wmf62

i am considering the options for a fuel pump and return line if/when i add EFI.

one option is to use an external pump and build a fuel return line diptube into the tank's level gauge flange.

BUT i've been told that an external electric pump might be VERY noisy... so i've thought about the possibility of a new tank with a built-in pump and return line. BUT this seems to be a VERY expensive alternative (Rock Valley's SS tank/pump is approx $1100).

does anyone know of other sources for new tanks with in-tank pump/return line? OR, does anyone have any other suggestions?
Bill

mredi1

Rock Valley did a stock tank for my 65 which reduced the price by about $400. I needed a new tank anyway. If your tank is goood they may be able to modify it as well, to save some money. Just a thought.

Ironcross

There may be a way, The 1976 Eldorado with Electronic fuel injection uses a external high pressure pump. As I recall the pressure is in the neighborhood of 90 Lbs. I would think that has enough pump pressure.

Tyler Townsley

http://www.racepumps.com/applications.html

No return line needed and pretty straight forward.

Tyler

Sean Dunshee

Is a return line needed if doing a TPI engine? What about a GM Ram Jet?

wmf62

Tyler
neat, but will it fit in the space between the frame and the block in a C1?
Bill

firstgear

the new Corvettes (C5 for sure) use a pump that has a short return line. It really becomes where do you want to put the regulator and be able to adjust it.

Again, Bill, if you look at the Kinsler site and down load their catalog there is a bunch of info in there along with sketches of fuel line layouts.

I bought the Rock Valley set up. If I was to do it again, I would ask them to make the tank about 1/4" smaller in all dimensions. It fit, but oh is it tight! I am guessing that there is enough body variances that what ever they used to set up their baseline it was at one end of the size and my car was at the other end. The fit was tight!

Herb

wmf62

Herb
sorry, i was distracted by the picture on their website and didn't look any further...
bill

firstgear

I understand, I had to get bi-focals after starring too long....

Tyler Townsley

Yes. It is actually smaller than the stock pump.

Tyler

Tyler Townsley

According to the wriiteup the regulator is the key. It controls the pressure without needing a return line. I am in the process of putting an old hilbon modified for efi on a bb and a sb using this pump setup and this: http://www.megamanual.com/v22manual/mintro.htm controller.

Tyler

62fever

Read a magazine write up on this pump and for EFI you will need some type of check valve in line between pump and injectors to keep the pressure up for starting. If not, it takes quite a bit of cranking to get motor going.

wmf62

Tyler
the racepump is intriguing... the part that is giving me the biggest nightmare (in my mind...) is the gas supply/return line connections in the fuel loop and the directions to run the hard lines to & from the fuel loop to the gas tank. i keep thinking that it could end up looking real 'Bubba'....; and the whole purpose of this is to try to retain the 'look' of the old rochester FI as much as possible.

i mentioned the racepump to my shop guy and he said he is familiar with it through the literature but has never used one, he is not sure in his mind that there is NO pulsation (caused by the piston nature of the pump) in the fuel flow. he says that pressure pulses in EFI nozzles/fuel loops is not a good thing. he said it might be worthwhile trying on something that he is building in his shop where he can put hands on when it's running, but he's leery of me having to deal with it alone.....

i didn't see a price, do you know what it costs?
Bill

1960Vette

I stopped at the racepumps booth at SEMA and he recommeded using a return line from their regulator on an EFI application to help cool the fuel. My '60 tank has a vent line fitting on the top of the tank which I would assume could be used for a return line, but do not know about the '62 tank. I like the concept of using a mechanical pump that can obtain the higher presssures required for the EFI without modifying the tank for an internal pump. Do not have first hand experience with the "noise" problem associated with external pumps, but late '80's Ford PU's have external pumps and are readily available and I do not recall any noise issues. There are many other external pumps available for usage on EFI applications.

This is a great project and many of us will be anxiously watching your progress.

Plasticman

I would not use the existing vent line as a return.

You would still need a separate vent. A vent provides the displacement of air with "used" gas, so without a vent, the tank would try to collapse and eventually would not provide any fuel (or use a vented cap, which is problematic unto itself). And the return of heated fuel from the engine compartment would increase the vent's flow.

And besides, the existing vent line is probably too small.

Plasticman

firstgear

Bill, if you are not making a full out race car (which I don't think you are), if you run the regulator and return line somewhere near the tank with a single line out to the injectors, you will be fine.

The reason for running a reciurculating line through the regulator and then taking the excess back to the tank is that the regulators need a flow of gas through them in order to regulate properly.

Because there are pressure losses in each length of tubing past the regulator if you want to have the absolute best and precise pressure regulation, by having the regulator as close to the motor as possible enables this to happen. But only really required if you are going flat out all the time.

In my discussions with Bob Ream at www.imagineinjection.com we discussed this at length and for normal street driving if is just fine. This is how the newer Corvettes bring the fuel to the front of the car with a single gas line. The fuel regulator is very close to the tank and the fuel recirculates through the regulator with that single fuel line to the fron of the car.

firstgear

my Rock Valley tank....





don't forget your inline fuel filter, with the orifice openings in the injectors you need this filter between the regulator and the tank


my regulator


my Accel Gen 7 controller


wire harnesses and base maps on disk, all of the plugs on the harnes were plug and play


return line not yet installed in this photo..


Probably won't be until next weekend when I get a chance to put the car up on a lift again, but I will get some more photos.

Herb

wmf62

i have just done an extensive google search on racepumps and found that a LOT of folks are having vapor lock problems with the pump....

http://www.camaros.net/forums/showth...light=racepump

http://www.camaros.net/forums/showth...ight=fuel+pump

http://www.nastyz28.com/forum/showthread.php?t=76078

http://www.pro-touring.com/forum/showthread.php?t=18029

http://www.camaros.net/forums/archiv.../t-116445.html


plus, i don't see how a built-in regulator is going to be as sensitive/responsive to engine load/fuel requirements as a vacuum controlled pressure regulator that is at the end of the fuel loop....

but...

http://www.pedistributors.com/news.p..._from=&ucat=5&


Bill

Stan's Customs

Looks like heat sink the pump while in heavy traffic is the first issue. Priming the system with cranking speed (starter) only, shoud it leak down, being the second issue.

I'm sure a small grill fan with a vent directed at the pump would help . And an electric pump for priming the system (as one of the other forum memembers suggested), allbeit noisy. Guess it cold be used as a "limp in" back up too. Might not be such a bad idea....as a backup if you are 500 miles from home.

Used electric pumps are cheap and a good option, especially if only used only occasionally, or never.
Now...making it look decent might be an issue..

THEN there "is" the possibility that these guys are having other problems ...like BUBBA issues that are the REAL problem...and the pump works GREAT as is.

Maybe something as simple as a heat shield between the header and the pump would fix the heat sink issue...(plus you have the advantage of cast iron manifolds..which is some cooler.)

Looks like a tight system that doesn't leak down would fix the priming issue....and I'm I'm sure your system would be tight. However, on the rare occasion that an injector or something might leak down...a can of starting fluid would get you back to the shop...or repair facility when out of town.

Providing cranking speed wouldn't prime the system after a few seconds of cranking.....I don't know whether that has been "really"established or not.

Hope these turn out to be simple issues...so poor folks like me can have EFI too..HA!

Best regards...Stan

Ironcross

Use two pumps, one in a tank to push to a HP pump on the frame to the engine. It shouldn`t be too much of a job making an aluminum tank with a pump inside and sufficient return connections.