evildky Posted December 18, 2002 Share Posted December 18, 2002 where can I find a large as in about 255lph high pressure as in 90 to 100 psi, external fuel pump, best I can find is about $200 there has to be a better deal somewhere !? Quote Link to comment Share on other sites More sharing options...
MAYHEM Posted December 18, 2002 Share Posted December 18, 2002 Well, I think that's VERY reasonable.(read steal) for that price. Quote Link to comment Share on other sites More sharing options...
Guest Zcarsmakemyheadhurt Posted December 19, 2002 Share Posted December 19, 2002 I sell them for $100.00+ shipping... Alex Costa Precision Machined Engines 1-800-665-0405 Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted December 19, 2002 Share Posted December 19, 2002 MSD hp pump at Summit Racing $76.99 for the MSD pump, should be equivalent to the Walbro 255 hp pump. If you need more, buy two... Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted December 19, 2002 Share Posted December 19, 2002 Just curious. What are you doing that requires 100psi of fuel pressure? I am cutting back on the boost level I run by going with a different turbo but until recently I ran up to 26psi boost. With 43psi static FP, that amounts to only 69psi FP at full boost. Quote Link to comment Share on other sites More sharing options...
evildky Posted December 20, 2002 Author Share Posted December 20, 2002 ok why I need so much fuel, I am installing in my 280z a turbocoupe 2.3 turbo and cranking boost to about 30psi and myabe even some nitrous, will i need 100 psi not likely but running that kind of boost and maybe a little nitrous, I want to be damned sure I do not lean out Quote Link to comment Share on other sites More sharing options...
fl327 Posted December 20, 2002 Share Posted December 20, 2002 or two Quote Link to comment Share on other sites More sharing options...
Guest Zcarsmakemyheadhurt Posted December 21, 2002 Share Posted December 21, 2002 Sounds like you need a Aeromotive or a Weldon... Quote Link to comment Share on other sites More sharing options...
TimZ Posted December 22, 2002 Share Posted December 22, 2002 ok why I need so much fuel' date=' I am installing in my 280z a turbocoupe 2.3 turbo and cranking boost to about 30psi and myabe even some nitrous, will i need 100 psi not likely but running that kind of boost and maybe a little nitrous, I want to be damned sure I do not lean out [/quote'] I was guessing that you were running a rising rate FPR, which can easily drive your fuel pressures to 100psi or higher. I guess I don't know what special requirements a nitrous system puts on your fuel system, but I'm pretty sure that they don't require higher pressure than the injectors do. So, what you really need to be concerned with is whether the pump can supply enough fuel at the maximum pressure that you expect to run, which looks to be about 75psi. I believe that you were on this track with your oringinal question. There is nothing wrong with having headroom, but I'd concentrate on having headroom in flow capacity at 75psi, rather than being capable of 100psi (assuming that you are not using a RR FPR). This is what will keep you from going lean. Unfortunately, most manufacturers don't give these specs - their ratings for high pressure pumps are usually given at 43psi, and many of them drop like a stone as the pressure rises. Consequently, the '500hp' rating doesn't mean diddly when you are talking about a forced induction application. If you cannot find out what the pump will flow at 75psi, keep looking (or take your chances). Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted December 23, 2002 Share Posted December 23, 2002 I'm running a pair of Walbro pumps in tank on my Supra. At high pressure like 100PSI flow drops dramatically. If you hunt around you can find some sites that have flow tested these pumps at pressure. Walbro has a designation for pumps that cantake higher pressures to - HP is what I THINK it is. these cost a a bit over $100 - about $125 if memory serves. In my case they're actually not terribly noisy either. If you can run dual pumps consider this type of setup. P.S. Watch the amperage draw too. Stock supra pumps flow GREAT but a single one draws as much as TWO Walbros! Guys run these in pairs too but when you add up the draw of the pumps and accessories you don't have anything left! Higher pressure draw more power too BTW. Quote Link to comment Share on other sites More sharing options...
evildky Posted December 23, 2002 Author Share Posted December 23, 2002 not planning on needing a full 100psi just looking for one capable in that event of, with nitrous it pressurises the fpr on top of the boost condition to up the fuel flow to compensate for the additional air being introduced via the nitrous, I don't want a pump thats gonna quit when the pressure starts building, looks like the msd unit will meet my needs I think, it out flows the 190lph but falls a bit short of the 255, but at that price I am hoping it will do the trick, will be running full compliment of guages to monitor a/f ratio, will find out if it can handle it Quote Link to comment Share on other sites More sharing options...
TimZ Posted December 23, 2002 Share Posted December 23, 2002 I don't want a pump thats gonna quit when the pressure starts building' date=' looks like the msd unit will meet my needs I think, it out flows the 190lph but falls a bit short of the 255, [/quote'] Does it? Were you able to find flow specs on this pump for higer pressures? I didn't look for terribly long but all I could find was a regurgitation of MSD's sales blurb, which included nothing about it's performance at specific pressures. Care to share your findings/source? Quote Link to comment Share on other sites More sharing options...
evildky Posted December 24, 2002 Author Share Posted December 24, 2002 well acording to the msd web site their "msd high pressure electric fuel pump" is "Capable of 43 gph at 40 psi" and acouding to autoperformanceengineering the Walbro 190ltr/hr " 155 ltr/hr at 40 psi. " and the Walbro 255ltr/hr "These pumps flow 255 ltr/hr at 40 psi" and acording to a conversion website 43 gallons =162.8 liters so that makes it a bit larger than the 190 but still quite short of the 255 but I am only shooting for 300hp so I am thinking the msd pump at about half the cost should do the job, unfortunately msd does not list a peak pressure, but they tend to make a quality product and stand behind anything bearing their name Quote Link to comment Share on other sites More sharing options...
TimZ Posted December 27, 2002 Share Posted December 27, 2002 This was exactly my point. 40psi of fuel pressure is most likely what you will be running at zero psi of boost. The output flow of many pumps drop dramatically as pressures rise above this level. For 300hp, your flow requirements are considerably less than 155L/hr - more like 100L/hr. Problem is - MSD NEVER SAID ANYTHING about this pump's capabilities at 75psi. They don't have to stand behind it - they never claimed it would do that. If I had to guess, I would say that the MSD pump will 'probably' still flow 100L/hr at 75psi, but that opinion is worth exactly what you paid for it. Your best bet is to call MSD and ask a tech assistant specifically what the pump will do at 75psi. BTW, if the tech says it will 'probably' work - then he doesn't know either. They will either have the spec or they won't. Finally, I thought that you wanted nitrous in addition to this. I'm assuming that your 300hp goal did not include the nitrous. You still have to account for the extra fuel flow required by the nitrous. And, if you are planning on using a dry manifold setup (i.e. pinching off the regulator for added fuel flow), then you will need to be able to go to 100psi (possibly higher, depending on the amount of nitrous you are adding), and still meet your fuel flow requirements. I did some quick calculations, and assuming that your injectors were flowing 300hp worth of fuel at 75psi, you would need to jump to 100psi (minimum) at the injectors for a 50 shot, and 120psi (minimum) for a 75 shot of nitrous. This means that for a 75 shot, the pump would have to be capable of supplying 375hp worth (~115L/hr) of fuel at 120psi. In this case, my guess would be that the MSD pump will 'probably not' meet your needs, as many pumps just don't go that high at any flow. One more example, then I will shut up... Kinsler sells a pump which I'm pretty sure is the same pump as the big Aeromotive or Paxton pump. You know - the big, billet cylinder, monster looking thing that is rated for craploads of power (this one...) . According to Kinsler, this pump flows: At 0psi, 445L/hr (i.e. just squirting into a bucket). At 50psi, 291L/hr. At 70psi, 199L/hr At 100psi it's down to 95L/hr. At 120psi it is not rated, presumably because it does not flow anything at that pressure. This pump is most likely rated at 1000+hp (Summit says 1200hp), due to it's flow at 43.5psi (around 320L/hr or 519lb/hr, which correlates quite well with Summit's rating of 500lb/hr at 45psi). At 100psi, however, it's only good for about 300hp. To put a finer point on it, that pump would not meet your requirements, assuming you want to add dry manifold nitrous to your existing 300hp setup, even though it's rated for 1200hp. Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted December 28, 2002 Share Posted December 28, 2002 Tim is exactly right - this is why I'm running a PAIR of 255LPH HP pumps. On boost I'll see pressures as high as 80PSI! At that pressure my pumps are putting out a good bit less than 255LPH each BTW - I'd run a wet shot of nitrous or a standalone ECU that allows you to add injector pulse width instead of monkeying with fuel pressure. Screwing around like that is asking for trouble - no way would I do it that way. Rupture that FPR diaphragm and all hell breaks loose. fuel gushes through the vac line into the intake - filling it quickly... Quote Link to comment Share on other sites More sharing options...
TimZ Posted December 28, 2002 Share Posted December 28, 2002 Originally posted by BLKMGK:BTW - I'd run a wet shot of nitrous or a standalone ECU that allows you to add injector pulse width instead of monkeying with fuel pressure. I completely agree. Especially considering the added pressure requirements of forced induction, it's really a crapshoot as to whether the pump will supply any additional fuel, let alone enough to keep the mixture correct when you add the nitrous. For this reason, I was going to suggest going with a wet system as well. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted June 6, 2003 Share Posted June 6, 2003 Excactly how much Oxygen is in automotive nitrous anyways? Are there different grades? Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted June 6, 2003 Share Posted June 6, 2003 Excactly how much Oxygen is in automotive nitrous anyways? Are there different grades? Nitrous is N2O. There is one oxygen atom bound to a pair of nitrogen atoms. This will not change, no matter what grade. Old thread, eh? It's a good one though. BTW, the Bosch high pressure pumps will operate at good flows over 100 psi. Nothing else like them, although the CIS injected turbo Porsches ran two hp pumps plumbed in series. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted June 6, 2003 Share Posted June 6, 2003 Glad to see this post and others like it resurface. Tim's point earlier about the BIG! Aeromotive pump and the MSD pump is why I am disappointed (but not surprised) that manufacturers do not publish performance specifications like this: http://www.gnttype.org/techarea/fuelsystem/walbroflow.html The Walbro GSL392 is one that I and many others have used making a lot of HP with a lot of boost. With this type of information, knowledge of your FP @ 0psi, max boost psi and HP goal, you could then make intelligent decisions on a pump. Also never forget that pump performance, especially at high pressure, is greatly impacted by voltage, especially the lack of it. Do not get caught up in advertising hype. Quote Link to comment Share on other sites More sharing options...
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