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OK to upgrade fuel pump on otherwise stock car?

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Old 08-12-2015, 09:41 AM
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OK to upgrade fuel pump on otherwise stock car?

It looks like my '92 RS (305) needs a fuel pump. The car is totally stock right now. I have no set plans for the future, but I would like to work on making the car faster, potentially a 350, TPI, etc. down the road. Would I be safe to install a higher flow fuel pump now rather than have to drop the tank again later? Since it's a return system I don't see why this would be a problem. I was considering something like this:

http://www.summitracing.com/parts/vp...t/model/camaro
Old 08-12-2015, 10:42 AM
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Re: OK to upgrade fuel pump on otherwise stock car?

A good choice by all means. Walbro is a great pump. Also check out a hot wire kit the runs directly from your alternator to the fuel pump for constant voltage. Pumps do not like varying voltages. Will be good for future upgrades.
Old 08-12-2015, 11:07 AM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by Grant2k
It looks like my '92 RS (305) needs a fuel pump. The car is totally stock right now. I have no set plans for the future, but I would like to work on making the car faster, potentially a 350, TPI, etc. down the road. Would I be safe to install a higher flow fuel pump now rather than have to drop the tank again later? Since it's a return system I don't see why this would be a problem. I was considering something like this:

http://www.summitracing.com/parts/vp...t/model/camaro
No can do, it will overwhelm the TBI unit and drive the fuel pressure sky high. They only time a 255lph pump works is when the hose between the pump and sender splits.

A stock TPI Bosch replacement pump is a good deal.

RBob.
Old 08-12-2015, 11:28 AM
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Re: OK to upgrade fuel pump on otherwise stock car?

I missed the TBI part! Sorry!
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Old 08-12-2015, 12:57 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by RBob
No can do, it will overwhelm the TBI unit and drive the fuel pressure sky high. They only time a 255lph pump works is when the hose between the pump and sender splits.

A stock TPI Bosch replacement pump is a good deal.

RBob.
Thanks, that is what I was afraid of. What if I put a regulator inline before it gets to the TBI unit?

Are there any other options for a high flow/better-than-stock pump that can be used with the TBI? I would like to try and get some power out of the 305 since any engine swap is a few years off and I understand the stock pump just doesn't flow that much.
Old 08-12-2015, 02:54 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by Grant2k
Are there any other options for a high flow/better-than-stock pump that can be used with the TBI?
A stock TPI Bosch replacement pump is a good deal.

RBob.
Old 08-12-2015, 03:30 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by RBob
A stock TPI Bosch replacement pump is a good deal.

RBob.
Sorry I missed that you said TPI pump. That's what I'll get then, thanks.
Old 02-28-2018, 09:10 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

So I may be in a similar predicament as the OP except ive got a leaky fuel tank which if I cant repatch with epoxy, then I will be changing out. I figured if I am installing a new tank I may as well upgrade from my stock (92 RS 305) fuel pump. From what I can tell with bolt ons the walbro pump Ive had an eye on will be to much but the stock TPI will work fine with TBI regulator. So is the pump in this link the correct Stock TPI pump ? Summit had multiple acdelco listed under the z28 so im alil confused on the correct one.

https://www.summitracing.com/parts/a...28?prefilter=1
Old 02-28-2018, 09:22 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by RBob
No can do, it will overwhelm the TBI unit and drive the fuel pressure sky high. They only time a 255lph pump works is when the hose between the pump and sender splits.

A stock TPI Bosch replacement pump is a good deal.

RBob.
That is not quite right. the fuel regular will control the excess and return it to the tank.
The regulator is set for about 12 lbs. any more pressure than that is returned to the tank via the return line. The pressure at the injectors will remain at 12lbs.
I have done this many times, it works.
Old 03-01-2018, 12:16 AM
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Re: OK to upgrade fuel pump on otherwise stock car?

I would have expected the return plumbing to be too restrictive to return the excess fuel from a 255 lph (67 gph) rated pump. If the return system is maxed-out, the regulator cannot lower the pressure enough.

The return system is absolutely good enough with the Delco pump suggested--I have that one in my pickup. Far as I know, they're rated about 40 gph at TPI pressure, I suppose a little more than that at TBI pressure.

Last edited by Schurkey; 03-01-2018 at 12:20 AM.
Old 03-01-2018, 09:31 AM
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Re: OK to upgrade fuel pump on otherwise stock car?

If you have no reason to upgrade the fuel pump (ie you are making much more power and need the extra fuel) then you shouldn't do it. It will only introduce the possibility of more problems and with as difficult as it is to replace the fuel pump why even chance it. Stock engines should use the stock AC Delco Fuel pump. Don't buy a parts store brand, only AC Delco. I've replaced 3 fuel pumps from other brands that died before they should have.
Old 03-01-2018, 03:31 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by J-money
So I may be in a similar predicament as the OP except ive got a leaky fuel tank which if I cant repatch with epoxy, then I will be changing out. I figured if I am installing a new tank I may as well upgrade from my stock (92 RS 305) fuel pump. From what I can tell with bolt ons the walbro pump Ive had an eye on will be to much but the stock TPI will work fine with TBI regulator. So is the pump in this link the correct Stock TPI pump ? Summit had multiple acdelco listed under the z28 so im alil confused on the correct one.

https://www.summitracing.com/parts/a...28?prefilter=1
I wouldn't run an AC Delco pump as there are too many counterfeits. Along with being manufactured in china.

Grab a Bosch brand fuel pump for a TPI car.

Note that years ago the AC Delco pumps were good, but this is no longer true.

RBob.
Old 03-01-2018, 03:42 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by Dyno Don
That is not quite right. the fuel regular will control the excess and return it to the tank.
The regulator is set for about 12 lbs. any more pressure than that is returned to the tank via the return line. The pressure at the injectors will remain at 12lbs.
I have done this many times, it works.
I get emails from customers all of the time about too high of fuel pressure. They install a Walbro 255 lph pump and can't get the fuel pressure down. It usually sits in the 24 - 25 psi range. This is with a totally stock TBI unit and return line.

Those pumps are rated at 255 lph at 43 psi. At 12 psi the actual flow is much much higher. Have you seen how small the fuel passages are in a 220 TBI unit. They just can't return that volume of fuel.

Maybe at times they are OK. But why? Maybe inadequate voltage at the pump. A leaking hose in the tank. Or a partly clogged fuel filter. Or even a counterfeit fuel pump that doesn't really flow 255 lph.

Now on a high performance vehicle that is running an external FPR, at 22+ psi. A block off plate on the internal FPR, yes, can use a 255 lph pump. Can also drill the fuel passages out a little on the TBI to help.

RBob.
Old 03-01-2018, 06:29 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

@Tibo Well the plan for maybe 10 years now has been to do far more upgrades than I currenty have on the car. My reasoning for upgrading the pump now would be if I am replacing the tank I figured I'd save the trouble of doing it later. The reason I was asking about the TPI pumps was to verify whether I would have any issues with installing it now or not.

Last edited by J-money; 03-01-2018 at 06:30 PM. Reason: forgot to add something
Old 03-03-2018, 09:28 AM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by RBob
I wouldn't run an AC Delco pump as there are too many counterfeits. Along with being manufactured in china.

Grab a Bosch brand fuel pump for a TPI car.

Note that years ago the AC Delco pumps were good, but this is no longer true.

RBob.
Counterfeits, as in they come in an AC Delco box and are sold by the dealership and major outlets?

I've used the AC Delco fuel pump from the Syclones/typhoons (on Dyno Dons suggestion at that!) and had no problems with them. Meanwhile the famed Holley/Walbro fuel pumps that everyone recommends have never lasted much longer than a year. Perhaps its a "your mileage may vary" issue.

As far as being manufactured in China, I have been under the impression that nearly everything car part wise and tool wise was from either China or Mexico. On occasion over the years I've purchased enough made in China or Mexico power tools and car parts/sensors to no longer buy into the thought.
Old 03-04-2018, 08:40 AM
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Re: OK to upgrade fuel pump on otherwise stock car?

Originally Posted by Tibo
Counterfeits, as in they come in an AC Delco box and are sold by the dealership and major outlets?

I've used the AC Delco fuel pump from the Syclones/typhoons (on Dyno Dons suggestion at that!) and had no problems with them. Meanwhile the famed Holley/Walbro fuel pumps that everyone recommends have never lasted much longer than a year. Perhaps its a "your mileage may vary" issue.
Yep, same with AC Delco oil filters. The issue is how well does the purchasing company sit on the Chinese. If not all that much then that product is wide open to being counterfeited. Case in point was a US company that sent some of their blower systems (air moving handlers), to China for production.

They were getting a lot of warranty returns and sent an engineer to spend some time with production. Needed to figure this out before they went bankrupt. After a couple of weeks the engineer returned and was speaking with the boss about his trip. Mentioned that due to the jet lag he was able to observe the 3rd shift first. Then the others as he acclimated to the time zone difference.

Boss immediately spoke up with a "what? We're only paying for two shifts."

The reason for the third shift was that the quality control was so bad that they needed it to produce enough good units to ship directly back to the purchasing company. The ones that failed quality control the Chinese sold on the gray market. Boom, tons of warranty claims.

RBob.
Old 03-04-2018, 03:55 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

Bogus AC Delco parts have been a problem for DECADES. There were memo's about this back in the '90s. This is NOT a new issue. Buying from a dealer or approved vendor should be OK, because GM can control that supply chain. Beyond that, it's hard to know for sure what you are getting. "Bargains" on parts on eBay and Amazon are always worrisome.

http://www.acdelco.com/counterfeit-auto-parts.html

It's really worse than described here. The counterfeit packaging is often so close, that the difference may be in the wording of a small line of legal script. The colors, font, and feel of the packaging is often nearly identical. But the part inside is not. Problem is, aside from the AC Delco box, how can you tell a real AC Delco pump from a counterfeit?

While AC Delco may be a bigger target, don't kid yourself that Bosch and other major global manufacturers don't have the same issue.

I have a friend (electrical engineer) who works for a prominent gas pump manufacturer. They would send the specs for circuit boards to a plant in China, get test parts back, all was good. Then in production, the plant would sneak back the quality of numerous components, leading to high failure rates in the field here. Production had to be moved again to get the quality they needed on a constant basis. Stories like these are endless.

Last edited by DynoDave43; 03-04-2018 at 04:03 PM.
Old 07-10-2018, 04:01 PM
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Re: OK to upgrade fuel pump on otherwise stock car?

My Delco I just installed from autozone was stamped Brazil
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