All right, here's the big spoon

https://www.evolutionm.net/forums/sh...ight=fuel+pump
https://www.evolutionm.net/forums/sh...ight=fuel+pump


Read them both and you'll know exactly what a Walbro will flow, what HP it will support at what PSI, and the double pump options available from Buschur. Full Blown has a CNC version of the double pump that replaces the stock sender as a little more costly option.

 

But does that answer my damn question about my fuel problem? NO...Im looking for opinions on my fuel problem, so maybe I can find out what is causing it.

 

Depends what type of power your looking to get out.

 

Go to your local GM dealer. GM used a NVH 'sock' for fuel pumps on several cars in the 80'-90's. If you need an exact application 1987 Pontiac Fiero GT 2.8v6. I use these 'socks' on all Walbro pumps to quiet them down.

 

Took my pump out, couldnt find anything out of the ordinary.....

 

With our setup you can run a denso and a walbro together. Just have the walbro come on at a certain psi if you are making enough power to need it. Otherwise you can use a single Denso and plug the other port, or you could run 2 Denso I guess you can do what ever you want haha.

 

Assuming the pump is working properly, you're simply running out of fuel at higher boost pressures. Your fuel system must have the capability to supply adequate VOLUME at the boost pressure that you're using to make power. In other words, if your base fuel pressure is 43PSI, and you boost 30PSI in the intake manifold, the injector needs to have 43+30PSI = 73PSI of pressure to "stay even" and deliver the same fuel volume out the end of the injector (since the manifold pressure is resisting the fuel spray). You need a pump that will flow the volume of fuel you need at the boost pressure you're going to use to make that power. Fuel pumps FLOW LESS as the pressure demands go up. At very high pressures, they eventually flow almost -0-. So you have to pick your pump or pumps to provide the proper volume that your HP will require.

If your engine needs more fuel than your system can supply, you run LEAN. Your engine control computer DOES NOT KNOW if your fuel pressure is dropping. It ASSUMES that your system is providing the proper pressure of fuel, and times the injector duty cycle accordingly. Even when you change the map, it does not take into account that your system is providing LESS FUEL than the computer uses for its computation, because the fuel volume at higher pressure can't keep up.

Buschur had exactly the same problem. When he went to the double pump, he picked up 50HP with no other changes except fixing his A/F tables to get his A/F back to where he wanted it after he went pig rich with the new fuel supply.

Please read the Buschur thread I left you above. It will explain exactly what is going on and the options you can use to maintain adequate fuel supply above 500HP.

 

Its not my pump cant flow enough fuel, its my pump may be failing on me due to its worked for the past month and decided to run lean the last 2 days up top which lets me beleive my pump may be failing or my Fuel pressure regulator has a problem.


-Full Blown- I really like your setup and you may be hearing from me soon

 

That's why I said "assuming your pump is working properly".... even with a fully functioning Walbro 255, though, if you've got the supporting mods for a 37R and are making over 500HP, you're going to run out of fuel, just like Buschur and a number of others have. That's why you'll need a dual pump setup of one kind or another. Full Blown has the added option of using Denso Supra TT pumps, which have a better reputation for reliability than the Walbros.

 

Ok, to clear it up, talked to John "Jestr" and he mentioned it being the line on the fuel pressure regulator...sure enough the line to the fuel pressure regulator was un hooked. Thanks for the help.

 

Are you running a fuel pressure gauge? I'll bet you aren't because if you had been, then you would have diagnosed the manifold pressure line being off, all by yourself. A fuel pressure gauge would also help you to diagnose if your pump ever should happen to fail, or is starting to go bad, and to know if it is delivering enough fuel up top under high boost conditions.

FWIW, I agree with CO V4, that you don't have enough pump for that turbo. No way. At least you should hotwire it with 12 Ga. wire, or even better go to the HO Buschur single pump. I realize that opinions are worth sh*t, but if it was my car with a 37R I would run the Buschur staged double pumper and a set of 1000 c.c. injectors.

With the bigger injectors you can run lower fuel pressures. Hey you have a huge turbo so why run the same pump I'm using with my stock turbo? I wouldn't trust the WALBRO 340 @ anything over 450 flywheel horsepower. Just my two cents.

 

I have SEVERAL friends with 500whp+ evos with same fuel pump I use..... I dont need those gauges, I have a wideband telling me its not getting enough fuel....I mean hell it cant be but a few things.... Fuel pump,FPR, Injectors+Fuel rail....And I bet if I had a "super-duper multi-fuctioning gauge that reads everything possible on your car including your temp of your *** on the seat, I would have know also. Right?

Just my two cents....

Money doesnt grow on trees, I just installed this turbo a month ago.

 

Hey you have a huge turbo so why run the same pump I'm using with my stock turbo?





Ask the 200+ People with the same setup as me.....

 

Why is it necessary to insult someone without actually insulting someone just to save face on this forum and not get a moderator on you ***... Some reason u ppl believe that money comes hand over fist. The turbo kit was a stretch for him to get ahold of and has had minimal problems @ this point. The fuel pressure regulator was a freak thing that with out past experience with this issue who would have known? You keep screaming more parts more parts more parts like someone can bust there entire savings on it. The car runs excellent as is and has had this one issue. It has had no fuel starvation issue's until now and im sure wont have any more in the future knowing the cause... Anyway i think some people need to think back and recall that this is a hobby and maybe people should be a little more understanding when coming to a public forum asking for help..... I mean isnt that what this place is for to voice concerns and ask questions???

 

Whatever. It's good that Evocrazy found the problem. Hope he put a fastener on that FPR hose. We're all happy he found it without anything expensive happening because he was running lean.

However, simply stated, if you're actually using the air flow potential of a 37R, you'll have to need to improve your fuel system to keep up, including your pump and injectors, or you will run lean. That's what many of the comments here were stating, with more explanation.

You can lead a horse to water...but some horses will still kick at you and blame you for having to walk there.... That's why most people who experience those horses are not very interested in walking them anywhere a second time...