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Discussion Starter #1
(This question is not about my '55 but rather my '96 LT1 powered 83 El Camino.)

Will a TBI electric fuel pump work for an MFI engine like my LT1? Are the pressures the same?

I have an in-line pump now but am thinking about going to an new 87 tank that used a in-tank pump. But the engine that year was a TBI.

I know the volume shouldn't be a problem since that same TBI fuel pump was used for V6, 305 and 350ci TBI engines but it is the pressure I am not sure about.

If the pressures are different and I should use a pump designed for a MFI engine instead, how hard would it be to adapt it to the stock '87 sending unit that is designed to mount the TBI pump?
 

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The gm tbi pumps are designed to run around 12 psi and the ones for some of the 454 tbi run 30 psi. The tbi pumps dont have a good reputation for longevity and high flow even in a tbi setup ( I've had several tbi equipped cars and never had a fuel pump failure though) so you really need to get a pump that normally used in a 43+ psi application. You can use a higher pressure mpfi pump on a tbi as its regulator will drop it down to 12 psi anyhow.
The guy sells a large selection of fuel pumps.
http://www.autoperformanceengineering.com/

Regards, Robert
 

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Discussion Starter #3 (Edited)
The gm tbi pumps are designed to run around 12 psi and the ones for some of the 454 tbi run 30 psi. The tbi pumps dont have a good reputation for longevity and high flow even in a tbi setup ( I've had several tbi equipped cars and never had a fuel pump failure though) so you really need to get a pump that normally used in a 43+ psi application. You can use a higher pressure mpfi pump on a tbi as its regulator will drop it down to 12 psi anyhow.
Regards, Robert
Thanks Robert. That helps.

I'm getting info on the ElCamino Central forum now. They say the Walbro 255lph EFI pump will fit a stock El Camino sender.
 

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Careful!!

Thanks Robert. That helps.

I'm getting info on the ElCamino Central forum now. They say the Walbro 255lph EFI pump will fit a stock El Camino sender.
there are a bunch of knock-off Walbros out there! [Ho Chi Min specials!]
Furthermore, the Walbro is gaining a rep for not lasting very long. A couple yrs ago, they had a serious qc problem, resulting in a exchange program being initiated.

Here is a link to several threads on the topic...
http://www.turbobuick.com/forums/general-turbo-buick-tech/263358-walbro-fuel-pump-update.html
 

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Discussion Starter #5 (Edited)
there are a bunch of knock-off Walbros out there! [Ho Chi Min specials!]
Furthermore, the Walbro is gaining a rep for not lasting very long. A couple yrs ago, they had a serious qc problem, resulting in a exchange program being initiated.
Wow, that is interesting about the Walbro. However, your link didn't work for me. It could be that I have to join to be able to search.

Well, from the info I got on the El Camino forum, the stock EFI sending unit is no longer available. I would have to fabricate something. I don't want to go through that kind of work right now since I'm concentrating on my '55 project. So, I am back to sticking with an external pump.

Since converting to the LT1 in my El Camino, I have put 25K miles on it over 12 years. I am on my 3rd external pump now since pump #2 died last week when I was out of town. Luckily, when I replaced the first pump that died, I bought 2 and kept the spare in the car.
All 3 of these pumps came from a speed shop and I have no idea what brand they are.

I would sure like to go to something that lasts better than what I've been using. Has Walbro solved their QC problems? I just saw this from Arizona TPI:
http://www.aztpi.com/product.php?productid=41
They say the have had good luck with them and it is indeed hot in Arizona.

What about the Mallory? I wonder if that is a quality pump?
http://www.summitracing.com/parts/MAA-4060FI/
 

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I changed the link. Tried it, and it now works...
Roger, if it's a Walbro, it'll be marked as such. If it's an external, it could be a GS-392. i just got 1 for the inj bench. Got it from Summit.
 

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Discussion Starter #7
I changed the link. Tried it, and it now works...
Roger, if it's a Walbro, it'll be marked as such. If it's an external, it could be a GS-392. i just got 1 for the inj bench. Got it from Summit.
Thanks.

That thread actually makes it sound like the Walbro is a good way to go. The company acknowledged there was a problem and solved the issue in short order.
I am leaning towards getting the GSL392.
 

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Discussion Starter #8 (Edited)
A little new info:

I kept the pump that failed last week and there was a number stamped on it (4018).
After doing a Google search, that part number is an in-line pump from Hypertech.
http://www.shop.speedunlimited.com/p-3398-hypertech-4018-universal-efi-electric-in-line-fuel-pump.aspx

Notice that it says it is not compatible with alcohol or methanol fuels. I recently noticed that around here in Texas, even the high grade of gas now says that it can contain up to 10% ethanol. Maybe that is a problem.

More research for me to do.
 

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If your worried about alcohol find a pump for a flex fuel car/truck they are designed to be run on anything from pure gasoline to E85

Regards, Robert
 

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Discussion Starter #11
Roger 1 go to elcamino central to el caphoon has info on tank & sender u need. just ordered tank & sender from Rock Auto.
Bayou elky--my57vet
Thanks.

I had seen that. I think I even posted in that thread.
He actually modified an S10 sender and made it work.

I have already received a new Walbro pump I ordered from Arizona TPI. I am going to hold off with going with an in-tank pump for now.

Also, I did find out that the electric pump I was using (Hypertech) stated that it was not compatible with alcohol fuels. I'm pretty sure most of our local gas is now E10. That might be why it failed so quickly.
 

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methanol ?

To Roger1 did you really mean to say methanol in your post? Ethanol is probably the additive they use for gas. Methanol is a race only fuel that doesn't mix well with gas.
 

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Discussion Starter #13
To Roger1 did you really mean to say methanol in your post? Ethanol is probably the additive they use for gas. Methanol is a race only fuel that doesn't mix well with gas.
Good catch!
I absolutely meant ethanol.

I've been doing some research. It looks like all my local gas is E10 at least. This concerns me for the winter months in some of my stuff that sits.
I've been reading about how it can cause "phase separation" where the resulting separated liquid becomes extremely corrosive and can never be mixed with gasoline no matter what additive you use. There is also no additive that can prevent this process. All of us need to take precautions with this.
The only place we don't really have to worry about this is in our everyday driven cars.
 
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