Is the stock pump junk or is it just not well suited for high horse power use? I am referring to its ability to supply enough fuel to a modified engine not its quality of construction At what point does an aftermarket high volume pump become a requirement on a NA engine?

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92Z28
89GTA

 

They're marginal after 20K miles use with a stock engine.

 

Stock pumps are only rated at 50 psi and alot of us run right up next to that.
From what I hear they do seem to keep the psi up until they die. But since you have to drop the tank to replace just run it until it dies then replace. Mine blew at about 65,000 miles. Went out to start my car and did not hear the usual buzz I hear when I turned the key.

 

Any stock TPI pump is junk by now...do the math, they quit selling TPI cars in 92 so you have a nearly 10 year-old pump at best. It's pretty tired by now.

If you meant to ask if Delco replacement pumps are junk, I'd say no. There are better ones out there, but the Delco pumps are just fine for stock or mildly-modified replacement.

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1982 Z-28

See http://www.mycar.net/mafb/registry/detail.cfm?id=276 for details

 

I would be going with a Walbro pump if I decide to switch. What is this stuff about some cars having a "weak" pump? Is it due to low voltage to the pump?

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92Z28
89GTA

 

the stock TPI fuel pump will work for me on the ZZ4?

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1989 Chevrolet Camaro IROC-Z
L98 - 350c.i. TPI, rebuilt 700R4 auto w/shift kit, Dual catalyst Monza PaceSetter Cat-Back, SLP 1 5/8 Coated Headers, 3.23 Posi rear, Hypertech chip with 160stat, MSD 6A, Under-Drive pulleys, AFPR, K&N's, !Air Box w/ Ram Air, moddified MAF, !TB Coolant, Spohn Dual Cat SubFrame Connectors, Alarm, Keyless entry, remote starter, 92 Z28 AeroWing, Brand New Paint (6/21/01)

Future: ZZ4 TPI w/EGR, T56, 3.42 or 3.73, Spohn strut tower brace and LCA's

1989 Chevrolet Celebrity Eurosport
2.8 MPFI, no mods
225,000 miles and still ticking!

More info and pics on my webpage:http://go.to/iroc-z

AOL IMer: GPA 0point0

 

Let's see. There are about eleventy-jillion ThirdGens out there. Many of them have TPI, and many of those are modified at least a little. Less than half of them have had a fuel pump failure, and the median age of the fleet is somewhere around 13 years. There must be trillions of ThirdGen miles accumulated over the years.

So if over half of the original pumps are still working after thirteen years and a few million trips around the earth, yeah, they're probably no good. That's probably why you get the same design pump on a brand new LS6/Z06 'Y' car. GM likes to install "bad design" parts in their cars... especially the high performance ones.

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Later,
Vader
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"Click - Click - BOOM!"
Adobe Acrobat Reader

 

I was not questioning their quality. I was questioning their use in a modified car.

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92Z28
89GTA