EFI and Electric Fuel Pumps...

[Derek69SS]

Teach me all I need to know, experienced ones. :hail:

I'm putting a stock (for now :unibrow: ) '95 LT1 in my '69 Chevelle. I was told to run an in-tank pump rather than an in-line. Why? I don't know... something about heat and reliability.

I've got a new tank that I can weld on if I have to. It's new, so I won't explode myself. :willy: <--I like this little guy, I use him somewhere in all my posts...

What do you guys recommend I do? jimmy-rig the stock caprice pump into the chevelle tank? Got any ideas that are cheap and easy? Emphasis on CHEAP... and EASY... don't forget EFFECTIVE

I don't want to constantly have to haul a cooler of ice in my trunk with my fuel line coiled inside :P

[LVCamaro]

If I were you I'd throw that in-tank pump as far as you can throw it. Jody and Scott would be glad to help you dispose of it after what they've been thru with the Chevelle on HRPT. The in-tank theory sounds good on paper, but I've given up on depending on them in real time.

SS

[Musclerodz]

The question is, why do they work so well in hundreds of thousands of production cars, but we can't get them to work in our Hot Rods? Routing too close to exhaust? Running too small of a pump requiring to work extra hard? Installing too small of a fuel line so the flow isn't correct? :willy: :willy:


Mike

[69MyWay]

I would suggest installing a complete gas tank from a 1988-1996 Caprice in the car. The fuel inlet will go behind the license plate. There will be some minor mods but it will go.

I was able to squeeze a plastic tank from a 1996 Caprice in my 69 Camaro with some mods to the tank and to the trunk. Your car is much larger so you should do great. The older caprice tanks are metal with the intank pump.

They have great baffles that prevent fuel starve in corners.

You can then run a stock replacement pump.

If you cut your trunk and make and access door you will be able to service the pump without dropping the tank.

I was able to run a Walbro High end pump that dropped in the stock housing to feed the higher pressure demanded by modified LS1 engine.

Give this a shot!

[Derek69SS]

I think I'll look for an 80s caprice metal tank to try. I did a little measuring on the plastic tank of a '92 caprice I parted out, and it would hang below the bumper in plain sight.

[Rybar]

You can try this install with your Chevelle tank:

http://www.thedetailzone.com/Tanks%20Fuel%20Pump%20Install.htm

[69MyWay]

It does hang down, but I think it looks kind of cool there.

I like what Rybar just posted though very much. Nice way of doing it all in one. I am running that 255 pump in my car.

http://www.mcspeed.homestead.com/files/fuelcell2.JPG

[RickWI]

The problem, as was encountered on Power Tour this year, were the very high temps, espcially through Dubuque stop and go traffic combined with very high underhood temps and return lines located in engine compartments. This is compounded by many of us running pumps that need to supply enough fuel to support 700-900 HP at full throttle but at idle we are utilizing only 1/100th of that capacity. Therefore all that heat that gets picked up by the return line is transfered to the fuel. at a rate of about 100 gallons or more per hour. On this leg of the tour I had underhood temps exceeding 150-160 degrees based on my intake air temp sensor. After time that heat from the returning fuel builds up in the tank to the point you can't even touch the bottom of the tank. On top of this the trunk is packed full of suitcases, coolers, booze, tools and everything else under the sun, compounding the problem even further. The end result is it starts taking out the pump.

The ultimate solution is to plumb a "returnless" style system as Mopar and other do. The return is kept back at the tank with the regulator located there as well. This greatly reduces/eliminates the hot tank syndrome that plauged many of us on this year's Power Tour.

Also, another excellent pump is the Bosh 0-580-254-044. Extremely quiet, reliable and run by the IRL boys.

Actually, for Jody et. al., for that pump to survive like it did is amazing. As far as I know, through Nashville, the pump was still going strong after they sorted the situation out. The pump was never the problem. The environment it had to live in though was brutal.

If at all possible you will want the pump inside the tank. 99.9% of the time it will stay cooler and also will be nice and quiet.

[Blown353]

Rick, I don't think the problem so much is the heat taking out the pump, but the temp of the fuel exceeding its boiling point; thus, you boil the fuel and get vapor lock. Fuel pumps can't pump vapor, and when they start pumping boiling fuel the pump cavitates, which is what ends up destroys the pump as all the internals basically get "rattled" to death.

With some of the newer emissions formulations for gasoline (oxygenated especially), fuel boiling points can be as low as 135-140ºF. Considering your engine is probably at 180-200F, and you're pushing a lot of fuel volume, it doesn't take long to heat soak the fuel when there's not a steady stream of cool air over the gas tank to cool it as it would be when you're driving down the freeway.

Another solution is a fuel cooler. Just run the return line from the regulator though a cooler mounted on the front of the car (or hidden out of sight with a fan). This is also a good solution, but it makes me a bit nervous as it creates yet another potential leak spot. Luckily the return line is low pressure so if a leak develops at the cooler it should only be a dribble, rather than a spray as it would be on the high pressure side.

Troy

[pushrod243]

Add my Car to the list of efi cars on the side of the road on the power tour. After 20 mins we were off and running. I have to find a fix yet. I was still trying to figure out exatly what was up. I wasnt sure if the return was to small since I am running a a1000 Aeromotive pump and a stock Ramjet 502 regulator. Aeromotive suggests running thier regulator back at the tank and deadhead the fuel rail. I wasnt too crazy about that so i tried the stock reg setup first which has performed fine until it got hot outside. I guess its time to spring for a tank and stick the pump inside it.

[Blown353]

Actually, installing the regulator back at the tank will probably keep fuel temps substantially cooler as you aren't constantly circulating fuel through the hot fuel rails and lines up in the engine compartment.

On a setup that doesn't need a boost-referenced regulator, that's not a bad way of solving the fuel heating issue.

The regulator at the tank and deadhead at the intake may pose an entirely different form of vapor lock problems; i.e. you park the car and engine heat boils away the gas in the rails and injectors. With a "normal" setup, when you turn the key on and the fuel pump cycles fresh fuel is circulated through the rails clearing the vapor so you have fuel at the injectors when you go to crank it. With the deadhead install Aeromotive recommends, you may have to crank it a bit until all the vapor is expelled out the cycling injectors and you get good fuel into the engine-- then it will start.

I still think a fuel cooler, along with a PWM pump speed slow-down for cruise conditions is the best option... and with the cooler sized appropriately and given good airflow it should keep your fuel tank at ambient temp at all times. That's a good thing. :)

[RickWI]

Rick, I don't think the problem so much is the heat taking out the pump, but the temp of the fuel exceeding its boiling point; thus, you boil the fuel and get vapor lock. Fuel pumps can't pump vapor, and when they start pumping boiling fuel the pump cavitates, which is what ends up destroys the pump as all the internals basically get "rattled" to death.


That certainly was happening in a lot of cases as some gas tanks were too hot to touch and is where I was going in my thoughts. Mine never got THAT hot but on restarts you could hear (with my old pump) it caviating trying to build pressure and see the pressure struggle. After we changed the pump though we never had a lick of trouble, that is until the reg started squirting out the vent, damn that was a scrape to get parts (thanks Jay from FAST). But, AFTER THAT issue we never had any more problems.

I like the idea of the modulating controller. That's a pretty pricey device but taking out $500 pumps and being stranded is as well. I don't know what the ultimate solution really is but I can attest to some creative fuel can coolers in use that did an amazing job, for not a lot of money either. course the beer will be warm when you get to the next stop that's for sure. :yes:

I don't know the thermodynamics of all these boutique fuels that are out there right now, although I know in So IL the fuel stalled the car out and I needed two cans of Klotz to get things back to normal, but I suspect once cool fuel is pressurized by the pump the boiling point would be raised quite a bit. With the returnless system that may be what keeps them out of vapor lock under low load type conditions. Since I got this new Bosch pump I need to call them to get the flow curves on it. Next week I'll give them a call and ask them about the situation on Power Tour and get some feedback from them.

I think though that you have to put into perspective what we were doing on PT this year, driving for 6-8 hours at a time in 90-95 degree temps, sometimes at 2 MPH, sometimes at zero stuck on the freeway and sometimes at 120 racing Nancy in her Nissan to get a better look at her. It was a pretty taxing environment that I have never experienced before in a highly modified car. I do think the answer is in the OEM designs for whatever reason, although I really need to take a closer look at them in detail. I didn't hear of anyone with a stock OEM production car having any issues. One that was stock or close to it that is.

[Rick@Rick's Hot Rod Shop]

One thing that could AID is a Fuel Pump Speed Controller Aeromotive Speed Controller (http://216.242.145.16/products/product.phtml?p=31)

[pushrod243]

So to all the fuel experts out there...... I am planning on completely redoing my fuel system from the tank to the regulator whether its on the fuel rail or in the tank like Rick's tanks are setup. The problems i am faced with is I am going to install my turbos next so the fuel system will need a boost reference regulator and enough fuel volume to support 900+ hp. Local advice is to run two aeromotive pumps since i already have 1 A1000 pump on the car now. But i dont think i have room for 2 a1000's. The pump currently is mounted outside the tank and my car was one of the ones on the side of the road on the power tour so i have to fix the heat problem too. I was wondering about the Bosch pumps but cant find much info on them. Any ideas would be helpful.

[RickWI]

Call Earl's Performance in Indy 317-241-0318 The pump I got as model # 0-580-254-044. That's where I picked up mine. I paid $258.90 for it.

[clill]

We put two bosch pumps on the Mule and the side of the road problem went away. They are the pumps used on the Porsche Twin turbo. I can try to get a part #. The Mule is at Wheel to Wheel so maybe we can bug Kurt to take a pic and show how they are mounted. The part I like the most is if one decides to quit I can just go under the car and swap wires so the second pump becomes the main pump. They seem to put out more than enough fuel for the Mule and they are a spec pump for a production car so they are probably more dependable that most of the aftermarket stuff. Aeromotive is probably fine for a drag car but it doesn't like sitting in 100 degree traffic for hours..

[427]

Charley's Camaro has one simple fix in the two pumps. The second pump does not start until you exceed 3psi boost.
I have a seperate tank in my truck about 1 gallon in size. Inside it houses two Walbro 340 pumps. One is on with the key, the other comes on in boost. This system is quiet in operation and has the ability to feed the power the engine will produce(750hp) with a comfortable safety margin. The tank is kept full by the factory pump in the tank, giving me cornering slosh control second to none.
The regulator back at the tank is a good fix for Power tour cars that are not boosted. The boosted one's may want to try a regulator under hood with a semi dead head system. Make the return fuel not go near the engine or any of its components, paying close attention to headers. This would still give a underhood mounting for boost referenced fuel pressure.
Last, the Aeromotive pump is "fragile" to heat problems. It is a great product for racing cars but has some problems with warm fuel.

Kurt

[pushrod243]

thanks guys i like the bosch pump idea seems simple enough and using regulator near engine but not on it. I take it your pumps are external Charley? I plan to put a new tank in the car since mine is leaking now. What turns the second pump on the ecm or a hobbs switch or ??? I am looking at an accell dfi because that is what my tuner suggests but really would rather run ther big stuff unit. He says hes more familiar with the accell and would rather tune it. He also has a new one that was never installed including harness for $1100 but if its wont do everything i need then id rather spend the money the first time on the right unit. Also what do you suggest to run for a boost reference regulator? I had Aeromotive stuff in mind but you guys dont seem to think very highly of its pumps driveablity is the regulator ok?

[427]

Charley's pumps are external.
Second pump is on hobbs switch.
Regulator's, my favorite is the Weldon if it fits, the Kinsler if space is tight.
The Big Stuff 3 is my choice, mostly because its easy to use.


Kurtthanks guys i like the bosch pump idea seems simple enough and using regulator near engine but not on it. I take it your pumps are external Charley? I plan to put a new tank in the car since mine is leaking now. What turns the second pump on the ecm or a hobbs switch or ??? I am looking at an accell dfi because that is what my tuner suggests but really would rather run ther big stuff unit. He says hes more familiar with the accell and would rather tune it. He also has a new one that was never installed including harness for $1100 but if its wont do everything i need then id rather spend the money the first time on the right unit. Also what do you suggest to run for a boost reference regulator? I had Aeromotive stuff in mind but you guys dont seem to think very highly of its pumps driveablity is the regulator ok?

[clill]

Kurt..Can you drag your ass under the car and get him a pic ? :D

[427]

To busy driving it!!!


KurtKurt..Can you drag your ass under the car and get him a pic ? :D

[clill]

Jackass................