Metalhead140

I think it's a completely different tank on the earlier cars. My issue with using the '82 pickup is that there's no baffling or surge control so it is likely (and people have reported) to have issues with starvation below ~1/3-1/4 tank.

diehrd

I have never herd of anyone having the issues you state and I have run my tank to 4 gallons left not an issue in the world. ( 1/6th of a tank )

And by the way a factory 1982 tank never had baffles or surge control. And personally I never run my car or company truck below a 1/4 tank out of good habit.

Metalhead140

There's several posts in threads on this forum by people who have said they do have that issue with the 1982 pickup and a high flow pump - I've been doing quite a bit of reading on it. I hear you that you don't find it a problem, and that's good, but for me it is not an issue I'm willing to risk or accept. I often run my vehicles well below 1/4 tank, and have deliberately competed my vehicles at times with little fuel in the tank for weight reasons.

7t2vette

I've never understood people that spend $$$$$ building an engine that will be EFI, and then not do some sort of sump/baffle in their tank. For the time and cost involved to do so, it just makes no sense to me not to. No modern OEM builds any EFI vehicle without one. Why even take the risk? I certainly wasn't willing to.

I personally know several people that have this issue, and had to do it again properly. One of them told me about the Rock Valley fuel pump module/sump kit he ended up putting in his '69 vette, and after looking at it, I decided to do the same.

I went with the fully stainless internal fuel pump module/sump kit from Rock Valley because of the design that traps fuel around the pickup. At the time, it cost $375 including the Walbro 255 LPH pump, and is very well made. It is made to fit into the stock tank. If my tank wasn't basically brand new, I probably would have went with the complete Rock Valley SS tank and fuel pump module/sump. I had my local race shop weld it in my tank for $50, then I custom bent SS hardlines for it. I then painted the tank.

































No problems with this set up after a almost 6yrs of use. The pickup has never gone dry under any situation, and I have ran it almost completely empty a few times; once less than 1 gallon in the tank!

diehrd

GM made a system that works perfectly . I make a lot of power have Multi port sequential injection and never herd , had or for see an issue.

And I have not seen people on this forum complain with the stock set up maybe people can post up those topics so we all can see what there problems are.

Metalhead140

Do we really need an argument? A few seconds of searching along the lines I had been (1979 Corvette fuel injection) found:

https://www.corvetteforum.com/forums...-question.html

And this:

https://www.corvetteforum.com/forums...nk-issues.html

In the first 2 links that came up for my search. TBH, there are others in those links who say it's ok. But there's also lots of people reporting similar problems using an external pump with the standard pickup, which I'd expect to be similar. And of course, there's also people saying that running an external pump with the standard pickup is fine. I guess it depends a lot on driving and filling habits. I know I will drive my car hard, and down to very low in the tank, so I want that extra margin of safety, for me.

diehrd

Two guys one says.

Nearly empty or very low Bahahahahaha that proves your point


Second guy says almost the exact same thing "if I am Real low on gas"

read every reply my posistion is supported solidly yours well sure by 2 guys running the cars almost out of Gas ,, Bahahahahaha ,,,, LMAO ............

Look the 1982 sender is perfect for 99.9% of c-3 owners , It works perfectly fine as that topic confirms .

Metalhead140

I'm glad it's working for you. What pump are you using in your setup, and what pressure can it support?

Anyway, I've been looking at the modern GM pump drop in assemblies. Has anyone gone this route on a 78-82 tank, or is it not easy to do with the bladder in the tank? I can get an assembly, modified for greater tank depth and return fuel system, and with a higher output pump to support my engine, from a local supplier for significantly less than the Aeromotive in tank setup.

diehrd

I used this pump .
http://www.fuelairspark.com/fas/in-t...ector-kithtml/

Domobomb

I'm also looking at fuel delivery. I have a '78. There is no Tanks Inc option for that year.

Will the Aeromotive Phantom set up work?

gbarmore

I'm curious about the Aeromotive Phantom set-up as well for my 80. The tank is pretty deep, but not sure how deep. Specs on the Phantom unit is up to 12". Anyone have direct experience with this? I shouldn't have to be asking this as I've already installed (not run yet) the FiTechGo EFI 600 fuel command center, but i'm expecting the worst here and figuring I will end up starting over with my fuel delivery based on the experiences of others here.

7t2vette

Shark Racer posted this in another thread:

Quoted from this thread:

https://www.corvetteforum.com/forums...-concerns.html

I realize that the Rock Valley kit I installed on my tank won't work on the 78- 82 tanks, but has anyone contacted them to see if they make one that will?

http://www.rockvalleyantiqueautoparts.com/ndex.htm

Using an '82 sending unit modified somehow to work with Holley Hyrdamat might also work:

https://www.holley.com/products/fuel_systems/hydramat/

Maybe an '82 sending unit can be modified to include a sump; this fella came up with a rather clever DIY mod to a 75-77 sending unit:



From this thread:

https://www.corvetteforum.com/forums...a-75-to77.html

diehrd

You are all placing an excessive amount of importance on a sump. How many run there tanks to E ? How many road race for extended time ?

How bad would it be if you had to fill up at 1/8 or even a 1/4 tank ? The 1982 sender works in the 78 to 82 cars perfectly. I am around 600HP Multi port sequential injected and never have had a single issue with the 1982 sender and a quality fuel pump.

One fill up was 21 gallons meaning I had only about 4 left in the tank and although I new I was pushing it I had no loss of fuel pressure at all..

rdicarlo

agreed. I'm thinking about placing a resistor inline on the sending signal wire to make my fuel gauge show empty even when I have a 1/8 of a tank. or I might bend the float rod before I drop in the 82 sending unit.

gmtech1234

I don't think a resistor will fix that issue. Higher resistance drives gauge to full. ( 0 ohms empty, 88 ohms full ) Bending the rod could work.

Metalhead140

Mate, you've made your point, but there's no need to belittle others sharing different information. Personally, I normally run my cars down to 1 gallon or so left in the tank, your 4 gallons left is over half the tank in one of my other cars. Your way is obviously a good way, but that doesn't mean it's the only way. I do compete at track days and other events where considerable time is spent on the track. Some of these here in Aus would be over half an hours drive from a petrol station. Road trips here might mean quite a few km between decent high octane fuel, and I'd like the ability to run the tank as far as I can. Yours is a good option, easy and cheap, and I'll seriously consider it, but I want to look into all options available and would appreciate you not bashing any viewpoint that isn't your own.

carriljc

I installed an in-tank Bronco cannister-type-fuel-pump to feed my RamJet 350 in the year 2003.
The fuel return goes back into the cannister and so there is no need for baffles, and also, I was trying to avoid making a sump when I did this.

Before that, when I had a Holley Pro-jection and I was using an external fuel pump - THEN I would lose suction if I took a corner fast and my tank was <a quarter full.

As mentioned in the post - if I was to do it today I would just use an 82 sending unit and modify it to hold the Bronco cannister pump assembly. This has worked quite well and I have removed the pump, and reinstalled it from the top-- no need to drop the tank.

I tested this by running it out of fuel. I did not lose fuel pump capability until the tank was sucked down to the bottom -

just something else to ponder.

https://www.corvetteforum.com/forums...for-efi-2.html

diehrd

I am not bashing , I am pointing out a factory solution. Do you see me posting up photos ? Or showing off ?

Fact is your rare , very few people run a old cars gas tank that low and the reasons are many .

GM solved this issue I offer it up for everyone to see because it not only works it saves a ton of time and money

Domobomb

Thanks for the info mate. Appreciated.


I will be auto crossing the car, so that is not an option for me.

lionelhutz

The fuel module is by far the best factory setup. These have a jet siphon pump that keeps the canister full of fuel no matter what the tank level. There is a reason all the manufacturers switched to these modules and that's because they work until the tank goes dry compared to simple baffles which can start stumbling as the tank gets low. Here are examples of retrofitting one into an older tank.

http://vetteworksonline.net/ls1_conversion_fuel.htm

http://www.gearhead-efi.com/gm-ecm-p...onversion.html

I looked at solutions like putting baffles or a tin can around the pickup but came to the conclusion that it would help but not stop fuel starvation as the tank gets low. I was working on a really flat tank so the fuel sloshes a lot. My first setup was a simple external pump to get it running and I could get it to stumble with over 1/2 tank of fuel in it. I then adding a sump to the tank and that stopped all the issues I had. My tank is too short for a pump module without adding an extension sump to the bottom anyways.

Now, that Holley HydroMat sure seems like a great solution and rather simple to apply. I would have likely used one if it was around at the time. For a C3, using one of these and running the new return line can't be more money than the FCC.