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Old 04-25-2010, 11:24 PM   #1
FC Zach
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Fuel Pump Options?

From the time I converted my FC to the Holley set up (since about 2004), I have tried two different pump set ups. The first assembly was an Areomotive external and I thought it was toooo loud and over-kill. From that experience I decided that I wanted to go with an in-tank pump. Options are limited when it comes to in-tank low pressure pumps. The one pump that I knew of off the top of my head was the TBI GM pump. These pumps are FI pumps that run at low pressure (around 15psi typically) and are readily available at any auto parts store. I ran this pump for a little over a year. The only problem with using this pump on a carbureted car is that It holds pressure once the car Is shut off due to a one-way valve from within the pump (as it was intended to be since it was made for FI vehicles). I had solved this problem by using a "ghetto" by-pass to return fuel back to the tank to take unnecessary pressure off the floats when the car isn't in use. The problem that arose from this was an inconsistent fuel pressure. So because of that, today I decided that I am going to fix that little problem. So I thought. My plan was to remove the check valve from within the pump and return my FPR back to its original state. This didn't go as planned, and became nothing more than an experiment. The pump no longer works and now I am back to the drawing boards.

There are two different options on my mind at the moment. The first one will be new to me and that involves using the factory FC pump with a new FPR that is designed to safely reduce fuel pressure without destroying the pump. The only problem with this idea is I do not have a good FC pump and neither do the locals so this would mean I would have to purchase the new pump and that fancy FPR (I really dont want to have to do this). The other idea is to just simply buy another GM TBI pump but use a real bypass regulator instead of the crap I have on the car now, and again I really dont want to have to do this either since I am going to have to purchase another pump due to the failed experiment and a new FPR.

I would like to retain my FPR and just purchase a new pump. An in-tank pump designed for carburated applications would be nice. The only problem is, I dont know of one. Any Ideas would be greatly appreciated. After doing some searching I stumbled across a Volvo pump that had a low PSI rating, has anyone heard of anyone using this? If so does it have a one-way valve in it?
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Old 04-25-2010, 11:52 PM   #2
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whats the GPH and psi your running or wanting to run?
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Old 04-26-2010, 12:02 AM   #3
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What about trac hore its pump might still be good. Also if you switch fpr i call dibbs haha
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Old 04-26-2010, 01:11 AM   #4
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Quote:
Originally Posted by 85'12a-Blake View Post
whats the GPH and psi your running or wanting to run?
The Aeromotive pump I had was 120 GPH i do believe and the pressure I had the regulator was set around 5 PSI. The TBI pump that I had in the car prior to today, specs unknown but pressure roughly the same (5 PSI). I want to run something with a reasonable GPH, it doesnt have to be too outrageous. The pressure will stay around the same PSI.

IH8DSM "What about trac hore its pump might still be good. Also if you switch fpr i call dibbs haha"

The Track Whore's pump was taken out today. It is NO BUENO! the thing was nothing but a ball of a tar like substance and it didn't even resemble a pump. Robert says he may have a N/A FC pump he can donate. If so, I may go that route but still would like to know what/ if any pumps are out there that are usable in-tank pumps for carb applications. If I do go with the fancy by-pass regulator to use with the stock FC pump you can have my Aeromotive FPR.
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Old 04-26-2010, 06:43 AM   #5
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I 'had' and FC pump, but I dropped it and now the plastic outlet has a stress mark on it...so I wouldn't use it.

Maybe Paul can find you something here at work. Send him a text.
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Old 04-26-2010, 08:11 AM   #6
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Zach we'll need to talk about exactly what you want to do, and I may have something for you.
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Old 04-26-2010, 08:30 AM   #7
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I can't help but think that as long as you are trying to produce huge pressures from the pump, then drastically reduce them via a regulator, you are going to have issues.

http://www.rx7club.com//showthread.php?t=529605

That's a writeup I did on the Carter pump/Holley regulator installation. But it might not be of use to you since you want a quiet pump (those Carters are LOUD). However, if you contacted somebody with the knowledge (like maybe Summit or Respeed) and tell them you need a pump similar to the Carter but quieter, they might be able to steer you in the right direction.

I have also heard that it makes a difference whether or not you run a return line. So make sure you get that straight.

But overall, I think you will be much better off using a pump that gives you what you need, without going too far overboard. Too much pump will just cause strain in the pump, use more juice to run it, then have to be tamed down by an overworked regulator. But, I don't have gobs of experience in this, so maybe I've got it all wrong.

Best of luck with your project....



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Old 04-26-2010, 05:21 PM   #8
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I'm a big fan of Carter pumps. They're not that loud if you mount it on the frame rail and insulate them really well (use more than just the little grommets it comes with, they're not enough). I ran one in my FB before I went turbo and it was an audible but quiet hum at idle, couldn't hear it at all when cruising. It also quiets the pump down a lot if you use a return-style FPR like the Mallory 4309 that I'm using now.
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Old 04-26-2010, 05:29 PM   #9
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Smile

Quote:
Originally Posted by Kentetsu View Post
I can't help but think that as long as you are trying to produce huge pressures from the pump, then drastically reduce them via a regulator, you are going to have issues.

http://www.rx7club.com//showthread.php?t=529605

That's a writeup I did on the Carter pump/Holley regulator installation. But it might not be of use to you since you want a quiet pump (those Carters are LOUD). However, if you contacted somebody with the knowledge (like maybe Summit or Respeed) and tell them you need a pump similar to the Carter but quieter, they might be able to steer you in the right direction.

I have also heard that it makes a difference whether or not you run a return line. So make sure you get that straight.

But overall, I think you will be much better off using a pump that gives you what you need, without going too far overboard. Too much pump will just cause strain in the pump, use more juice to run it, then have to be tamed down by an overworked regulator. But, I don't have gobs of experience in this, so maybe I've got it all wrong.

Best of luck with your project....



.
I checked out the thread. I'm focusing on in-tank pumps only. So far my only options (that I know of) are to run a OEM FC pump with an Aeromotive A1000 Bypass Style Regulator. Or go with another GM TBI pump and use any universal bypass style regulator. I totally agree with you about running a return line. It's so much more consistent and I like the fact that it will keep the fuel/premix circulated well. Again, I am definitely on the same page with you on the last comment. The FC pump will give me what I need (quiet, in-tank, not voltage hungry, and DIRECT FIT!) butttt, , ,, , the regulator will be redirecting a mass volume of fuel and I'm not even completely sure that the Aeromotive A1000 will safely do this. Oh yeah, almost forgot to mention that this regulator is $150.00. If I have to purchase the regulator and a brand new pump, this set-up is obviously going to be the more expensive route. So there you go, there are perks to just about everything. I just have to figure out what option has benefits that out-way the tribulations.

Thanks for the in put guys, if you have anymore ideas, hit me with it.
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Old 04-26-2010, 08:47 PM   #10
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You need a lower pressure pump (like a TBI), or make a pickup again and use an external pump. I'll see if I can find a pump around 10-15psi (or whatever to ensure fuel volume) without holding pressure. Then you can use return-style regulator and be done.
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Old 04-26-2010, 10:09 PM   #11
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According to the website, their FPR will work with EFI pumps. If Robert still has a good pump, I may go this route. Which will be good because the main purchase will be the FPR.

Paul, if you find a pump, that will be great too. Especially if it doesn't hold pressure, then that will mean that I wouldn't necessarily need to buy a bypass style regulator and I could keep the basic Aeromotive FPR I currently have now. Although I do like the consistency of bypass regulators.. .. .

Since I'm favoring the bypass regulators, it looks as though either set-up (OEM FC pump w/ A1000 FPR vs. TBI and any universal bypass FPR) is going to cost me about the same. I'm just confused right now, I'll figure something out!
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Old 05-05-2010, 10:39 PM   #12
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Quote:
Originally Posted by FC Zach View Post
The only problem with this idea is I do not have a good FC pump and neither do the locals.
How do you know when you dont even call and ask??????????
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Old 05-06-2010, 01:04 AM   #13
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Quote:
Originally Posted by fire85gslse View Post
How do you know when you dont even call and ask??????????
Didn't even think about it. Hey Chad, do you have a FC pump!?

So I finally figured it out. After doing some research on Aeromotive's website and seeing that their bypass regulator (part # 13204) is for people doing the same as I. I'm going to roll with this regulator and the OEM FC pump, and with a little modification to the fuel return this should work great! It should in theory be WAY more efficient than the previous set up I was running. I'll post whether or not it does. Thanks for the input guys!
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Old 05-06-2010, 09:06 PM   #14
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Quote:
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Didn't even think about it. Hey Chad, do you have a FC pump!?
yep and also have something else that might work better over all and cheaper.
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Old 05-06-2010, 09:43 PM   #15
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I have already made up my mind on the set-up, I have already purchased FPR and all the required AN adapters and fittings. Just out of curiosity, what do ya have?
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