The Mk3 uses the Karman Vortex system - essentially all smoke and mirrors ...well maybe not the smoke.
93-94 truck VAF to MAF conversion project
- Thread starter semlin
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I had time to think about this and the non turbo supras had the Vane style while the turbo units had the Karman Vortex style. It was the Turbo'd Supras that got the AFM from the Lexus which automatically tuned them for larger injectors. So it was a win win situation, better breathing and more fuel.
I honestly don't think it's wise to plug a Vortex AFM into our trucks.
I honestly don't think it's wise to plug a Vortex AFM into our trucks.
Ah good point - honestly I never looked into the non turbo.
semlin
curmudgeon
- Thread starter
- #145
that would explain some of my confusion.
here is a thread for a normally aspirated mark 3 conversion to an LS-1 maf using that MAF-T product we have discussed before in the other thread.
writeup: MAFT Pro install for 7M-GE - SupraMania
what interests me is this item in the summary.
"9) V-Out1 Mode - (17) Toyota VAF"
It thus looks like the MAFT might have the ability to convert a MAF signal to VAF output built in (maybe mapped for a mk3 ??). If so, i know the maf-t is a newer product than split sec and more adaptable with more functions for about the same money. otoh I posted on the maf-t forum last year asking if they supported this and got no answer from their tech guys.
I would love the guy on Yota tech to ditch the GM maf and get an air cleaner from a 2003 4cyl Camry and tune that sensor. That sensor housing setup should make dialing in his 22RE a lot easier as it's tuned for a 2.2 litre engine already and would lay the ground work for our trucks nicely. Toyota designs there AFMs to respond similarly from application to application they just change the sample size according to the engine's displacement.
Originally Posted by converter guy
I was wondering how well the ECU would respond to a more accurate metering system as well. I'm sure that a large part of the improved responsiveness I've seen with both the GM MAF and SD is due to the ECU not only getting far more accurate air flow information but also due to the fact that the signals aren't as erroneously dynamic as the signal you get from a potentiometer. The ECU responds to all my entered corrections.
TurboCruiser saw the same thing with my MAF. While reading through the OBDII port he saw more frequent updates from the MAF sensor. The new ones just run cleaner and more accurately.
I was wondering how well the ECU would respond to a more accurate metering system as well. I'm sure that a large part of the improved responsiveness I've seen with both the GM MAF and SD is due to the ECU not only getting far more accurate air flow information but also due to the fact that the signals aren't as erroneously dynamic as the signal you get from a potentiometer. The ECU responds to all my entered corrections.
TurboCruiser saw the same thing with my MAF. While reading through the OBDII port he saw more frequent updates from the MAF sensor. The new ones just run cleaner and more accurately.
If you are just going to invert the output i.e. 0-5V transformed to 5-0V you should be able to get away with a simple op amp circuit. (Sorry the Supra AFM sidetracked me - I meant to say this in the original post)
The circuit is simple but you may need to buffer it depending on the current you need to draw.
Look here: Operational amplifier applications - Wikipedia, the free encyclopedia
The circuit is simple but you may need to buffer it depending on the current you need to draw.
Look here: Operational amplifier applications - Wikipedia, the free encyclopedia
semlin
curmudgeon
- Thread starter
- #150
i spoke to split second. they feel the inverted output on their system will be close enough to just plug it in and start tuning although if i wanted I could plug in the max and minimum voltage outputs on the VAF (which we have above) and try to roughly scale it beforehand. they recommend tuning it with a wideband sensor and meter instead of wasting time by first trying to datalog the vaf signal and approximate it on the maf.
and their psc1-005 can include a datalogger option for another $50 which i would probably have to use since I would be doing this solo. So $423 plus I would need a wideband sensor and meter.
so i may call maf-t tomorrow and ask them whether there's can do it. according to this link
Q & A: MAFT Pro + 7M-GE - POST ALL QUESTIONS, COMMENTS AND PROBLEMS HERE! - SupraMania
their $269 model can now do the vaf inversion for a supra mk3 normally aspirated and can also take in a wideband signal. this sounds like a better deal than splitsec if it works.
I am also not ruling out the diy or yotatech approach but the problem is i need a wideband sensor and meter anyway, so the maf-t may be as good a deal plus tuneable
and their psc1-005 can include a datalogger option for another $50 which i would probably have to use since I would be doing this solo. So $423 plus I would need a wideband sensor and meter.
so i may call maf-t tomorrow and ask them whether there's can do it. according to this link
Q & A: MAFT Pro + 7M-GE - POST ALL QUESTIONS, COMMENTS AND PROBLEMS HERE! - SupraMania
their $269 model can now do the vaf inversion for a supra mk3 normally aspirated and can also take in a wideband signal. this sounds like a better deal than splitsec if it works.
I am also not ruling out the diy or yotatech approach but the problem is i need a wideband sensor and meter anyway, so the maf-t may be as good a deal plus tuneable
Are the injectors on the 93+94 trucks the same as the 95+ trucks?
it has to do with getting the bore of the MAF correct to start with. If that is done correctly I think that a straight conversion to start with will be close and then you can tweak it in. If you get that wrong you will be running rich or lean and then the whole curve will have to be built which will be a big job to get it right.
semlin
curmudgeon
- Thread starter
- #154
i forgot we have an online epc resource. the injectors are the same part and the whole assembly appears identical.
http://www.toyodiy.com/parts/p_U_1997_TOYOTA_LAND+CRUISER_FZJ80L-GNPEKA_2211.html
http://www.toyodiy.com/parts/g_U_1993_TOYOTA_LAND+CRUISER_FZJ80L-GNPEKA_1.html
http://www.toyodiy.com/parts/p_U_1997_TOYOTA_LAND+CRUISER_FZJ80L-GNPEKA_2211.html
http://www.toyodiy.com/parts/g_U_1993_TOYOTA_LAND+CRUISER_FZJ80L-GNPEKA_1.html
Did you guys ever use the modern MAF meter on the older Cruisers. I am very interested because on my side of the pond there are very few VAF (pre '95)in fact I am beginning to think that mine is the only one!!! The Gas powered Cruiser was only available from late '95 onwards so there are plenty of the later type available. It would be interesting to know the results.
this came up in conversation while out in Moab. My buddy has a 91 and was thinking about getting this split second unit for us to tinker with.
PSC1-004 Programmable Signal Calibrator
PSC1-004 Programmable Signal Calibrator
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Wow. Is this too good to be true????
semlin
curmudgeon
- Thread starter
- #159
whoops, sorry accidentally answered your post by editing it...
the 005 model looks to be perfect for our application. nice find. i am pretty sure when we looked at the wiring before we can use the air temp sensor signal from the new maf unit so it would not require the extra temp sensor.
do our VAFs have a fuel pump switch...
