Dual In-Tank Pump System, G7X Turbo Buick, G-Body 1050LPH

1. Is the Hobbs pressure switch included with the DP system?

A 15 PSI Hobbs pressure switch and interface harness are included with the system as standard equipment. 15 PSI is the best pressure at which to activate the secondary fuel pump in most Turbo Buicks. Ideally the secondary pump should be activated approximately 100 HP shy of the primary pump running out of fuel to prevent pressure spikes or lean conditions. We recommend using either your computer or our Hobbs switch to control the secondary pump. This reduces the electrical load, fuel heating and wear on the secondary pump.

2. Can other pumps be used in the DP sender as an option?

This hanger can accommodate any 38mm body pump such as a 255, 340, 450 or 525 LPH pump in single or dual configuration. The DPFS-G71050 is our top-of-the-line, highest-flow DP system and is supplied exclusively with 2 x Walbro F90000285 (525 LPH) pumps. NOTE: WE DO NOT ACCEPT CUSTOMER-SUPPLIED PUMPS TO BE INCORPORATED INTO OUR DP SYSTEM PERIOD!

3. Is this DP system E85 compatible?

The DPFS-G71050 DP hanger uses Walbro F90000285 pumps which are 100% Ethanol compatible. Fuel system health will impact pump life.

4. Can I buy the entire DP system in a D-I-Y format?

We DO NOT offer this item as a D-I-Y kit.

5. I already have some other pumps. Can I use them with your system?

NOTE: ALL DP SYSTEMS ARE SOLD AS COMPLETE TESTED SYSTEMS. WE DO NOT ACCEPT CUSTOMER-SUPPLIED PUMPS.

6. I have a digital dash car. Do you have a 120-ohm level sensor for me?

Yes, please specify the digital dash level sender option when ordering your system.

7. What size of fuel lines do you recommend with this system?

For most users, our FLK-G7B5 (-8 PTFE feed / -6 PTFE return) is the ideal balance of performance and ease of installation. Even with -8 lines, this 1050 system provides significantly more flow than the 900 model. Only builds operating on the extreme edge (max effort E85) should consider a -10 PTFE feed line.

8. Where is the biggest restriction in the fuel system?

The factory steel lines running up the front of the motor.

9. Can I use a volt-booster with your system?

Yes, we recommend an alternator voltage booster. Increasing charging system voltage benefits pump performance under WOT, and all of our DP systems (and even factory pumps) benefit from it. We do not recommend inline pump voltage boosters such as the Kenne Bell Boost-A-Pump.

10. What brand of fuel pressure regulator do you recommend?

Racetronix REG-G7B1 (factory location / side port) or Racetronix REG-FI886BS universal with aftermarket rails.

11. Where do I get support and installation information?

This system is sold exclusively through our authorized dealer network. First-tier technical and warranty support, including all phone and email support, is provided by the authorized Racetronix dealer from which you purchased your system. Your dealer knows your vehicle and application and is your primary point of contact. Racetronix also maintains a technical support forum; however, we will always ask whether you have contacted your dealer first.

12. What are the performance specs of the DP system?

Typical test bench specs with 2 x F90000285 pumps:

13. How much HP will this system support in a Turbo Buick?

Multiply HP by 0.42 for fuel in LPH with a 20% safety margin. Use the flow data above to confirm output at your maximum boost pressure. Note that line restriction must be factored in; for maximum stability at extreme HP, a -10 feed line is necessary.

14. Are there higher flowing pumps that I can substitute?

The Walbro 525 (Hellcat) pumps are the highest-flowing pumps available for this modular hanger.

15. I already have an older line kit. Can I use it with this new DPFS module?

Older kits with 45° JIC fittings are not compatible. Adapt them by replacing heads with straight male ORBs: FIT-680706 (-6) or FIT-680708 (-8).

16. Do I need a -10 PTFE feed line to maximize performance?

Yes, to unlock the final 150-200 HP of headroom. However, routing a -10 line is a custom technical task, as there is no simple route through the factory frame rails.

17. Do you offer a pre-assembled -10 fuel line kit?

Not currently. Custom routing is required, including passage through the seat frame brace elliptical hole. We offer all necessary components for those with the technical capability to assemble their own -10 system.

18. What fittings and materials are recommended for custom line builds?

For maximum flow, use direct ORB straight hose fittings. These screw directly into the hanger and maintain a full-bore flow path without the restriction of a JIC flare:

• -10 Feed Fitting: FIT-680710 (Direct -10 ORB to -10 PTFE Hose)
• -8 Feed Fitting: FIT-P8RM10 (Direct -10 ORB to -8 PTFE Hose)
• -6 Return Fitting: FIT-680706 (Direct -6 ORB to -6 PTFE Hose)
• High-Quality Hose (-10): TFT-1170-10B (Static-dissipative PTFE with Hytrel® coating)
• High-Quality Hose (-8): TFT-1170-08B (Static-dissipative PTFE with Hytrel® coating)
• High-Quality Hose (-6): TFT-1170-06B (Static-dissipative PTFE with Hytrel® coating)

Rail Plumbing: Whether using the side-port REG-G7B1 or universal REG-FI886BS, several routing methods are valid. The critical factor for high-flow stability is a high-quality crossover line to ensure pressure balance between the rails.