yet another fueling question

[s00045732]

hi, i searched for an answer but couldnt really find one or at least a definate one.........
 
aim- wheel powers of around 300-320ish
 
as is- stock twins (proberly will go non-sequential), decat straight through 3inch exhaust, dragonperformance vmount and rad, apexi power fc+comander, and boost controller not yet fitted
 
i was goin to go and get 850 cc primarys and 1680cc secondries (as i was offer these with rails to match) with supra tt fuel pump, but is this total overkill for the power i want to achieve?
 
also i was told 850\'s all round were hard to get a good map from, is there any truth in this? the car will be 100% track drift car if that makes any differences...
 
thanks in advance
 
Paul

[lee mills]

Total overkill for that amount of power. Iwas running 507 @ the fly with 550 primaries and 1000 secondaries.

[s00045732]

well fair enough, is the standard fuel setup suitable for that kind of power or should i be thinking of uprating the fuel pump or secondry injectors in some way? thanks for the quick reply

[SiH]

I went for 1680\'s, KGParts rail, Walbro pump, and Aeromotive FPR.

With very similar mods to you, I previously hit 343 atf, 290 something ATW, but 94% duty.
Fitted the fuel upgrades and now make 363 atf, just over 300 atw, peaking at avout mid 60\'s duty, and the car is MUCH more driveable

[Grizzly]

If it was me i\'d buy a really good fuel pump (Bosch 044 or Apexi BNR) then upgrade the Fuel Regulator (loose the Pulsation damper at the same time) and have the Injectors cleaned. That should run 300-310 whp. I think the key is buying a decent Fuel pump, the better ones actually flow what they claim and last forever.

The next step would be fitting 1600 Secondary\'s and that will be enough well into the 500\'s.

Difference between a stock Fd Pump and a 044

[Grizzly]

Don\'t forget if you are running Stock twins 320rwhp will be a level that the stock twins won\'t be able to maintain for long periods, Blowing allot of money on overkilling the Fuel system would only be worth while if you plan to fit Single turbo/Uprated Twins in the future.

[SiH]

If you are implying that the Walbro\'s are a bad pump I don\'t agree I\'m afraid - Lots of people use them, even Supra owners as an upgrade to the hallowed UK Spec JZA80 pump.
I know of S-bodies running into the 500\'s with them, skylines running big power, and I\'ve had 3 cars that have never had an issue on them.
They have a bad name from a dodgy fake batch a few years ago, and unfortuantely it seems to have stuck. They admittedly aren\'t that hot at higher pressures though.

I\'ve always been of the opinion that cranking up the fuel pressure isn\'t really the right way to do it, but I\'m over cautious, and like to over spec. I prefer to put bigger injectors in instead.

[Grizzly]

If you are implying that the Walbro\'s are a bad pump I don\'t agree I\'m afraid - Lots of people use them, even Supra owners as an upgrade to the hallowed UK Spec JZA80 pump.
I know of S-bodies running into the 500\'s with them, skylines running big power, and I\'ve had 3 cars that have never had an issue on them.
They have a bad name from a dodgy fake batch a few years ago, and unfortuantely it seems to have stuck. They admittedly aren\'t that hot at higher pressures though.

I\'ve always been of the opinion that cranking up the fuel pressure isn\'t really the right way to do it, but I\'m over cautious, and like to over spec. I prefer to put bigger injectors in instead.

I wasn\'t Implying anything but are you saying the Walbro is in the same leuge as the Apexi or Bosch? Lets put it this way i don\'t recall ever hearing about a Bad batch of Bosch 044\'s or a Apexi failing after two years of use.

Unfortunately you can\'t compare Supra parts next to Rx7, for some reason you don\'t get nearly as much power when using a similar set up. I would not take the cheaper option when it comes to Fuel/Coolant systems but that\'s just my Opinion.

I know what your saying about cranking up the Fuel pressure but the reason its not recommended is the Pulsation damper only just manages to handle stock pressure, loose that and fit a rise rate Fuel reg (so you don\'t get the Over fueling at low revs) and you are away.

[bnaellis]

hi, i searched for an answer but couldnt really find one or at least a definate one.........
 
aim- wheel powers of around 300-320ish
 
as is- stock twins (proberly will go non-sequential), decat straight through 3inch exhaust, dragonperformance vmount and rad, apexi power fc+comander, and boost controller not yet fitted
 
i was goin to go and get 850 cc primarys and 1680cc secondries (as i was offer these with rails to match) with supra tt fuel pump, but is this total overkill for the power i want to achieve?
 
also i was told 850\'s all round were hard to get a good map from, is there any truth in this? the car will be 100% track drift car if that makes any differences...
 
thanks in advance
 
Paul

850cc injector all round are fine mate. Get a cosmo pump or apexi skyline pump, and you can run stock fuel pressure for that power level as long as
you upgrade the fuel pump wiring so you bypass the ignition switch.


rgds
Brian

[trevtubby]

Just seen a thread which has Bosch 044 pumps for £110, think it was atomic rex selling them.

Get one bought, I will be! Bargain price.

[SiH]

I wasn\'t Implying anything but are you saying the Walbro is in the same leuge as the Apexi or Bosch? Lets put it this way i don\'t recall ever hearing about a Bad batch of Bosch 044\'s or a Apexi failing after two years of use.

I\'m not familiar with the tales of Walbro\'s failing after 2 years of use? the one I ran in my previous S14a was fine for the year and a half the previous owner had it, and the 2 and a half years I ran it. Nor in the year I\'ve had one in my FD at 360bhp. I can recall scant few (possibly 2?) cases of them failing in nearly 5 years associated with the 200SX tuning scene, with them being used in cars from standard spec to high power lag monsters, and race cars.
The \'dodgy batch\' was a huge anomaly, and in fact has been put down by many to be a batch of \'fake\' Walbros that somehow got into the supply chain.
I\'m aware of at least 2 failed Bosch 044\'s in the past year. Walbro\'s only seem to fail if they are run dry.

Unfortunately you can\'t compare Supra parts next to Rx7, for some reason you don\'t get nearly as much power when using a similar set up. I would not take the cheaper option when it comes to Fuel/Coolant systems but that\'s just my Opinion.

I\'m not trying to be deliberately argumentative here, but why can\'t you compare Supra parts - the part I was referring to was the Denso pump that many use as an upgrade for the FD. At the end of the day, a pump is driven by a voltage, and has to flow a set amount of fuel at a set pressure. Surely that\'s independant of the car it\'s on? It\'s not really got anything to do with the power being produced, it\'s purely fuel flow.

I know what your saying about cranking up the Fuel pressure but the reason its not recommended is the Pulsation damper only just manages to handle stock pressure, loose that and fit a rise rate Fuel reg (so you don\'t get the Over fueling at low revs) and you are away.

I was under the impression that the reason a lot of people don\'t like to ramp up the pressure is not due to the FPD, but the way in which injectors work. I\'m not even going to pretend to begin to understand how an injector works and what effects upping the FP has, but I was under the impression that there are recommended pressures that manufacturers specify? You\'re also putting more strain on the pump as well.

You don\'t need a RR fuel reg to stop overfuelling at low revs either, surely? A 1:1 is perfect. As long as the pump can flow enough at the pressure, the mapping is set for the FP, and the FPR can hold steady pressure, surely you don\'t have an issue?


Like I say, I\'m not saying everything I say is right, I\'m just trying to play devil\'s advocate at times, and get as much of an understanding as possible.
There\'s a stigma attached to useing a Walbro on this forum which is very odd, as like I say, they are used in a LOT of other tuning circles with no such tales attached to them.

[AtomicRex]

Im not taking sides on this, but the majority of people racing the Rx\'s are running the Bosch 044
 
We have a new batch coming in of these...I think I have 1 left at the moment.  So first come first servered as they say
 
Not sure on the spec of the Walbro...but the 044 flows 200l/h and maintains a pressure of 5bar but is good for 8bar.

[trevtubby]

Im not taking sides on this, but the majority of people racing the Rx\'s are running the Bosch 044
 
We have a new batch coming in of these...I think I have 1 left at the moment.  So first come first servered as they say
 
Not sure on the spec of the Walbro...but the 044 flows 200l/h and maintains a pressure of 5bar but is good for 8bar.

I would like one mate, but wont be until Sept. Will you have one available then? Also whats the price inc vat and delivery? Does it come with everything needed to fit it?

Ta

[Grizzly]

I\'m not familiar with the tales of Walbro\'s failing after 2 years of use? the one I ran in my previous S14a was fine for the year and a half the previous owner had it, and the 2 and a half years I ran it. Nor in the year I\'ve had one in my FD at 360bhp. I can recall scant few (possibly 2?) cases of them failing in nearly 5 years associated with the 200SX tuning scene, with them being used in cars from standard spec to high power lag monsters, and race cars.
The \'dodgy batch\' was a huge anomaly, and in fact has been put down by many to be a batch of \'fake\' Walbros that somehow got into the supply chain.
I\'m aware of at least 2 failed Bosch 044\'s in the past year. Walbro\'s only seem to fail if they are run dry.


I\'m not trying to be deliberately argumentative here, but why can\'t you compare Supra parts - the part I was referring to was the Denso pump that many use as an upgrade for the FD. At the end of the day, a pump is driven by a voltage, and has to flow a set amount of fuel at a set pressure. Surely that\'s independant of the car it\'s on? It\'s not really got anything to do with the power being produced, it\'s purely fuel flow.



I was under the impression that the reason a lot of people don\'t like to ramp up the pressure is not due to the FPD, but the way in which injectors work. I\'m not even going to pretend to begin to understand how an injector works and what effects upping the FP has, but I was under the impression that there are recommended pressures that manufacturers specify? You\'re also putting more strain on the pump as well.

You don\'t need a RR fuel reg to stop overfuelling at low revs either, surely? A 1:1 is perfect. As long as the pump can flow enough at the pressure, the mapping is set for the FP, and the FPR can hold steady pressure, surely you don\'t have an issue?


Like I say, I\'m not saying everything I say is right, I\'m just trying to play devil\'s advocate at times, and get as much of an understanding as possible.
There\'s a stigma attached to useing a Walbro on this forum which is very odd, as like I say, they are used in a LOT of other tuning circles with no such tales attached to them.

Anything you agree with then? The Walbro issues happened to me and they cost me an 4k so forgive me if i don\'t have faith in them.

[gillard28]

That walbro will flo enough for what you need.. i was running 20 psi on a heavy metha mix with this pump with no worries. the 044 is over kill.. if not go with what brian said
 
you dont need a pump that flows 8 bar so why use it.
 
scott