LS3 Fuel Pressure - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

morepowerjoe · 02-05-2023, 05:35 PM

Hey guys I have a question. What's supposed to be the least amount of fuel pressure our engines have at wot? Because mine is 50 psi is that too low? It's only at wot. Thanks

Joseph

CamaroCracka · 02-06-2023, 05:34 AM

You're always supposed to have 58 psi at the rail, more if you are running forced induction. Sounds like you are running out of fuel pump.

morepowerjoe · 02-06-2023, 05:58 AM

In that case is there anyone that knows what's involved in replacing the pump with a ZL1 pump besides the installation itself. Cause I think I can install it with no problem I just don't know what to about the fpcm and tuning.

Badbubba · 02-06-2023, 06:27 AM

My 2010, factory pump and injectors, will go to the low 50s and have a hard time recovering. That's when I was logging with an SCT for ARH 1 7/8" long tubes and CAI box. At probably around 10-13k miles on the odometer. It dropped into the mid and upper 40s when I was pulling from the fuel rail for a small shot of N2O. I didn't like that, so I installed a dedicated fuel tank for the N2O. My afr was still fine though, either way. What was your baseline fuel pressure from previous logs?

morepowerjoe · 02-06-2023, 08:39 AM

Quote:

Originally Posted by Badbubba

My 2010, factory pump and injectors, will go to the low 50s and have a hard time recovering. That's when I was logging with an SCT for ARH 1 7/8" long tubes and CAI box. At probably around 10-13k miles on the odometer. It dropped into the mid and upper 40s when I was pulling from the fuel rail for a small shot of N2O. I didn't like that, so I installed a dedicated fuel tank for the N2O. My afr was still fine though, either way. What was your baseline fuel pressure from previous logs?

It still went down to 50 psi but didn't pull timing like it did this time and another thing is I just installed a a/f ratio gauge and it actually went a little lean to 13.5. On another note a couple weeks ago I had my cats removed and a true x pipe put in the exhaust. Maybe a few extra hp maxed out the pump? Idk

Risingson05 · 02-06-2023, 09:55 AM

My base is 58psi but I have lsa - and fore system . Ive seen max psi at wot hit 75+ psi ..

How old is your pump ? Maybe it’s getting tired ?

morepowerjoe · 02-06-2023, 10:03 AM

Quote:

Originally Posted by Risingson05

My base is 58psi but I have lsa - and fore system . Ive seen max psi at wot hit 75+ psi ..

How old is your pump ? Maybe it’s getting tired ?

Pump is original with 170k miles.

1JEWLDSSRS · 02-06-2023, 10:06 AM

Quote:

Originally Posted by morepowerjoe

Pump is original with 170k miles.

Sounds like it's time for a pump joe!! My stock one took a dump around 95k, just before the cam swap, which we did at 98k and we replaced it with a ZL1 pump and no issues with it so far.

Risingson05 · 02-06-2023, 10:08 AM

Quote:

Originally Posted by morepowerjoe

Pump is original with 170k miles.

Sounds like a trap door mod and new pump is in the near future . Mine aswell as upgrade the pump once your there ..

morepowerjoe · 02-06-2023, 10:09 AM

Yeah that's what I'm thinking guys. Thanks

1JEWLDSSRS · 02-06-2023, 10:13 AM

Yes sir, welcome. And if you do the trap door thing, just make sure you don't do like one of the guys did and start cutting too deeply and in the incorrect spot and cut his wires and poked a hole in his tank!! There are a lot of vids on YT as to how to do it. Good luck. We dropped the tank on mine.

Badbubba · 02-06-2023, 10:47 AM

Quote:

Originally Posted by morepowerjoe

It still went down to 50 psi but didn't pull timing like it did this time and another thing is I just installed a a/f ratio gauge and it actually went a little lean to 13.5. On another note a couple weeks ago I had my cats removed and a true x pipe put in the exhaust. Maybe a few extra hp maxed out the pump? Idk

My cat material blew out and was restricting the exhaust flow. I kept having to lean out the tune because of it. After finding and correcting the restrictions, the tune needed to be richened up. Your cats may have been limiting flow. May just need to tweak the tune alittle. Now that your on the lean side, you may be getting knock and retarding the timing. Any knock on the log?

morepowerjoe · 02-06-2023, 10:50 AM

Quote:

Originally Posted by Badbubba

My cat material blew out and was restricting the exhaust flow. I kept having to lean out the tune because of it. After finding and correcting the restrictions, the tune needed to be richened up. Your cats may have been limiting flow. May just need to tweak the tune alittle. Now that your on the lean side, you may be getting knock and retarding the timing. Any knock on the log?

No sir no knock and no cats.

CamaroCracka · 02-06-2023, 12:57 PM

Quote:

Originally Posted by morepowerjoe

In that case is there anyone that knows what's involved in replacing the pump with a ZL1 pump besides the installation itself. Cause I think I can install it with no problem I just don't know what to about the fpcm and tuning.

You only need the modified fpcm if you are running forced induction. It allows the fpcm to compensate for boost.

A lot of guys do the trap door, but as long as the tank is close to empty I can drop the tank, change the pump and put it back up in 2-3 hours. You just lower the front end of the cradle, disconnect the power and the lines, and remove two bolts with a jack under the tank. The higher you get the rear of the car, the easier it will be.

02-05-2023, 05:35 PM	#1
morepowerjoe Drives: 2012 Chevrolet Camaro l99 Join Date: Aug 2020 Location: Austin, TX Posts: 2,105	LS3 Fuel Pressure Hey guys I have a question. What's supposed to be the least amount of fuel pressure our engines have at wot? Because mine is 50 psi is that too low? It's only at wot. Thanks Joseph __________________ DSS FX Forged Pistons, Eagle ESP L19 Forged Rods, ARP Head and Main Studs, TSP PRC 260 CNC Ported Heads milled .030, Cometic .040 Head Gaskets, GPI SS3 VVT Camshaft, GM Performance Racing Lifters, CHE Trunnions , Molly Pushrods, Melling 10355HV Oil Pump, Cold Air Inductions CAI, Fast LSXR Intake Manifold, Nick Williams 103 TB, TSP 1 7/8" Longtubes with 3" TSP Exhaust, ZL1 Fuel Pump, Mishimoto Radiator, Mishimoto Oil Cooler, Tru Cool 40k Tranny Cooler, 3600 Circle D Converter, Fluid Dynamics Balancer Build Thread https://www.camaro5.com/forums/showthread.php?t=609817

02-06-2023, 05:34 AM	#2
CamaroCracka Drives: 2010 Turbo LS3 Join Date: Dec 2009 Location: Palm Bay, FL Posts: 2,736	You're always supposed to have 58 psi at the rail, more if you are running forced induction. Sounds like you are running out of fuel pump. __________________ 2010 SS - On3 kit with downpipe cutout, CTR 78/80, CompCam 239/251 620/632 122+4, E85, Z28 suspension and ZL1 diff with Outlaw axles. Gen6 ZL1/1LE brakes. 2011 Vert - 416/w 230/236 .612/.602 115lsa, 1LE suspension w/32mm rear bar. Z28 diff. ZL1 brakes.

02-06-2023, 05:58 AM	#3
morepowerjoe Drives: 2012 Chevrolet Camaro l99 Join Date: Aug 2020 Location: Austin, TX Posts: 2,105	In that case is there anyone that knows what's involved in replacing the pump with a ZL1 pump besides the installation itself. Cause I think I can install it with no problem I just don't know what to about the fpcm and tuning. __________________ DSS FX Forged Pistons, Eagle ESP L19 Forged Rods, ARP Head and Main Studs, TSP PRC 260 CNC Ported Heads milled .030, Cometic .040 Head Gaskets, GPI SS3 VVT Camshaft, GM Performance Racing Lifters, CHE Trunnions , Molly Pushrods, Melling 10355HV Oil Pump, Cold Air Inductions CAI, Fast LSXR Intake Manifold, Nick Williams 103 TB, TSP 1 7/8" Longtubes with 3" TSP Exhaust, ZL1 Fuel Pump, Mishimoto Radiator, Mishimoto Oil Cooler, Tru Cool 40k Tranny Cooler, 3600 Circle D Converter, Fluid Dynamics Balancer Build Thread https://www.camaro5.com/forums/showthread.php?t=609817

02-06-2023, 06:27 AM	#4
Badbubba GrINned & JUICEd Drives: 15STI, 10Expy, 10 2SS/RS M6, 47KB1 Join Date: Nov 2009 Location: Pittsburgh, PA Posts: 1,247	My 2010, factory pump and injectors, will go to the low 50s and have a hard time recovering. That's when I was logging with an SCT for ARH 1 7/8" long tubes and CAI box. At probably around 10-13k miles on the odometer. It dropped into the mid and upper 40s when I was pulling from the fuel rail for a small shot of N2O. I didn't like that, so I installed a dedicated fuel tank for the N2O. My afr was still fine though, either way. What was your baseline fuel pressure from previous logs? __________________ GPI SS3 Cam & stuff,N.O. Plate(dedicated fuel tank,progressive,fuel hose upgrade,remote opener,heater,console switches),LNC2000,CTAP,ARH 1 7/8" LTs/gutted cats/X pipe/mufflers,Jet Hot coated LTs,GPI HPT Tune,CAI, Scoop,Rx Catch Can,Gates heater hose relocation, Remote clutch & auto brake res,Metco loop,Momentum Tunnel Brace,TSW Nurb 18",555 & 05,Pfadt trailing arms & toe rods,Autometer WB,Fesler Pillar Pod,LED strips (int),Lloyds floor & trunk mats,LED DRL/front turn & license plate,DRL harness,VLEDs tail lights,Plasticoat Bowties. Ord: Oct 5, 2009 Rec: Nov 19, 2009 13.17@112.6 stock

02-06-2023, 09:55 AM	#6
Risingson05 Drives: 2015 zl1 m6 Join Date: Jan 2020 Location: Alaska Posts: 702	My base is 58psi but I have lsa - and fore system . Ive seen max psi at wot hit 75+ psi .. How old is your pump ? Maybe it’s getting tired ? __________________ 791whp 699 ft lbs torque on E30 - ported sc /heads by boost mode racing - PAT G cam /Tune PB:10.7 @133.9

02-06-2023, 10:09 AM	#10
morepowerjoe Drives: 2012 Chevrolet Camaro l99 Join Date: Aug 2020 Location: Austin, TX Posts: 2,105	Yeah that's what I'm thinking guys. Thanks __________________ DSS FX Forged Pistons, Eagle ESP L19 Forged Rods, ARP Head and Main Studs, TSP PRC 260 CNC Ported Heads milled .030, Cometic .040 Head Gaskets, GPI SS3 VVT Camshaft, GM Performance Racing Lifters, CHE Trunnions , Molly Pushrods, Melling 10355HV Oil Pump, Cold Air Inductions CAI, Fast LSXR Intake Manifold, Nick Williams 103 TB, TSP 1 7/8" Longtubes with 3" TSP Exhaust, ZL1 Fuel Pump, Mishimoto Radiator, Mishimoto Oil Cooler, Tru Cool 40k Tranny Cooler, 3600 Circle D Converter, Fluid Dynamics Balancer Build Thread https://www.camaro5.com/forums/showthread.php?t=609817

02-06-2023, 10:13 AM	#11
1JEWLDSSRS Drives: 2011 SS-RS Join Date: May 2011 Location: FLORIDA Posts: 11,435	Yes sir, welcome. And if you do the trap door thing, just make sure you don't do like one of the guys did and start cutting too deeply and in the incorrect spot and cut his wires and poked a hole in his tank!! There are a lot of vids on YT as to how to do it. Good luck. We dropped the tank on mine. __________________ TSP STAGE 3 CAM,231/246 @112 LSA 614/641 LIFT, CIRCLE D 5C-4200-4500 CONVERTER,LOD INTAKE.CORSA EXHAUST. DSS 1 PC DS. PEGASUS SOLID CRADLE MOUNTS. 486RWHP/475RWTQ.LOTS MORE.