Just a quick one, would I require a remap if I was to fit an external swirl pot and Bosch pump? I\'m currently running a gtr in tank pump and aeromotive FPR
Cheers
No you shouldn\'t need a remap as you have control of the fuel pressure, the injectors aren\'t injecting more fuel each cycle but with an 044 they get a more reliable fuel supply to support additional fueling if needed.
Quote from: m1tch;853701No you shouldn\'t need a remap as you have control of the fuel pressure, the injectors aren\'t injecting more fuel each cycle but with an 044 they get a more reliable fuel supply to support additional fueling if needed.
Cheers buddy I did think that just needed a second opion
Just make a note of your Fuel pressure before you start and as long as that remains the same you should be fine.
hmmm
I would say yes you would need a remap , even though you have the same fuel base pressure setup on the FPR , in my experiance going to a different pump, in this case an 044 I have found the tune has gone richer on boost when mapping FDs.
Remember different fuel pumps have different flow rates at different pressures
But surly the volume of fuel going round won\'t make any difference if the rail pressure remains the same and the Injector pulse is the same? This is assuming the GTR pump is in its Comfort zone and the rail pressure is not dropping off.
it does make a difference, its the same mistake when people think of boost pressure eg 10 psi on two different size turbos, the volume of air being delivered to the engine is different.
I have been through four different fuel setups on my own car, when going to a bigger pump the whole map richend up by a whole point in AFR across the whole map in my experiance.
Done countless remaps of peoples cars, when they have upgraded the pump the map gets richer.
How much more flow the 044 over the GTR pump will give an indication if the map will richen up
my analogy with boost maybe incorrect to use as an example in this case eg Gas is more compressable then liquid
So just go back to what I have experianced , changing any part of the fuel system in my experiance has always changed the AFRs seen on "boost" not so much on cruise, due to the smaller pump dropping fuel pressure at high loads.
So Grizzly is correct if the same fuel pressure is maintained at the different load points and the injector timings are the same, afr will be the same
But when a tuner has mapped before with the smaller pump and fuel pressure is dropping they have compensated using bigger injector timings on the higher loads to get the correct AFR, you will find when putting a bigger pump with the same base pressure on the higher loads it will get richer as pressure is not dropped. My advice when changing any fuel component get the map and afrs checked just in case (you might get a dodgy part or part not performing as expected) it could mean your engine.
Just have it checked to be sure, you will only have to pay for the time spent checking/sorting the fuel map and not a fuel remap session.
You will be able to tell if the car is running richer with the new pump as it will stink of petrol and give more flammage especially on over run up to traffic lights:D
Also you will have less mpg if its rich.
Cheers for the reply\'s, I\'m gonna check the fuel pressure before i hard wire the in tank pump and do the same before fitting the swirl and Bosch pump. I\'ll give it a run down to carl for a map check just to be safe
You\'ll know if its running rich it will make your eye\'s Sting and you bank manager Cry :)
WTF!?
You don\'t have to check anything! You never need a remap if u change your fuel pump!
Only needed when you change the injectors!!
have a nice day.
Quote from: Benny;854956WTF!?
You don\'t have to check anything! You never need a remap if u change your fuel pump!
Only needed when you change the injectors!!
have a nice day.
Well if thats true, why would you need to upgrade the pump in the first place?
Quote from: philiwily;854959Well if thats true, why would you need to upgrade the pump in the first place?
because the risk of; not supporting the injectors with enough fuel = fuel cut; is very high, with the OLD genuine pump
it\'s not even necessary to UPGRADE the pump, you can even change against a new genuine one...
but if you\'re going to have more hp anyways then take one that provides more fuel ;)
Not supporting enough fuel to the injectors isn\'t fuel cut, and if your going to have more hp after changing your pump it would only be because your previous pump was providing insufficient flow to start with which would warrant a check of the map.
I\'ve done quite a bit of mapping but if Blitzboy, who has a lot more experience of mapping, comes along and says he has experienced something I would take it on board.
if you have a fuel pump with insufficient flow you could suffer from fuel cut at higher rev\'s, that\'s what I was trying to say.
still, mapping after a fuel pump change is BULL:censored::censored::censored::censored:.
the injectors won\'t inject more fuel because of the stronger fuel pump...
Depends if you have an adjustable FPR or not Benny, if you need a remap or not, if you are using the stock non adjustable fpr then the better fuel pump WILL give you increased fuel pressure and you WILL be running richer.
But changing any part of the fuel system I would advise anyone to get the AFRs checked on the rolling road just in case, just to be safe.
oh man come on... why should the fuel pressure increase if you leave the stock fpr in it?
the fpr regulates the pressure... like it\'s name already says it, so why should the pressure go up?? the fpr doesn\'t break, give up, or what ever because of the stronger fuel pump..!?
Surely it all boils down to do you want to chance blowing it up and the cost of an engine rebuild over the small cost of a tweak and remap.... Too many people try to cut corners these days... Why even change the pump if your not going to remap??
Quote from: Benny;854997oh man come on... why should the fuel pressure increase if you leave the stock fpr in it?
the fpr regulates the pressure... like it\'s name already says it, so why should the pressure go up?? the fpr doesn\'t break, give up, or what ever because of the stronger fuel pump..!?
oh man do some more reading, or is it just stuff you read off the internet!!!
the stock FPR on system is designed with the specific pump and flow rate in mind dude!!!!!!!! when putting a higher flow pump which flows more the fuel pressure goes up , as you have not changed the diagprham spring pressure its fixed!
By your logic Man , there is no point in buying aftermarket adjustable FPRs LOL
Also seeing as I have mapped over 100 of these bloody RX7s and know what happens in reality
Also the stock FPR and FPD will fail over time if you put too big a pump on them
So what happens with a stock fpr with fixed preload on the spring and a bigger pump it cannot flow enough excess fuel back to the tank therefore fuel pressure goes up, if it was adjustable then you can slacken off the preload spring to maintain correct base pressure and the excess fuel can go back to tank
Any change to the fuel system if DIY is worthy of a quick check over by a person that maps rotaries. A bit of cash is better than a rebuild, plus you can always get more boost in there:) which is always a bonus.
If Benny still is not convinced, here some info from AEM themselves, explaining it in different words
"Other "universal" regulators incorporate a fixed discharge orifice that does not allow users to control fuel flow if the fuel pump is different than stock. In cases where a larger fuel pump is used for high-horsepower applications, a regulator that has too small of a discharge orifice will not allow fuel to be bypassed when the vacuum in the top chamber is increased. This causes a momentary rich condition that, depending on the severity, can cause an engine to stumble or stall. On street cars, this condition could degrade catalytic converter performance. On the flip side, if the discharge orifice is too large it can make controlling fuel pressure within the regulator difficult since small changes to the setscrew can affect large changes in fuel pressure. A too-large orifice can also cause fuel pressure to "hunt" during fluctuating throttle conditions, which can cause a momentary lean condition. That could spell disaster in the form of detonation, which is a turbocharged car\'s worst enemy."