didn't trip the CEL. So really the only way of knowing would be on the dyno. I wasn't going to post this if the next dyno did in fact come out better, but even if it still does, this just shows that you should drive easy on your truck after the swap for a while.

So here is my original before and after, and I will have another after tomorrow at 10:30 after having driven the truck for a week with the housing in place to give the computer time to "relearn"

The red is the before, OEM housing and original OEM sensor

The blue is Landtank MAF housing GENII sleeve, with new OEM Toyota sensor.

dyno.jpg
 
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Agreed that just adding more air does not equal more power, timing and accurate fueling are needed too. I would have to find the old logs to give accurate data on the direct ratio of the voltage to calculated air flow. BTW, the truck never felt like a 13% more power was added after swapping housings. The truck did run much smoother after addition of the housing and new sensor. Throttle response was faster too. Idle rpm also quite bouncing from 600 to 650 rpm to an even 590 to 600 rpm. Still runs that way today.

Does the shop datalog from the obdII port while running the dyno? I just would not know having never had a dyno done. These trucks running correctly never had an issue with too little fuel. Most ran stupid rich after hitting open loop even with high miles and poor maintenance.

If the shop does datalog from the obdII port, a .csv file with rpm, MAF voltage, timing, load, air intake temp, lbs/min and ltft and stft would be interesting to see.
 
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I am fine with the posting. CELS only trip when the sensor(s) are out of the normal operation range. For example if the bank two o2 sensor is greater than 20+% the ecu dumps a code.

This is the first dyno I have seen for the housing thanks for spending the money. I have the first gen housing with the FPR blocked. No experience with the second gen. housing. I do understand the the fpr is not blocked on the 2nd gen housing.

How do you know that timing is being pulled from the dyno scan, did I miss something on the graph? On the side, tip in throttle does look better with the housing.
 
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Hmmm that is interesting the set idle by the computer should be 650+- So to have it sit at 590 seems a little low. I wonder if your Idle Air Speed Control Valve is not opening far enough to allow for the 650 idle. Or if maybe the additional size of the MAF allows for slower air speeds at idle to get the same volume of air? But yeah I just double checked the emissions sticker under the hood and idle is supposed to be 650rpms.



Agreed that just adding more air does not equal more power, timing and accurate fueling are needed too. I would have to find the old logs to give accurate data on the direct ratio of the voltage to calculated air flow. BTW, the truck never felt like a 13% more power was added after swapping housings. The truck did run much smoother after addition of the housing and new sensor. Throttle response was faster too. Idle rpm also quite bouncing from 600 to 650 rpm to an even 590 to 600 rpm. Still runs that way today.

Does the shop datalog from the obdII port while running the dyno? I just would not know having never had a dyno done. These trucks running correctly never had an issue with too little fuel. Most ran stupid rich after hitting open loop even with high miles and poor maintenance.

If the shop does datalog from the obdII port, a .csv file with rpm, MAF voltage, timing, load, air intake temp, lbs/min and ltft and stft would be interesting to see.
 
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Interesting. That dyno chart is showing 30 to 40 more hp off the line. That explains what seems to be a unanimous observation that throttle response is much better with increased pull off the line.

I ran headers for a long time before I put the LT MAF on my truck and I also ran headers for a couple years with the LT MAF. I always felt that gains were felt throughout the power band. More air could mean more power but an NA motor has limits to how much more air it can suck in. Extractors or headers are able to increase the amount of air by suction or scavenging and less intake restriction will increase that effect. Though I never dyno'd I did on several occasions provoke various stock cruisers to help me test my mods via racing. I always pulled away from the stock trucks easily and that was on 35" tires. I can't say it was only the header exhaust or the MAF, but I can say that those were the only differences in every case other than possible weight differences.

I am wondering if the motor needs to spend some time in those upper rpm ranges in order for the ECU to learn the new MAF.
 
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The point at 57.5ish mph where the graphs falls off sharply was the computer pulling degrees of timing. On the next graph I will have them plot it in RPM's and add the AFR data, but the truck is not lean and it was not pinging, the shop simply believes it is in the wrong point on the perceived load/timing map and this is the result.

I am not sure if you are talking specifically about the 80 series but I have seen codes on OBDII readers that didn't trip the CEL some people call them pending codes, but it does happen. I have seen it with misfires.


I am fine with the posting. CELS only trip when the sensor(s) are out of the normal operation range. For example if the bank two o2 sensor is greater than 20+% the ecu dumps a code.

This is the first dyno I have seen for the housing thanks for spending the money. I have the first gen housing with the FPR blocked. No experience with the second gen. housing. I do understand the the fpr is not blocked on the 2nd gen housing.

How do you know that timing is being pulled from the dyno scan, did I miss something on the graph? On the side, tip in throttle does look better with the housing.
 
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Factory manual is 650 +- 50 rpm. Could care less about the 590 being 10 rpm too low. The truck is running fine for the past 62000+ miles. Look forward to your dyno charts in the am.
 
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The point at 57.5ish mph where the graphs falls off sharply was the computer pulling degrees of timing. On the next graph I will have them plot it in RPM's and add the AFR data, but the truck is not lean and it was not pinging, the shop simply believes it is in the wrong point on the perceived load/timing map and this is the result.

I am not sure if you are talking specifically about the 80 series but I have seen codes on OBDII readers that didn't trip the CEL some people call them pending codes, but it does happen. I have seen it with misfires.

My bet is that the truck is at about 3750 rpm in open loop and dumping fuel like mad, not pulling timing unless you have acutal number data. MPH is useless, rpm are the correct value to plot as you pointed out. Have them check the stoch. at the tailpipe. My bet is that you are around 10.4:1 or lower. This is just the limits of the 1996 ECU in open loop.

I am not aware of any pending code memory/ cycle count for the 1996 lx450 ecu. But there could be.
 
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I am wondering if the motor needs to spend some time in those upper rpm ranges in order for the ECU to learn the new MAF.


That is learning is the the LTFT adjusting to the new housing and sensor in closed loop. LTFT is used to calc the fuel in open loop. That is what I recall from about 5 years ago.
 
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Verdict is in. I have a MAF housing and new toyota sensor for sale for $200. Haha

So after a week of driving the car, nothing got better and in fact it's worse. I am definitely pulling it off and going back to stock.

Blue is the baseline with stock MAF
Red is last weeks right after the swap
Green is today.

AFR was 10:1, definitely not lean and no pinging

image-2344575031.jpg
 
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Scott...Thanks for going through all of the effort. Good to have real hard indisputable numbers
 
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