In general, a stock SL6 fuel pump, in good working order, will keep-up with a 4 bbl carb and a SL6 engine up into the 5000 rpm range.
Here is another data point, I put small N2O systems on stock 1bbl engines and simply "T" into the stock fuel delivery system to feed the NOS... the factory pump keeps-up with that extra fuel demand. (50-75HP N2O system)
For bigger N2O systems, you should always run a seperate fuel sysyeem with an adjustable regulator.

Note that there is a lot more to a fuel system then the pump. The condition of the tank, pick-up tube, fuel line and fuel filter all have a impact on how much fuel the system will flow.

Most of the electric pumps I add are back by the fuel tank and push fuel up to a mechanical pump. The electric pump is switched so I use it to prime (fill) the carb. if the car has been sitting and I also turn the pump on when making a high rpm pass. I do not run the electric pump "full time"... the mechanical pump pulls fuel thru it when I am not using WOT.
DD

The picture of the fuel pump caught me eye. It looks like the "close to the block" pump (as opposed to the "two inches off the block" pump). What are the best mechanical pumps to buy for street use and how do you specify the one close to the block?

By the way those are great pictures of a sweet engine and a sweet car.

The pump used on the Guzzi engine is a standard pump you get at most auto parts stores these days. As already noted, the replacement pumps do a good job for all but the most wicked SL6 engines.
The next step is to get a high volume pump for a big block Mopar and swap-in the arm from a SL6 pump.
DD

Now ya got me thinking ,I should have done that,will be going to pick a part in the morning,if its not raining,tranny lines,termastat housing,starter are on my list,want small light starter,like 98 Dakota,what else has the starter i am looking for?Mark

doug i have tried swapping the slant fuel pump arm on a bb fuel pump it worked but what is your method of rolling back the staked housing that holds the pin in place,i used a sharp chisel to widen the slot until i could pry the pin loose.

Doug,

Does it have to be a big block pump or could a small block pump be used? I have a Mopar Performance 6 valve race small block pump that I would like to be able to use on something. The fuel pump won't clear a small block passenger's side inlet water pump so I had to switch to a Carter pump.

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Joshua

I have always used the BB pumps but my guess is that the SB pump can also be made to work.

As for the staked-in pin, I use a small drill to open-up the area so the pin will come-out. Epoxy holds it in upon reinstall.
DD

doug what pump do you order ,is it a stock bb replacement pump or is it a street and strip pump like the carter mech pumps in the summit catalog

doug you say in the new tread to cut the fixture bumps off the block are you referring to the square bump at the deck surface and what is the reason for cutting them off

This one flows 120 gph at 5 to 7 psi.



This one flows 120 gph but at a higher pressure

Yes, those are just extra weight and they sometimes get in the way of the exhaust manifolds or header flanges.
DD

Speaking of headers, the modification work to the front header has been completed and we now have over an inch of clearance between the steering box and the collector.

The bad news, one torn "Anchor brand" motor mount during the process.
DD

Hey Doc, You said you just tee into the fuel system. Where do you tee into? Fuel line or ? I'm not totally familiar with N2O.
Thanks,
Wylde Bill

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63 Dodge 330
00 Sportster Rigid Bobber
05 Dodge Stratus (Wifes)

I put a brass "T" fitting right at the fuel pump, the high pressure side has a 1/4 NPT thread so the fitting is pretty common.
DD

Turns out the big 6 valve small block race fuel pump I have isn't like the smaller high performance Carter pumps so the slant 6 pump arm doesn't fit.

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Joshua