MPI MSP car now running 21psi
- Thread starter MPNick
- Start date
jrodhotrod
Contributor
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- 2003 Mazda Protege5 (Mine) 2002 Nissan Sentra GXE (Wife's)
PM Me.KzA said:
I'll have my stock Mazdaspeed turbo with 28,000 miles on it for sale very soon. In perfect working order has never seen over 9.5 psi.
-Jared
KzA said:
i know of a couple people running blow by mafs right now and they have had no problems. Brianmp5t for one.
Also, with the haltech there is no need for a maf at all, i have a 3 bar map sensor that will fine tune better than any maf ever could.
Im just curious about whp and stock injectors.
-B
MPNick said:
funny you mention this. I was just talking about this with one of your distributor friends here in clinton township michigan. He owns a shop called API racing where my manifold is getting done right now. His name is Mark, he seemed to know you.
We were discussing maf vs. map and he said that he uses a form of the perfect power unit, the smt-6, to tune his shelby. he said that dealing with maf's is a pain and a lot harder to tune in comparison to a absolute manifold pressure set up.
He also told me some interesting info about the mpi tuner. It went something along the lines of "it is the same thing as the smt-6 but just configured a little differently".
He said that he could distribute the same thing you do for proteges to shelby owners or the like. Basically the mpi tuner according to him is no huge thing, it is just a box marked MPI tuner that is essentially the perfect power smt-6.
That is fine and if it works for the proteges then it works for the proteges. I just think it would be nice to be a bit more upfront about the system being used (perfect power) vs ("mpi tuner").
Anywho back on track, he did say you are a very knowledgeable man and know your stuff. I definately trust his word and I hae before already said that I think you are doing a lot of good for the protege community.
Basically, he said if he could go with a map set up for his car instead of a maf he would.
My statement about maps being able to be fine tuned better then maf's may have been a bit out of line, but it was the impression i got when speaking with mark today.
Correct me where i am wrong, i would actually like to learn a bit more about it.
-B
Here is a bit of info i found on maf vs. map. Seems as though they both have pros and cons.
"""""So which is better, MAP or MAF?
While Air-Flow systems are still favored by most manufacturers due to their accuracy, speed-density systems are slowing gaining favor once again due to advances in electronic engine management. In order for a speed-density (MAP) based system to offer the accuracy in A/F ratios to pass the stringent vehicle certification tests, advanced ECU technology must be used to cope with the speed-density's inability to optimally handle transient driving conditions (compared to an air-flow system).
Starting in 2000, Subaru went to a sophisticated speed-density system in the North American market while retaining the air-flow system for their turbocharged Impreza, Legacy and Forester applications sold overseas. We can only make assumptions as to Subaru's reason for switching to speed-density but our guess is was done to reduce cost while improving reliability. Also making guesses, we expect you'll see the air-flow system return when the WRX is introduced here in the US though the non-turbo applications will most likely retain their speed-density system as thus far it's proven very reliable. Why not use the speed-density on the WRX? Our assumption is based on the fact that Subaru has been using the air-flow system quite reliably in other countries and as there will be no major drivetrain/engine changes for the next generation WRX, they might not want to incur the added development costs involved in making a speed-density WRX pass the tough US emission certification tests. Again, these are just assumptions. We'll find out for sure next year.
The facts remain the same though, the air-flow systems are slightly more accurate at calculating proper Air/Fuel ratio under a wider variety of driving conditions. At Wide Open Throttle (WOT) though, they are both very similar. It's primarily under transient conditions (partial throttle changes/city driving) where they differ the most. Again, the differences are primarily in theory and hardly sometime you'll notice by the seat of your pants. Those of you with speed-density systems don't think your system needs to be improved by going to a air-flow setup. Keep this comforting thought in your head; nearly every aftermarket engine management system uses a speed-density system (ie: Haltech, TEC II, Motec, EFI, etc.)."""""""
it seems as if both have their pros and cons.
I stand corrected.
-B
"""""So which is better, MAP or MAF?
While Air-Flow systems are still favored by most manufacturers due to their accuracy, speed-density systems are slowing gaining favor once again due to advances in electronic engine management. In order for a speed-density (MAP) based system to offer the accuracy in A/F ratios to pass the stringent vehicle certification tests, advanced ECU technology must be used to cope with the speed-density's inability to optimally handle transient driving conditions (compared to an air-flow system).
Starting in 2000, Subaru went to a sophisticated speed-density system in the North American market while retaining the air-flow system for their turbocharged Impreza, Legacy and Forester applications sold overseas. We can only make assumptions as to Subaru's reason for switching to speed-density but our guess is was done to reduce cost while improving reliability. Also making guesses, we expect you'll see the air-flow system return when the WRX is introduced here in the US though the non-turbo applications will most likely retain their speed-density system as thus far it's proven very reliable. Why not use the speed-density on the WRX? Our assumption is based on the fact that Subaru has been using the air-flow system quite reliably in other countries and as there will be no major drivetrain/engine changes for the next generation WRX, they might not want to incur the added development costs involved in making a speed-density WRX pass the tough US emission certification tests. Again, these are just assumptions. We'll find out for sure next year.
The facts remain the same though, the air-flow systems are slightly more accurate at calculating proper Air/Fuel ratio under a wider variety of driving conditions. At Wide Open Throttle (WOT) though, they are both very similar. It's primarily under transient conditions (partial throttle changes/city driving) where they differ the most. Again, the differences are primarily in theory and hardly sometime you'll notice by the seat of your pants. Those of you with speed-density systems don't think your system needs to be improved by going to a air-flow setup. Keep this comforting thought in your head; nearly every aftermarket engine management system uses a speed-density system (ie: Haltech, TEC II, Motec, EFI, etc.)."""""""
it seems as if both have their pros and cons.
I stand corrected.
-B
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505zoom said:
Yeah i was just searching for that. I guess i just wasnt really paying attention to all of this.
I know Nicks' stuff works and is a good unit for the proteges.
I was just always under the impression map was better than maf. I know dsm guys run gm mafs and maf translators for big power.
I guess ultimately it is up to the end user.
-B
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ddogg777 said:
All third gen Proteges use the same fuel pump. The MSP mentioned is running extra injectors to deal with fuel...It doesn't put as much of a strain on the stock pump becuase they are not running all the time.
I was under the impression that the fuel pump is always running. The fuel regulator is what puts the strain on the pump because it keeps the pressure at 43psi and releases the excess. If anything, having the injectors open would put less strain on the pump because the pressure would drop as the fuel flows through. Correct me if I'm wrong.StuttersC said:
I do understand that extra injectors will allow more fuel in at a lower pressure so I know the fuel pump doesn't have to fight a RRFPR (assuming Dean isn't using one of these). I just thought that the stock pump didn't flow enough due to small fuel lines or whatever. But evidently, it does, SWEET!
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- ‘19 CX-5 GTR Tu
Feul pump is alwayz on. And yes..a fuel pressure regulator like the rrfpr will add stress to the stock fuel pump.ddogg777 said:I was under the impression that the fuel pump is always running. The fuel regulator is what puts the strain on the pump because it keeps the pressure at 43psi and releases the excess. If anything, having the injectors open would put less strain on the pump because the pressure would drop as the fuel flows through. Correct me if I'm wrong.
I do understand that extra injectors will allow more fuel in at a lower pressure so I know the fuel pump doesn't have to fight a RRFPR (assuming Dean isn't using one of these). I just thought that the stock pump didn't flow enough due to small fuel lines or whatever. But evidently, it does, SWEET!
Dean is not using a RRFPR. He is using the mpi tuner & extra injecotrs.
Stock fuel pump works fine..the reason why companies like Flyin Protege offered the inline fuel pump..was due to the huge increase in feul pressure the RRFPR created..which stressed out oem fuel pumps.
Chas
The MPI is based off the SMT6, but Nick has different SW made specifically for him to use with our setups. He has different HW versions to work with our setups and also perfect power will allow a vendor to just slap their name on thier standard product if they want. Nick is not doing this, he has specific parameters changed to the units to make them so different that you cannot purchase one directly from perfect power. It is a Modern Performance Inc. unit that was made by perfect power.
As for MAF vs MAP, I don't know too much about them, but the car manufacturer's went to the MAF's for a reason, and that is better tunability. I'm sure the MAP setup works and all, but there is too much compensation needed for all types of environments and altitudes that the MAF setup will not need to do.
Dean is running an 80mm MAF and would not be able to produce the power he is without it. Well maybe he could, but it would be harder. The 80mm will flow tons more air than the stocker, it's a monster.
As for MAF vs MAP, I don't know too much about them, but the car manufacturer's went to the MAF's for a reason, and that is better tunability. I'm sure the MAP setup works and all, but there is too much compensation needed for all types of environments and altitudes that the MAF setup will not need to do.
Dean is running an 80mm MAF and would not be able to produce the power he is without it. Well maybe he could, but it would be harder. The 80mm will flow tons more air than the stocker, it's a monster.
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I was wondering about this option. I remember you guys had mentioned it before, but I really haven't heard much since.Bigg Tim said:
How does the 80mm MAF help? I know it flows more air, but does the MPI Tuner compensate for the voltages?
How do I say this? The stock ECU wants 0-5 volts, right? Does the 80mm MAF run the same voltage range? If so, would that mean the scale is different between the stocker and the 80mm version?
Say the stocker shows 4 volts at a given air flow. How much air is really flowing at the same 4 volts on the 80mm version? And does the MPI adjust the fuel accordingly (automatically), or do you have to tune for it?
I think I'm just a little confused on why the 80mm MAF is so much better when the ECU doesn't like anything over ~4.9 volts...I'm missing something I think.
You have to tune the 80mm, so it's a little more work. The ECU will still only want to see up to it's limits but I believe that, like you said, x amount of volts on the stock MAF may be less volts on the 80mm so you have more of a range to tune. I don't know this for fact, so Nick will have to go more into that.
You still can never go over 5.0 volts. You do tune for the bigger MAF. Flow is flow. When you try to flow more air then the stock MAF can handle you get a pressure drop across the meter. Now the small meter is costing you power. Some reach the limit of the stock MAF sooner then others. It is not cause by how much boost you are running it is caused by how much air flow you are moving. Big Tim was making around 230 whp @8 psi with a clean 4th gear pull. Look at others and you will see that they are running much higher boost levels to make the same power or even alot less power. Big Tim is running the MPI turbo system. It can make more whp per lbs of boost then most system, because it is well made.StuttersC said:
An engine is a hot air pump. The more air and the cooler the air is going into the engine will get you more power.
Thanks again
Later....Nick
