Belows 14 psi=no fuel computer?
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Belows 14 psi=no fuel computer?
I am going non sequantial in a couple of weeks and I am gathering up the parts. The car has a greddy intake, greddy IC with the elbow (no bov flange), and will be complemented with a midpipe and DP along with a 3" exhaust. Clutch and other parts will also be upgraded. What bothers me is that the mechanic, a good one, told me that below 14psi, there is no need to upgrade injectors, pump or the computer. I believe him, but I have doubts about this. Any input on this. I am at 3000 ft of altitude more or less if it matters.
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Beside you will hit fuel cut at 12 psi. from all the mods that you are listing, you will need an Boost controller to keep the spikes down or you will be buying a new motor GUARANTEE!!!! A PFC is a good recommendation also.
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BUMP for more info. Yes, I have a Greddy Profec boost controller to aid with the boost spike.
#6
are you talking 14psi of absolute pressure or guage pressure. The reason that I am asking at altitud there is a difference. I am 6k feet, colorado and guage psi of 14 is 11 psi of absolute pressure from every single datalog that I have seen on varius cars. There is an atmospheric pressure difference with altitud.
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I question the fuel cut at 12psi. My FD is stock (meant to be stock) after purchasing it, I got a boost gauge and it was running 12 psi, spiking to 14psi, yet didn't hit fuel cut... do I come to the conclusion that I have a remapped ECU?
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is your car a jap model? it might have a fuel cut defender installed by the previous owner.
#10
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The problem is that the larger spikes can occur which are dangerous. They can happen quickly during that "allowed" time and cause damage. If you are able to sustain 14 PSI, then someone has removed fuel cut from your car. If you are just spiking to 14 PSI, that should be controlled with an electronic boost controller as the stock computer will not account for spikes.
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Mahjik, just the person I was hoping to respond I remember with my 1st 3rd gen, I did not hit any type of fuel cut and it would spike up to 15 psi for over 10 seconds, and I assume it would continue at 15 if I did not let go of the throttle.
Norbak, my mechanic, I assume is talking about gauge psi, not absolute. He is in Albuquerque, which is at an even higher altitude than El Paso. He is a competent mechanic, and many people can vouch for that, which is what bothers me cause I keep reading about fuel cut above 12psi and how dangerous it could be to let the stock ECU handle that much boost without extra fuel.
Would it be wise to buy a remapped ECU from pettit and raise the boost to lets say 15? Upgrade my fuel pump and maybe the injectors?
Thanks guys.
To control boost, like I said, I am installing the Greddy profec b spec II.
Norbak, my mechanic, I assume is talking about gauge psi, not absolute. He is in Albuquerque, which is at an even higher altitude than El Paso. He is a competent mechanic, and many people can vouch for that, which is what bothers me cause I keep reading about fuel cut above 12psi and how dangerous it could be to let the stock ECU handle that much boost without extra fuel.
Would it be wise to buy a remapped ECU from pettit and raise the boost to lets say 15? Upgrade my fuel pump and maybe the injectors?
Thanks guys.
To control boost, like I said, I am installing the Greddy profec b spec II.
#12
Racecar - Formula 2000
Fuel-Cut Boost Values
See attached...
#15
Mr. Links
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Mahjik, just the person I was hoping to respond I remember with my 1st 3rd gen, I did not hit any type of fuel cut and it would spike up to 15 psi for over 10 seconds, and I assume it would continue at 15 if I did not let go of the throttle.
Norbak, my mechanic, I assume is talking about gauge psi, not absolute. He is in Albuquerque, which is at an even higher altitude than El Paso. He is a competent mechanic, and many people can vouch for that, which is what bothers me cause I keep reading about fuel cut above 12psi and how dangerous it could be to let the stock ECU handle that much boost without extra fuel.
Would it be wise to buy a remapped ECU from pettit and raise the boost to lets say 15? Upgrade my fuel pump and maybe the injectors?
Thanks guys.
To control boost, like I said, I am installing the Greddy profec b spec II.
Norbak, my mechanic, I assume is talking about gauge psi, not absolute. He is in Albuquerque, which is at an even higher altitude than El Paso. He is a competent mechanic, and many people can vouch for that, which is what bothers me cause I keep reading about fuel cut above 12psi and how dangerous it could be to let the stock ECU handle that much boost without extra fuel.
Would it be wise to buy a remapped ECU from pettit and raise the boost to lets say 15? Upgrade my fuel pump and maybe the injectors?
Thanks guys.
To control boost, like I said, I am installing the Greddy profec b spec II.
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Not a remapped ECU, or at least the previous owner did not list that in his list of mods. However, I will do a check.
BTW, I called Pettit, and asked if they had a remapped ECU and they did, but they had a 94 ECU, my car is a 95. Can my car run on the 95 ECU?
BTW, I called Pettit, and asked if they had a remapped ECU and they did, but they had a 94 ECU, my car is a 95. Can my car run on the 95 ECU?
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https://www.rx7club.com/3rd-generation-specific-1993-2002-16/help-bought-pettit-ecu-410197/
The main issue with the '94 is the EGR. I don't remember if the 95's have the electronic controlled EGR or not (I'm sure someone will pipe in here with the answer). If it doesn't, then you'll get an EGR code from the 94 ECU. If it does have the electronic controlled EGR, then you'll be fine.
#18
Mazda should have setup up an iginition cut followed by a delayed fuel cut to prevent the lean conditions associated with fuel cut.
I'm assuming the PFC allows you to control both of these values much the way the EMS does?
I'm assuming the PFC allows you to control both of these values much the way the EMS does?
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I called Pettit again, and Cam said it would not be adviceable to use a 94 ECU on a 95 vehicle. I migh just pony up a few more dollars and get the PFC.
Now, since I am getting the PFC, and I am keeping my stock twins, would it be wise to upgrade the fuel pump and injectors along with it? I plan to up the boost to 15psi.
LOL, 1st I said I only wanted to fix things, now I have PFC, wideband, and wanting to use more boost. How easily projects change.
Now, since I am getting the PFC, and I am keeping my stock twins, would it be wise to upgrade the fuel pump and injectors along with it? I plan to up the boost to 15psi.
LOL, 1st I said I only wanted to fix things, now I have PFC, wideband, and wanting to use more boost. How easily projects change.
#23
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I went from a straight reman swap out, to a ported rebuild with about 4k in goodies on top of that, and the list keeps getting longer and longer.
It's so addicting, it's scary. Atleast I'm staying modest and tasteful on my upgrades, I can't imagine how expensive it would get if I was going for big gains.
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LOL, I know what you mean. Initially, I was just going to fix the boost problem, now I have volk wheels, tein flex, launch kit, radiator...etc...so far its over 4k...and I still need to order the4 damn clutch...ouch. Gotta pay to play I guess.
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