Mikuni 44phh Fuel Pump Type?

[fugetaboti]

I have a 73 240z which I'm assuming should have an electric fuel pump already, but I think the previous owner removed it. I'm trying to figure out what kind of pump I should by to run these carbs, and what fuel pressure regulator? Any help would be greatly appreciated.

Thanks,

Rick

[240ZGL]

I have been looking into this becuse I'm going with a set of 40's. The pump I'm looking for is 3 1/2 to 4 lbs, non-pulse type hi flow, about 50 to 70 gph. It will not need a reg which usually works by cutting down on the flow. Dellortos work best at 3 1/2 lbs of pressure.

[240ZGL]

The one thing I'm looking into is the distributor. What will be the best set up to run since there is no vacume port to work the vacume advance.

[Carl Beck]

What engine are you talking about? What cam, what head work etc etc..

Carl B.

[fugetaboti]

Carl, I have an L28 N42. At the moment, I do not have a cam, but I'm looking into one. The only thing I need to know at the moment is whether anyone knows of a specific fuel pump and regulator which works well for running these carbs.

Rick

[ZIII]

I have been looking into this becuse I'm going with a set of 40's. The pump I'm looking for is 3 1/2 to 4 lbs, non-pulse type hi flow, about 50 to 70 gph. It will not need a reg which usually works by cutting down on the flow. Dellortos work best at 3 1/2 lbs of pressure.

When you say set... do you mean two or triple-carbs? If you are using trip-carbs, may I suggest you consider the Holly Red.... I have one on my triple system, pressure is set at 3.5.... and the flow (which in this case is vitally important) is about 97gph.....

[Carl Beck]

Hi Rick:

Sorry - I should have addressed that question about the engine to 240GL...

At any rate - I can't give you a specific Brand/Part Number - because I haven't bought a fuel pump and regulator for a triple carb set up for about 30 years now... I am still running the Conelec Fuel Pump I bought back in the 70's... it's never failed... It puts out 7 pounds of pressure and 70GPH - and I have it regulated down to 3 lbs. with a Carter Fuel Pressure Regulator. The Conelec pump was an Aircraft Certified unit and at the time it was known as being one of the most simply built (fewest moving parts) and reliable pumps on the market. What's "best" today - I don't know.... but you'll need about the same spec.'s ( I think that AC actually wound up buying Conelec's patents).

Hi 240GL:

With the triple carb set up you need a lot of initial timing advance... about 20 degrees. But, you have to modify your mechanical advance so it doesn't start to come on until about 1800 RPM. Total advance seems to work best when limited to 34 degrees and you want that all in by 3500 RPM. Any good automotive electrical shop should be able to set your distributor up and measure/adjust the timing curve on a Sun Distributor Machine...(as long as you know what you want)

BTW - for the engine set up you are running - with triple carb.s .. you don't want a primary venture size much larger than 30mm. (most of these set-up's seem to come with 32's or larger.. and they bog badly off the line).

I've had Weber 40 DCOE's since the mid 70's - and really never did learn to tune them. But the guy that did finally set them up right for me - certainly knew his stuff... (thus my advice above)...

FWIW,

Carl B.

[fugetaboti]

Carl,

Thank you so much for your reply. I guess I'll just have to look for a pump which produces at least 3.0 PSI and 97GPH. The question now is where should I buy such a pump. Would Auto Zone or NAPA work?

Thanks,

Rick

[Carl Beck]

Hi Rick:

Just in my personal experience - in general NAPA has both better Counter People, and they offer better quality parts - if you ask for them, or let the counter person know you want them, and rare willing to pay for the higher quality parts that they sell. Usually the NAPA people will have access to the specifications of the parts they sell, and they are usually willing to look them up if your standing there in the store in front of them trying to make a decision.

In the last couple of decades... "price" seems to be everything.. indeed the only thing .. for most buyers and NAPA has had to respond to the price competition from the larger chain AutoParts Stores... so in many cases if you don't specify that you are looking for and willing to buy "quality".. the Counter People will grab the lowest price item to quote... In which case you might as well go to AutoZone or PepBoys etc.

In many cases the price competition has been great for consumers - in just as many cases it's really been a screw job... as always "buyer beware"...

good luck,

Carl B.

[240ZMan]

I'll throw a few thoughts in on this:

- I had a Holley Blue, but it was terribly loud. Is the Red loud too?

- I am now using a generic rotary from Autozone and mounted it using thick rubber straps usually used to mount mufflers. You really can't hear it in the car at idle.

- The easiest way to deal with lack of vacuum advance is switch to a ZX distributor. I have an 80 although I've heard some say the 82 & 83 curves are a little better. I tune my advance to a max of 35 degrees. This results in about 18 degrees at idle with my distributor. Driveability is great. You can usually get one at the JY for about $20. Make sure you get the aluminum piece that goes between the distributor and block as it's different for the later ones.

- I am running triple webers with 32 mm chokes. I have an N42 head, L28 flat top pistons, and 284/284 .480" cam. I live at 6000 feet and have no problem with low rpm bogging, although there is a lot more power above 3k rpm. Most people run with their main jets way too big. I am running 110 mains and might even be able to get away with 105 (if I had a set to try). Given my altitude, I'm going to run a little smaller than those at sea level, but when I first bought the carbs there were 140 mains and the engine wouldn't run except at idle and WOT ! If you're running with an L24, then I agree with Carl and wouldn't go larger than 30 mm chokes unless you go with a huge cam.

[240ZGL]

Found this, might be usefull. I know what I'm going to do for a fuel http://www.racetep.com/webfuelspark.html#webfaq

[fugetaboti]

Where do I find the jet sizes that are in my carbs? The only thing I've seen is something marked "OA".