holley projection

[jeepboy45]

Hello fellow Jeepers....

I've got a couple of questions for those who might have experience in this area.. I've got a newly rebuilt 360, and I'm going to install a used Holley Projection system.

The setup comes with an electric fuel pump. Directions are specific about mounting it at or below the lowest part of the fuel tank. Years ago I installed a 20 gallon factory poly tank from a later model CJ. There is no part of the frame that sits lower than the bottom of the tank. A Holley tech told me that I needed to put it lower, OR get a "sucker" type of pump instead of using the gravity fed Holley..

Has anyone put on a Holley or Howell setup and used the gravity fed pump NOT below the tank???



I was toying with the idea of an electric pump mounted in the tank. Recently I've changed a couple of GM pumps in my older van and Tahoe. I really like the idea of a factory pump for reliability, and would like to be able to have one mounted directly in the tank like GM (and I'm sure Ford) does.

Does anyone have any imput on retrofitting a stock Jeep tank to accept a pump from some other applicaton.

I modified the Holley wiring harness and it is all soldered in. Now I just need to finalize mounting the pump, and I'm ready to go..

thanks very much for any imput.

Brian

 

[gert]

I bought a YJ gas tank recently with the pump assy. I am planning to go TBI and looked at the pumps from the GM trucks of that era and they use the same style pump. My plans are to just remove the high pressure YJ pump for the lower pressure TBI pump. They both look like Walbro pumps Havent got around to mounting the tank, I have heard that I might have to move one of the support bars by 1" Also if you look at the Howell kit which I have installed before they sell you a frame mounted Walbro pump which is pretty easy to install on the frame rail in front of the gas tank

 

[Torxhead]

Installing an in tank fuel pump is the best way to go. I would suggest a search on the net for what you are looking for. The CJ oem tank is of course not not designed for such an upgrade. The fuel level sending unit hole is too small and it is not baffled for an electric pump, but yet some guys seem to make it work with a few modifications. I have the low pressure Howell setup with exterior pump and it has worked fine for about the last 10+ years. Good luck with your conversion.

 

[ThisGuyUKnow]

If you mount your pump on the frame rail on the pass side it should be low enough to operate. Yes it will sit a little higher than the bottom of your tank but the idea is that once the pump is primed gravity helps to pull the gas out of the tank.. Like when you siphon gas you initially have to suck real hard but once you get it flowing you no longer have to apply suction to to keep the flow going. Same concept here. Once the pump gets prime the siphon affect helps to relieve stress on the pump.

I had a low pressure fuel pump on the frame of my wagoneer for years and it worked great. It was mounted about on the frame rail and was about midway on the tank height.

At least that is what I think someone might have a different opinion. But this has been my experience.

 

[jeepboy45]

Thanks for the responses so far... Holley tech was adamant about placement and he had me believing it MUST be below tank height. I should probably give it a try before doing all the gas tank converting.

I still like the idea of the pump in the tank though..

thanks again
Brian

 

[ThisGuyUKnow]

Thanks for the responses so far... Holley tech was adamant about placement and he had me believing it MUST be below tank height. I should probably give it a try before doing all the gas tank converting.

I still like the idea of the pump in the tank though..

thanks again
Brian

Below tank height? or Below the bottom of the tank.

I keep seeing posts online where people make the statement similar to the one you made about inline vs in tank pumps.... My response is why? You are doing a non stock conversion in your jeep. In my experience it is best to keep things functioning as close to stock as possible to reduce the risk of failure later on. In the case of an in tank pump you have to either somehow modify your sending unit to house a pump or find a tank to convert into the jeep. This requires you to drop the tank which is a PITA and time consuming. Especially so if you are converting a tank like that yj one you bought.

If you get intank pump to work and it burns out or fails, you now have to drop the whole tank again to replace it.

An inline pump is fairly easy to install on the fuel rail or the crossmember above the rear pumpkin. It requires you to modify virtually non of your major components and will take you a fraction of the time. I personally have not had one fail on me as of yet (knock on wood) but I know alot of people say they are more prone to failure as a negative... This is because they have to suck instead of push fuel to get prime which is a little more stress on the pump. By mounting it below the top of the tank you can extend the life of the pump.

If you are super paranoid that the pump will burn out and leave you stranded by a spare and keep it in your glove box. You could buy 3 pumps and still not have spent in terms of time and money as much as you will invest in an intank set up. If it fails, its pretty quick to swap out the spare pump.

Another negative that people bring up against inlines is how loud they are. When you turn on the pump you can hear it running but once you start the engine its hardly noticeable, at least in a a CJ7 . I have never driven my cj with the inline pump and said wow that pump is really loud right now.

 

[jeepboy45]

Below tank height? or Below the bottom of the tank.

Holley says below the bottom of the tank. If I mount it on drivers side above my TC skid plate, it is only a couple inches from being BELOW tank bottom... I should prob try it.

I have never driven my cj with the inline pump and said wow that pump is really loud right now.

Holley says below the bottom of the tank. If I mount it on drivers side above my TC skid plate, it is only a couple inches from being BELOW tank bottom... I should prob try it.


FUNNY statement. Especially with exhaust coming out the drivers rear, PLUS the flex-a-lite fans I can hear when I am sitting at a stop light.... I'll never hear that pump..!!

thanks

 

[harleydragon]

you will probably hear the pump but it's not bad.It just blends in with the other sounds..the inlet of the pump needs to be lower than the bottom of the tank or at least lower than the level that you ever intend for the fuel in the tank to drop to..think of it as if you were siphoning gas,the outlet must be lower than the level you are siphoning from..it needs to be the lowest point of any of the fuel system

 

[oss]

You don't have the tank on top of your rig, that's why you need the pump. If you can put the pump under the tank it would be the perfect placement, but this is not a perfect world. So put it as close to the tank as possible and call it good. My $.02.

 

[ThisGuyUKnow]

So funny enough after talking up inline fuel pumps. They one I was using in my TPI project seems to have shorted out and I haven't an hour on it. I think I just got a bad pump but still. So I guess I will need to replace it.

Im Still pro inline pumps though

 

[jeepboy45]

So funny enough after talking up inline fuel pumps. They one I was using in my TPI project seems to have shorted out and I haven't an hour on it. I think I just got a bad pump but still. So I guess I will need to replace it.

Im Still pro inline pumps though

I'm leaning towards in the tank pump, but havent really decided yet.. I'm still sitting at a computer desk reading information instead of underneath my Jeep actually getting something done!

 

[biggwrench]

I ran a early holly projection (analog) for about 12 yrs. ,mounted the pump on the frame rail near the skid plate -worked great at all angles .The only mod to the system -I upped the fuel lines to 3/8 feed and return. My understanding about the pump location. The lower and closer to the tank the less chance for vapor lock ,because more line is under positive pressure.

 

[jeepboy45]

I ran a early holly projection (analog) for about 12 yrs. .

Did you get rid of the setup?
Tired of it?
Back to carb?