Saddle Tanks and Fuel Injection

[todd99]

So I am thinking about switching from carb to EZ EFI and have a question for the board. When converting to fuel injection I will have to convert to an electric fuel pump as well. Most electric fuel pumps are required to be mounted near the tank, which will be a problem with dual tanks.

So my questions for you are:

Do any of you know of a fuel pump that can be mounted after the tank selector, several feet from the fuel tank?

Will I have to convert to one saddle tank?

What is the capacity of a saddle tank?

[todd99]

...

[CSmith]

Maybe use a high volume mechanical pump to feed an electric pump?

[mrein3]

Interesting. Surly somebody must have EFI and one or two saddle tanks.
TTT

[Crabass]

My '87 Silverado w/efi has dual saddle tanks with pump in each tank and a selector switch on the dash. IIRC the aftermarket efi vendors have kits that have to be purchased separately to accommodate dual tank setups. Contact the seller you intend to purchase from.

[todd99]

Originally Posted by Crabass

My '87 Silverado w/efi has dual saddle tanks with pumo in each tank and a selector switch on the dash. IIRC the aftermarket efi vendors have kits that have to be purchased separately to accommodate dual tank setups. Contact the seller you intend to purchase from.

I will email FAST and see what they have to say.

[mrein3]

Originally Posted by todd99

So I am thinking about switching from carb to EZ EFI and have a question for the board. When converting to fuel injection I will have to convert to an electric fuel pump as well. Most electric fuel pumps are required to be mounted near the tank, which will be a problem with dual tanks.

So my questions for you are:

Do any of you know of a fuel pump that can be mounted after the tank selector, several feet from the fuel tank?

Will I have to convert to one saddle tank?

What is the capacity of a saddle tank?

While sitting in an overly exciting work meeting I got to thinking about this thread. I remembered recently that there was a thread about multiple fuel tank selector valves. I did some digging through my subscriptions and found what I was looking for.
http://67-72chevytrucks.com/vboard/s...d.php?t=453477
Slide down to lucky post #13 and click on the anderson link. I'm guessing that the valve pictured on the right on the page in that link might get you the plumbing you need for fuel injection in a saddle tank truck.

It would be a lot of plumbing but I'm guessing that those ports above each other are open when they are pointed at. In other words you could have your to and from to all 2 or 3 tanks running through this. Have your pump right after this valve. Use gravity to get fuel to the valve. Put a return back to the tank selected.


To answer your questions directly...
You might have to forget about the RHS saddle if you have to saddles.
The seat tank and LHS saddle tank are probably close enough to the selector if it is mounted to the left of the driver's seat like I've observed on every selector I've see.
My saddle tank holds 17 gallons.

[todd99]

Thanks. I may just go with the LHS tank and buy a jerry can if I do make the conversion. I did email FAST and I will post up what they have to say when they reply.

[Ed 72 Sierra Grande]

Originally Posted by todd99

Thanks. I may just go with the LHS tank and buy a jerry can if I do make the conversion. I did email FAST and I will post up what they have to say when they reply.

Do you have a 3 port or 6 port selector valve? my 72 gas tank selector is the 6 port version which has vapor/vent/return lines.

You could eliminate the in the cab tank and use the selector valve to run 2 saddles instead of the in the cab and Driver side saddle.


Proper PSI Fuel pump Place it after the selector valve. If you have return lines you may have to get a fancy fuel regulator of the return style type.$$

So long as you have the rt pump and psi your efi should work.

[todd99]

I have a 3 port selector valve. So if I understand you correctly I could get a 6 port valve and it would select the return line as well as the main line? Could you post up a link or picture of the 6 port valve?

[Ed 72 Sierra Grande]

Originally Posted by todd99

I have a 3 port selector valve. So if I understand you correctly I could get a 6 port valve and it would select the return line as well as the main line? Could you post up a link or picture of the 6 port valve?

Will snap pic tonight and post. Those 6 port valves are pretty spendy. Around $150-$180. Anderson

JUst use the valve you hve to use any 2 tanks. Since you don't have return lines, just spend the money on a nice regulator to ensure proper psi regardless of which tank you select.

In some cases people cancel out the return lines without any issues, so why spend $ to add them if you didn't have them. You wouldn't need the return style regulator either, just a regular one and fuel pressure guage for exact psi.

All this depends on your efi set up requirements of course. But otherwise you should be able to work around the brass valve.

Hope this is helpful

[todd99]

Thanks, very helpfull. So you don't need to have a return line if pressure is accuratley regulated? Seems like the excess pressure would damage the pump. I hope your right it would certainly make my life alot easier.

[BIGKEV]

Last year I did a 94 tbi 350/4l80e into a 73 c10. I put saddle tanks from a 8? chevy 1 tank with an in tank tbi pump, and a cheap amateur zone inline on the other and wired a relay and a toggle when the tank with the in tank pump got low you hit the switch and it simply transfers the fuel in a couple minutes.

[todd99]

^Thats a really cool idea.

I would like to know if anyone can validate that with quality pressure regulator that I wouldn't need a return line.

[BIGKEV]

Originally Posted by todd99

^Thats a really cool idea.

I would like to know if anyone can validate that with quality pressure regulator that I wouldn't need a return line.

I always like to run a return line, never any vapor lock issues.

[todd99]

vapor lock eh, good to know.

[BIGKEV]

Just noticed, we're both from Prescott. Small world!

[todd99]

Wow! Small world indeed. What do you drive, maybe I've seen you around.

[BIGKEV]

I have a 71 C10 lwb, it's white over blue, I used to have a flat black 93 S10 with small block on C6 vette wheels.

[jst4fun]

question for you guy's. What size tanks and where do i get them from for the saddle tanks for a 72 c10 swb. I'm putting a 572 tt motor in and need one tank for pump gas and the other for race gas so trying to figure out a saddle system for both sides would greatly help me out here. Thanks for any help.

[Gromit]

Capacity on my saddle tanks is 18 Gallons each, plus or minus about 1/2 gallon each.

I found this out by filling up each tank with a hot water / Tri-Sodium Phosphate mix - one gallon jug at a time when I was cleaning mine... and making a hash mark for every trip back to the hot water sink.. (meanwhile, all my friends were out having fun)..

My tanks came from Colorado Leisure Products - (I think a now defunct company)..

You may also consider computing the volume by measuring your tanks' dimensions

Photo attached is not so great but you might be able to at least see if they are similar to yours