Ok the MAF topic again - limits.
Adkoonerstrator
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Re: Ok the MAF topic again - limits.
XLR8NSS got me a little confused, when he said "it would be nice to run in closed loop". I thought thats the way our PCM worked.
:p 
At WOT our stock computer is in OPEN loop mode. It does not use feedback from the O2 sensors in OPEN loop. While cruising it is in closed loop mode and uses the O2 sensors to help keep a ~14.7:1 A/F ratio.
The FAST system uses wideband O2 sensors and runs in closed loop at all times from what I understand. I really don't know a whole lot about it.
John
Re: Ok the MAF topic again - limits. ChrisB, thanks for the info. It's nice to see that they are at least recognizing the LS1 market. I called them about a year and a half ago and they told me to they weren't doing any custom stuff for the LS1.
-Geoff
-Geoff
Thread Starter
TECH Senior Member
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From: Columbus, ohio
Re: Ok the MAF topic again - limits. just emailed Prom and got this reply on how to get a higher MAF meter.
Hi, I have a turbocharged LS1, and am trying to get past the limited 62lb/min GM MAF meter.
I see you have a conversion box to equip the GM cars with pro-m ford MAF meters. What all is involved in doing the swap, or which components are needed, and their cost. WHat is the mhz limits of these componets.
A few others along with myself are interested in increasing the capablities of the ls1 MAF for FI applications.
thanks.
We make two boxes, standalone, one is a calibrator that allows you to adjust the meter that is on the car, we also sell a converter that allows the Ford MAF to work on a GM vehicle. Cost of the calibrator is $445. Cost of the Converter is $390. We also have an new MAF tuner which lists for $299 which is lap top or desk top programmable. The unit allows you to tune 31 points on your maf transfer function
Jim Gonzales [sales@pro-flow.com]
so that would = $1134
Hi, I have a turbocharged LS1, and am trying to get past the limited 62lb/min GM MAF meter.
I see you have a conversion box to equip the GM cars with pro-m ford MAF meters. What all is involved in doing the swap, or which components are needed, and their cost. WHat is the mhz limits of these componets.
A few others along with myself are interested in increasing the capablities of the ls1 MAF for FI applications.
thanks.
We make two boxes, standalone, one is a calibrator that allows you to adjust the meter that is on the car, we also sell a converter that allows the Ford MAF to work on a GM vehicle. Cost of the calibrator is $445. Cost of the Converter is $390. We also have an new MAF tuner which lists for $299 which is lap top or desk top programmable. The unit allows you to tune 31 points on your maf transfer function
Jim Gonzales [sales@pro-flow.com]
so that would = $1134
Re: Ok the MAF topic again - limits. maf tuner maf tuner bingo! put any hz vs g/second function you want (i.e. cut whatever it reports by half) into long as they are talking about for gms and not for mustangs, in which case it still wouldnt work 
i'll have to investigate tomorrow.
edit... looks like they put a ford part in the gm section there.. wonder what they are talking to you about.. the laptop programmable tuner in the gm section clearly shows modifying voltage, not frequency.
i'll have to investigate tomorrow. edit... looks like they put a ford part in the gm section there.. wonder what they are talking to you about.. the laptop programmable tuner in the gm section clearly shows modifying voltage, not frequency.
TECH Addict
Joined: Nov 2001
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From: College Station, Tx
Re: Ok the MAF topic again - limits. I just finished a circuit out here that will convert a ford style maf over to a GM input - it looks great on the scope but I will have to test it out on my car before I know for sure. It's pretty simple and should cost a good bit less than 390 bucks 
.
There is really no need for a separate tuner component as you can tweak the function in your pcm to report whatever you want, and the frequency out put can be set to whatever in the converter.
The problem with extending the stock style units is that their calibration, precision, and accuracy is unknown vor frequency outputs above stock. With the pro-m maf you get a calibration sheet with it (for a few extra bucks). If someone wanted to send off a stock maf then you could have an idea to what frequency it is actually good to.
If someone wanted to do that it would be simple to make a device that mapped the extended frequency map into the stock frequency range, and then just re-calibrate in the pcm.
. There is really no need for a separate tuner component as you can tweak the function in your pcm to report whatever you want, and the frequency out put can be set to whatever in the converter.
The problem with extending the stock style units is that their calibration, precision, and accuracy is unknown vor frequency outputs above stock. With the pro-m maf you get a calibration sheet with it (for a few extra bucks). If someone wanted to send off a stock maf then you could have an idea to what frequency it is actually good to.
If someone wanted to do that it would be simple to make a device that mapped the extended frequency map into the stock frequency range, and then just re-calibrate in the pcm.
Re: Ok the MAF topic again - limits.
If someone wanted to do that it would be simple to make a device that mapped the extended frequency map into the stock frequency range, and then just re-calibrate in the pcm.
maf--->tuner-------->pcm
HZ--->HZ->HZ/2--->HZ/2->g/s*2
pro m sells gm meters.. surely they have flowed one beyone 11,250hz for 98's and 12kz for 99+'s
Re: Ok the MAF topic again - limits. Admin here, maybe I make a suggestion. There are two issues here:
1) Total cost of a MAF solution
2) Ranking of the best MAF solution
I’d like one of you guys to find one of our sponsors to carry the product, and give the first 5 guys a break so as to help the shop do a buy-in, but also reward you for taking the plunge.
I’m sorry but $1100 for a MAF solution is bogus. It’s too pricey. The TSI Interceptor piggyback pcm is $1000 from Mac.
Let me know if I can help but perhaps one of the FI-oriented shops can work out a deal for the guys.
PSJ
1) Total cost of a MAF solution
2) Ranking of the best MAF solution
I’d like one of you guys to find one of our sponsors to carry the product, and give the first 5 guys a break so as to help the shop do a buy-in, but also reward you for taking the plunge.
I’m sorry but $1100 for a MAF solution is bogus. It’s too pricey. The TSI Interceptor piggyback pcm is $1000 from Mac.
Let me know if I can help but perhaps one of the FI-oriented shops can work out a deal for the guys.
PSJ
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Verdad Gallardo Re: Ok the MAF topic again - limits. I had a very long call with the head engineer at Pro -M and I think they will become a sponsor.
We talked about doing a GP so I think we can get something going in the next 30 days. It was a very cool conversation they are doing a lot of stuff now with LS1 cars.
We talked about doing a GP so I think we can get something going in the next 30 days. It was a very cool conversation they are doing a lot of stuff now with LS1 cars.
Re: Ok the MAF topic again - limits. did they say wether or not the maf tuner the list in the gm section is specifically for the gm maf or not? and what the adjustment parameters are?
Re: Ok the MAF topic again - limits. We mostly talked about Pro-M and it's history making custom "meters" but we also talked about a MAF for the 500-700 hp guys.
They do have a MAF tuner it can calibrate for different things but I don't recall all the parameters.
They do have a MAF tuner it can calibrate for different things but I don't recall all the parameters.
9 Second Club
Joined: Nov 2001
Posts: 1,445
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From: Bay Area, CA
Re: Ok the MAF topic again - limits.
just emailed Prom and got this reply on how to get a higher MAF meter.
Hi, I have a turbocharged LS1, and am trying to get past the limited 62lb/min GM MAF meter.
I see you have a conversion box to equip the GM cars with pro-m ford MAF meters. What all is involved in doing the swap, or which components are needed, and their cost. WHat is the mhz limits of these componets.
A few others along with myself are interested in increasing the capablities of the ls1 MAF for FI applications.
thanks.
We make two boxes, standalone, one is a calibrator that allows you to adjust the meter that is on the car, we also sell a converter that allows the Ford MAF to work on a GM vehicle. Cost of the calibrator is $445. Cost of the Converter is $390. We also have an new MAF tuner which lists for $299 which is lap top or desk top programmable. The unit allows you to tune 31 points on your maf transfer function
Jim Gonzales [sales@pro-flow.com]
so that would = $1134
Hi, I have a turbocharged LS1, and am trying to get past the limited 62lb/min GM MAF meter.
I see you have a conversion box to equip the GM cars with pro-m ford MAF meters. What all is involved in doing the swap, or which components are needed, and their cost. WHat is the mhz limits of these componets.
A few others along with myself are interested in increasing the capablities of the ls1 MAF for FI applications.
thanks.
We make two boxes, standalone, one is a calibrator that allows you to adjust the meter that is on the car, we also sell a converter that allows the Ford MAF to work on a GM vehicle. Cost of the calibrator is $445. Cost of the Converter is $390. We also have an new MAF tuner which lists for $299 which is lap top or desk top programmable. The unit allows you to tune 31 points on your maf transfer function
Jim Gonzales [sales@pro-flow.com]
so that would = $1134
Re: Ok the MAF topic again - limits. We talked about a custom MAF for FI cars that might list at $600. You would not need anything else as far as a harness goes, no more parts.
I challenged him on the $1130 number and he said that it might a combination of different things.
I challenged him on the $1130 number and he said that it might a combination of different things.
TECH Apprentice
Joined: Apr 2002
Posts: 308
Likes: 0
From: Austin, TX
Re: Ok the MAF topic again - limits.
We talked about a custom MAF for FI cars that might list at $600. You would not need anything else as far as a harness goes, no more parts.
I challenged him on the $1130 number and he said that it might a combination of different things.
I challenged him on the $1130 number and he said that it might a combination of different things.
TECH Addict
Joined: Nov 2001
Posts: 2,207
Likes: 0
From: College Station, Tx
Re: Ok the MAF topic again - limits. http://www.slowcar.net/MAF%20Circuit.jpg
That is the circuit I made to turn a 0-5V signal into a 0-12KHz signal (you can actually adjust the potentiometer to get from about 0-10kHz to 0-14kHz so it will work for LT1's and all LS1's).
The one I built was linear V-F to less than 0.01%. I used a LM131 since it is a metal can chip and should have better EMI rejection, but you can substitute in a LM231 or 331 as they are all pin compatible.
You just need a DVM and a frequency counter to adjust your response curve (and log it) - then get the PRO-M maf (Univer + would be my suggestion) with their airflow -> voltage conversion. You can then use your function you measure above to setup your calibration table. For values over 512 g/sec just use the scaling trick for massflow, injector, and displacement. You can then use a calculated PID in EFI Live so you see the correct values in real time.
The circuit gives a nice 0-5V square wave output (you can set it to whatever you want by changing the 5v regulator) and Ton = Toff. The 12V regulator can actually be just about anything up to 40V - it just has to be higher than the max voltage you are measuring (5v). The 12V regulator isn't totally required, but I think it's a good idea. with a 6v-20v spread I frequency change was below the resolution of my scope (essentially 0).
I am going to get some PCB's made up when I get pack, and SpeedDemon will probably be carrying them - but if you want you can make the circuit yourself if you want to -it's not very complicated. The mm74C74 is just a /2 flip-flop to give me a nice square wave and fix the DC at 50%. Any comparable part should work also, this is just what i had available.
That is the circuit I made to turn a 0-5V signal into a 0-12KHz signal (you can actually adjust the potentiometer to get from about 0-10kHz to 0-14kHz so it will work for LT1's and all LS1's).
The one I built was linear V-F to less than 0.01%. I used a LM131 since it is a metal can chip and should have better EMI rejection, but you can substitute in a LM231 or 331 as they are all pin compatible.
You just need a DVM and a frequency counter to adjust your response curve (and log it) - then get the PRO-M maf (Univer + would be my suggestion) with their airflow -> voltage conversion. You can then use your function you measure above to setup your calibration table. For values over 512 g/sec just use the scaling trick for massflow, injector, and displacement. You can then use a calculated PID in EFI Live so you see the correct values in real time.
The circuit gives a nice 0-5V square wave output (you can set it to whatever you want by changing the 5v regulator) and Ton = Toff. The 12V regulator can actually be just about anything up to 40V - it just has to be higher than the max voltage you are measuring (5v). The 12V regulator isn't totally required, but I think it's a good idea. with a 6v-20v spread I frequency change was below the resolution of my scope (essentially 0).
I am going to get some PCB's made up when I get pack, and SpeedDemon will probably be carrying them - but if you want you can make the circuit yourself if you want to -it's not very complicated. The mm74C74 is just a /2 flip-flop to give me a nice square wave and fix the DC at 50%. Any comparable part should work also, this is just what i had available.
Re: Ok the MAF topic again - limits. http://www.slowcar.net/MAF%20Circuit.jpg
That is the circuit I made to turn a 0-5V signal into a 0-12KHz signal (you can actually adjust the potentiometer to get from about 0-10kHz to 0-14kHz so it will work for LT1's and all LS1's).
The one I built was linear V-F to less than 0.01%. I used a LM131 since it is a metal can chip and should have better EMI rejection, but you can substitute in a LM231 or 331 as they are all pin compatible.
You just need a DVM and a frequency counter to adjust your response curve (and log it) - then get the PRO-M maf (Univer + would be my suggestion) with their airflow -> voltage conversion. You can then use your function you measure above to setup your calibration table. For values over 512 g/sec just use the scaling trick for massflow, injector, and displacement. You can then use a calculated PID in EFI Live so you see the correct values in real time.
The circuit gives a nice 0-5V square wave output (you can set it to whatever you want by changing the 5v regulator) and Ton = Toff. The 12V regulator can actually be just about anything up to 40V - it just has to be higher than the max voltage you are measuring (5v). The 12V regulator isn't totally required, but I think it's a good idea. with a 6v-20v spread I frequency change was below the resolution of my scope (essentially 0).
I am going to get some PCB's made up when I get pack, and SpeedDemon will probably be carrying them - but if you want you can make the circuit yourself if you want to -it's not very complicated. The mm74C74 is just a /2 flip-flop to give me a nice square wave and fix the DC at 50%. Any comparable part should work also, this is just what i had available.
That is the circuit I made to turn a 0-5V signal into a 0-12KHz signal (you can actually adjust the potentiometer to get from about 0-10kHz to 0-14kHz so it will work for LT1's and all LS1's).
The one I built was linear V-F to less than 0.01%. I used a LM131 since it is a metal can chip and should have better EMI rejection, but you can substitute in a LM231 or 331 as they are all pin compatible.
You just need a DVM and a frequency counter to adjust your response curve (and log it) - then get the PRO-M maf (Univer + would be my suggestion) with their airflow -> voltage conversion. You can then use your function you measure above to setup your calibration table. For values over 512 g/sec just use the scaling trick for massflow, injector, and displacement. You can then use a calculated PID in EFI Live so you see the correct values in real time.
The circuit gives a nice 0-5V square wave output (you can set it to whatever you want by changing the 5v regulator) and Ton = Toff. The 12V regulator can actually be just about anything up to 40V - it just has to be higher than the max voltage you are measuring (5v). The 12V regulator isn't totally required, but I think it's a good idea. with a 6v-20v spread I frequency change was below the resolution of my scope (essentially 0).
I am going to get some PCB's made up when I get pack, and SpeedDemon will probably be carrying them - but if you want you can make the circuit yourself if you want to -it's not very complicated. The mm74C74 is just a /2 flip-flop to give me a nice square wave and fix the DC at 50%. Any comparable part should work also, this is just what i had available.
