Looking for the flow rate on the Delco ep376 vs the stock GTP fuel pump.
Seems my 3800SC is having high rpm fuel issues. I have the 376 in it.

quote Originally posted by Odin: Looking for the flow rate on the Delco ep376 vs the stock GTP fuel pump. Seems my 3800SC is having high rpm fuel issues. I have the 376 in it.

Unless u r extremely heavily modded the 376 has ur swap covered. Unless u have an actual bad pump..

If your 3800SC is having high RPM fuel issues, it should be verified. The easiest way is with a wideband O2 sensor. You can buy portable units that clamp on to your exhaust pipe to take readings. That's what we use.
If the engine is confirmed as running lean, the next step is to monitor fuel pressure when it goes lean. IMO all boosted engines should run a fuel pressure gauge to check on how the supply is doing. If the pressure drops below about 40psi + boost its a defective pump or regulator. BTW do you have the proper Bosch 3 bar regulator on the fuel rail?

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[This message has been edited by Dennis LaGrua (edited 06-07-2014).]

I'm not sure about the flow rate, but was able to find a chart showing how much HP it can support at different pressure levels. Maybe this will help?

http://www.gmtuners.com/tech/fuel_pumps.htm

Also, it seems the EP376 wasn't intended to operate on more than 50psi fuel pressure.

The EP-376 pump was designed for N/A engines that never saw over 50psi of fuel pressure. One 3rd party flow test of an EP-376 pump suggested it might support up to about 288 crank hp @ 60 psi of fuel pressure. I've seen lower advertised flow rates elsewhere since.

In contrast, the EP-381 pump was designed for N/A and Turbocharged applications that did see over 50psi of fuel pressure. NAPA Online's provided flow test data for the Delphi equivalent pump to the Delco EP-381 suggested it would support up to 299hp @ 61 psi of fuel pressure.

Since the price of a new genuine AC Delco EP-381 pump is less than $60 from Amazon.com, I don't see why it is worth it to chance using an EP-376 with any boosted application.

I have purchased and installed numerous AC Delco EP-381 pumps I purchased from Amazon.com in countless 3800 Series 2 (and Series 3) SC swaps I've done in Fieros and other GM cars - and never had a problem with these pumps supplying enough fuel flow at the pressures that were asked of it in those particular applications (none of which produced over 300 crank hp). In contrast, I do know of a few people who have had problems with the EP-376 pumps over the years being able to keep up with stock or lightly modded 3800 SC engines.

That having been said, if you have an engine capable of making over 299 crank HP, you are going to need an aftermarket performance fuel pump.

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[This message has been edited by Darth Fiero (edited 06-10-2014).]

Thanks for the replies. Dennis, everything fuel related on my motor is stock 3800iisc except for the pump and lines. Darth, I know I should have probably put the 381 in instead, but the 376 is what I have until I drop the tank to replace the fuel level sending unit. Car is running fine except in high rpm range. Then I get what feels like retarded timing but my scanner shows 0kr. I am running a 3.5 pulley as well as 1.9 rockers with yellow valve springs. As well as a 3" exhaust with a very large cold air cone piped from the side intake with 3.5 pipe. Darth did my computer. I'm not throwing any codes. It's got new plugs and wires on it. I'm wondering if maybe the problem is ignition coil related or could have to do with fuel octane? Right now it has 91 in it. But other than that and fuel pressure I'm not sure where to look. Also thanks for the chart blacktree. Also has a brand new fuel filter on it.

quote Originally posted by Odin: Thanks for the replies. Dennis, everything fuel related on my motor is stock 3800iisc except for the pump and lines. Darth, I know I should have probably put the 381 in instead, but the 376 is what I have until I drop the tank to replace the fuel level sending unit. Car is running fine except in high rpm range. Then I get what feels like retarded timing but my scanner shows 0kr. I am running a 3.5 pulley as well as 1.9 rockers with yellow valve springs. As well as a 3" exhaust with a very large cold air cone piped from the side intake with 3.5 pipe. Darth did my computer. I'm not throwing any codes. It's got new plugs and wires on it. I'm wondering if maybe the problem is ignition coil related or could have to do with fuel octane? Right now it has 91 in it. But other than that and fuel pressure I'm not sure where to look. Also thanks for the chart blacktree. Also has a brand new fuel filter on it.

Odin, I'm sending you a PM asking more questions about your problem...