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wet77
04-22-2004, 05:47 PM
I am building a new motor for my eliminator and am going to use an electric fuel pump, I have used the Holley (blue) pumps before with the pressure reg.
My ? is if I plan to run nitrous in the future on this new motor which pump would be a safe bet to go with?
I do not need the most expensive top of the line just a good reliable electric pump.:D
Thanks guys

Rexone
04-22-2004, 05:53 PM
My preference is Mallory for the money. I'll never use another Holley, too many failures.

Squirtcha?
04-22-2004, 05:57 PM
Amen Rex. Leakin so and so's too. I've got two of em and they both leak from the plate. One of em did it since the day I took it out of the box. Fortuantely I only use it for nitrous so it only runs for 15 seconds at a time, the motor's on a mechanical pump.
Oh yeah, I use the other electric as an oil change pump. It works pretty good for that and even if it does crap out, I'll be in my garage and not in the middle of the lake.

Beautiful Noise
04-22-2004, 08:58 PM
I only run the Holley Blue electric Pump and i've had it on the boat for 28 years, I've replaced the cap once and the bottom once and it still works great:D

HotRod Sprint
04-22-2004, 09:12 PM
Originally posted by Beautiful Noise
I only run the Holley Blue electric Pump and i've had it on the boat for 28 years, I've replaced the cap once and the bottom once and it still works great:D
Damn Steve, where you been hidin, haven't seen you on in a while. Oh ya, I'll be running a holley blue with my Gen V.
Rod

moneysucker
04-22-2004, 10:25 PM
I am glad to hear the firm Aeromotive! I just ordered one for the new motor. The old holley will go in the other boat or as an oil change pump. I like that idea I always used a drill pump.
Cy

Cs19
04-22-2004, 10:27 PM
Product Engineering Fuel pumps.
http://productengr.com/images/Product%20photos/Fuel%20pumps/PE%204500%20web%20a.jpg
After youve bought two holleys or whatever Jeg's has on special, you could have bought one of these and not had any down time.
Also has a 2 year parts and labor warranty.

quiet riot
04-23-2004, 03:58 AM
My ? is if I plan to run nitrous in the future on this new motor which pump would be a safe bet to go with?
How much n2o are you planning on using? How much fuel will the motor require?
If you are planning on using more than a 150 shot of n2o you should go with a seperate fuel pump for the n2o system to keep the pressure right for the motor when not running n2o and also have the right pressure for the n2o side when its activated. You could use a good fuel pump and dual outlet regulator and have a return line to the tank if you don't want to run 2 fuel pumps, but then you're talking some $$ for the good pump and good regulator also.
If you don't plan to run a lot of n2o just find a pump that will feed the hp requirements of the motor + the n2o system and about a 50-100 hp flow of fuel safety margin.
I run a second fuel system for my n2o (250hp shot.) I have an 8 gallon tank that I put high octane gas in for the n2o system. I use a carter marine fuel pump that is followed by a pressure cut-out switch for the n2o fuel delivery. The carter fuel pump will draw fuel up to a 15 ft height so it can be mounted anywhere (unlike holley and many others that have to be mounted below the fuel level and close to the tank because they don't pull well.) The stock carter marine pump (omc, volvo, and several others used this carter pump) will feed 400hp worth of fuel at 6 psi so it will cover most n2o hp levels and doesn't need a regulator. I turn the carter pump on with a relay that is on the n2o arming circuit so it only runs when the n2o system is armed.
The 2 fuel systems is really nice if you want to run much n2o. In addition to the above mentioned, you can fill your regular gas tank up with the lowest octane that the motor requires. Then you put good gas in the n2o fuel system tank. If you run the n2o system at a low hp level (150 hp n2o boost) then the mix of the gas will keep the octane right. When I jet the n2o system for more power then I switch the motor's fuel pump over to good gas also and then I have the octane required for higher n2o boost. This way I don't have to mix gas or put expensive gas in the main fuel tank that gets used 99% of the time when not using the n2o.
This has worked for me for many years on mild engines running a lot of n2o and I have never had a problem with it. N2o can be very reliable when used this way (add a timing retard if ya run high hp n2o also.) It also makes for very consistant hp regardless of air conditions because you have your own O2 in the bottle.
Just some food for thought on fuel delivery.
jd

wet77
04-23-2004, 05:43 AM
The motor I plan to build should be around 500hp and the nos will be no more than 150hp boost
I was looking at the mallory pumps that rex mentioned thats about the price range I would like to stay in.
with that type of HP and a 850 double pumper what type of pressure should I start at?:confused:

Rexone
04-23-2004, 10:18 AM
Pressure should be kept to around 7psi to avoid forcing the needle off it's seat and flooding over. Some carbs will hold slightly more but 7 is very adequate as long as you have good pump and plumbing flow. You may see fuel pressure drop a pound or two at full throttle. That's pretty normal.

skeepwerkzaz
04-23-2004, 10:35 AM
I would get the electric kind that bolts to the pad on your motor and runs off of your camshaft. Oh wait I guess that is a mechanical one. :D But seriously get a good mechanical one, with a bypass-style regulator and never think about it again. Just look around at some seriously big H.P. stuff and notice that the lions share of them all run mechanical.;) I have a six-diaphragm 130 GPH mechanical that was about $130 new, and can pump WAY more fuel that any other electrical I have run. (holley red, blue, carter, mallory...) Mechanicals have much more power available to run them, and therefore can achieve higher operating psi without suffering flow. (think about the dinky electric motors used to drive a fuel pump!) Most electric flow #'s, (save the $400-500 dollar range) are rated at zero pressure. Add a few lbs. to that and the actual flow drops way below what you think you are getting. Any decent electric should suffice for the N2O, if you are planning on running a separate fuel system, but I would imagine that with a good mechanical, and only a 150 shot, I wouldn't think that would be necessary. Although I have always been intrigued by using something like alcohol as an enrichment fuel:cool:
My .02,
Skeep
P.S. "That type of H.P" was being made in the late sixties from the factory. They used 3/8 fuel line, and factory fuel pumps! :confused:

Speedin' Ian
04-23-2004, 10:48 AM
I was kind of wondering which pumps are the best also. I have a blown 468 runing 11-13lbs of boost with two 850's and I would hate to lean it out. Currently I have a Holley black running to a distribution block which splits it to two regulators. From there I have have four lines, one running to each bowl. I thought this would be more than adequate, but have had people tell me it is not. I just installed a fuel presure guage, the only problem is I could ony install it before the regulators, so it reads the actual pump pressure, which is between 12 and 15lbs. I figured if it dips below 6 or 7 lbs on a pass I'll know that I don't have enough preseure. What do you guys think? Oh yeah the pump is force fed by a t-tank.
Sorry for hi-jacking your thread wet77, but I was wondering about the same thing.

Rexone
04-23-2004, 11:08 AM
Mallory or Aeromotive Electrics or the 6 valve mechanicals are all good choices as well as the other one pictured above I'm sure. I'd run any without thinking twice. The Holley is more of a design problem in my mind than a supply one. They don't tolerate any moisture and as soon as any corrosion occurs on the steel vanes they lock up and your volume goes down and also it wipes out the seal and they leak. They're a pain in the ass from that perspective.
But the pump is only a piece of the puzzle. The fuel system must be of adequate design. Good flow, proper regulators, etc , etc. The flow through the blue Holley regulators is pathetic, (look inside one). People get by with them but frankly I don't know why in some applications.
You can get by with a good high flow deadhead regulator (Mallory or Aeromotive) but the preferred method in my mind is a bypass regulator after the carbs and Info and others have promoted here on ***boat. You not only get full fuel volume to the carbs as needed, you get the added cooling effect of returning used fuel back to the tank.
There's lots of threads on ***boat regarding fuel pumps. Do a search and use the resource.

Bense468
04-23-2004, 11:17 AM
Mike is right the bypass after the carbs is the way to go. Feed the carbs with what they need/want and bypass the rest. Very nice setup this way, if done right.

quiet riot
04-23-2004, 08:58 PM
If you're gonna play "ricky-racer" you are always running good gas, aren't you?
If you use more than 150 hp of the n2o then the increased octane (required for the additional cylinder pressure with lotsa n2o) actually starts being detrimental to performance when not using the n2o. Higher octane gasoline doesn't burn as efficiently/easily as regular gas for lower cylinder pressures (normal compression, low boost, or no extra charge of n2o and gas.) Not to mention that tuning (carb jetting requirements, timing, spark plug heat range) change with different fuels' burining characteristics at the low cylinder pressure. My 10:1 sbf ran 2 mph faster and kept the plugs and exhaust cleaner on the 91 oct pump gas than on 110. I need the 110 oct when running the n2o at 250 hp setting though.
As said earlier, with the small shot of n2o he's planning on using, any decent electric or mechanical pump with enough flow rating at 6psi for the motor and n2o system will work fine. There have been several examples of what people have had good luck with stated above.
A good pump, regulator and return line would be best for keeping steady pressure with the instant bump of the n2o fuel kicking on, that way there isn't the momentary lean out that occurs when the regulator drops and recovers for the fuel of the n2o system. Its not like a carb that has a couple of bowls of gas sitting there ready for full throttle to suck on them and 6psi of pressure to backfill the bowls before they run dry. Its like a fuel injection system that needs the fuel to be pressurized at the point of entry (injector nozzle) all the time to run correctly. Thats why even most of your 4 cyl efi cars have a return line and keep a constant minimum fuel pressure supplied.
If a motor with n2o runs lean enough (say the regulator sticks for a couple of seconds, fuel delivery is blocked, etc) its can burn the best forged pistons in just a couple seconds. This is why I'd recommend the fuel pressure cut-out switch ($25) be wired on the n2o fuel side of any n2o system to shut the n2o off if the fuel isn't there for it to burn with, so it doesn't find another source of burnable material, like the pistons.
boy, I sure ramble a lot sometimes.
jd

wet77
04-24-2004, 06:41 AM
I like that idea about the shutoff switch, now I have a daytona eliminator this is going in and it has the tanks on both sides.
Anyone have this setup and have ideas on how the plumbing would look on this:confused:
Example: Fuel tanks to a T then to filter then to electric pump.........:confused: :confused:
Considering the return line I see I have on the opposite end of each tank I have a fitting that looks like it could be opened for a return line attachment, would I have to return fuel to both sides:confused: To make them equal in amount of fuel?
Thanks for all the great help:D