Dual In-Tank Pump System, G7X Turbo Buick, G-Body 550LPH
Dual In-Tank Pump System, G7X Turbo Buick, G-Body 550LPH
PART NUMBER: DPFS-G7550
550 LPH E100 Dual In-Tank Fuel System, 1984-87 Turbo Buick
Engineered for the Turbo Buick enthusiast who demands uncompromising reliability without the extreme current draw of a "max-effort" setup, the Racetronix DPFS-G7550 is the definitive 550 LPH fueling solution. This system incorporates our patented Pump Stacking technology, utilizing a modular "ship-in-a-bottle" design that allows high-flow pumps to be inserted individually and interlocked inside the tank. This innovation overcomes the physical limitations of factory tank openings, enabling high fueling capacity without permanent tank modifications. Unique to the 550 system, the staged pump logic allows for sleeper builds and phased restorations where the use of factory fuel lines may be required.
Features
- CNC Billet T6 Aluminum Modular Dual Fuel Pump Hanger
- Patented "Pump Stacking" Modular Design for easy installation
- 2 x Racetronix RXP-255E2 255 LPH E85 Fuel Pumps
- Weatherproof 100% plug & play heavy-duty wiring harness
- Massive -10 AN ORB outlet, -6 AN ORB return ports
- Dedicated pump circuits with new 6-way bulkhead connector
- Includes a new stainless-steel locking ring, OE-type tank gasket
- 90 ohm ceramic level sender resistor (analog dash - standard)
- 120 ohm ceramic level sender resistor (digital dash - optional)
- Multiple optional feed & return port configurations
*SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
Fuel System Plumbing Options
For maximum performance, a -8 PTFE feed line and -6 PTFE return line are highly recommended (See Racetronix FLK-G7B5).
Factory Line Compatibility
Unlike higher-flow models, the DPFS-G7550 can conceivably be used with factory fuel lines. Because the pumps are staged, a single primary pump will not overwhelm the factory regulator/return at idle or cruise. Under boost, the motor's consumption offsets the flow when the second pump activates.
Note: Using factory lines will restrict total performance. Use of specific barb-to-ORB adapters is required (See Technical Q&A #8 for part numbers).
HD Harness Features
- Plug & Play (no cutting or splicing required)
- Weatherproof factory connectors
- Heavy-gauge automotive-grade copper wire on main power feeds and intermediate harness
- Heavy-duty weatherproof 630-series relays mount behind fuel tank (no under-hood clutter)
- Weatherproof 630-series dual fuse holder with stainless bracket (mounts on back of alternator)
- Pump power indicator lamp outputs
- Swap-able primary / secondary pump ground control connectors
- Alternator-direct power for maximum pump performance
- Silicone grease, spare fuse, wire ties included
- Stainless steel mounting hardware
- 15 PSI Hobbs pressure standard switch with interface harness (optional 4, 7 and 10 PSI)
- Body ground upgrade with battery nuts (included)
* This DPWH-G77HD DP harness is an upgraded version of our FPWH-021HD harness only sold with our new 500/700/900/1050 DP senders.
Projected Horsepower Support
The DPFS-G7550 configuration is engineered to provide substantial fueling overhead while maintaining high efficiency. When utilizing standard gasoline, this system is projected to support upwards of 750 RWHP. For users running E85/Ethanol blends, the system is projected to support upwards of 550 HP. These figures assume the use of properly sized fuel lines. If utilizing factory fuel lines, these projections will be reduced due to the restrictive nature of the OE plumbing and filter.
Applications
| Year | Model | Sub | Eng. | Liter | Fuel | F.Del | Asp. | VIN |
|---|---|---|---|---|---|---|---|---|
| 1987 | REGAL | GRAND NATIONAL | V6 | 3.8 | GAS | FI | T | 7 |
| 1987 | REGAL | GNX | V6 | 3.8 | GAS | FI | T | 7 |
| 1987 | REGAL | LIMITED | V6 | 3.8 | GAS | FI | T | 7 |
| 1986 | REGAL | GRAND NATIONAL | V6 | 3.8 | GAS | FI | T | 7 |
| 1986 | REGAL | T-TYPE | V6 | 3.8 | GAS | FI | T | 7 |
| 1985 | REGAL | GRAND NATIONAL | V6 | 3.8 | GAS | FI | T | 9 |
| 1985 | REGAL | T-TYPE | V6 | 3.8 | GAS | FI | T | 9 |
| 1984 | REGAL | GRAND NATIONAL | V6 | 3.8 | GAS | FI | T | 9 |
| 1984 | REGAL | T-TYPE | V6 | 3.8 | GAS | FI | T | 9 |
Technical Q&A
1. Is the Hobbs pressure switch included?
Yes, a 15 PSI Hobbs pressure switch and interface harness are included to activate the secondary pump during boost.
2. Can other pumps be used in this sender?
This modular hanger can accommodate 255, 340, 450, or 525 LPH pumps. The DPFS-G7550 is supplied exclusively with 2 x Racetronix RXP-255E2 (255 LPH) pumps. NOTE: WE DO NOT ACCEPT CUSTOMER-SUPPLIED PUMPS.
3. Is this system E85 compatible?
Yes, the RXP-255E2 pumps are 100% Ethanol compatible.
4. What are the performance specs?
Typical test bench specs for 2 x RXP-255E2 pumps:
| Flow | Pressure | Voltage | Current |
|---|---|---|---|
| 540 LPH | 43.5 psi | 14.0 v | 18.0 A |
| 640 LPH | 43.5 psi | 16.0 v | 22.0 A |
| 420 LPH | 80.0 psi | 14.0 v | 24.0 A |
| 510 LPH | 80.0 psi | 16.0 v | 28.0 A |
5. Can I use this system with factory fuel lines?
Yes. The G7550 is unique because its staged 255 LPH pumps allow the primary pump to run at cruise/idle without overwhelming the factory regulator. Once boost activates the second pump, the engine's consumption prevents backpressure issues. However, the factory lines remain a restriction that will limit the system's absolute power potential.
6. 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.
7. 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.
8. What fittings do I need to connect this hanger to my fuel lines?
For a Plug-and-Play high-performance setup, we recommend our FLK-G7B5 PTFE kit.
If adapting to factory lines using hose barbs, the following adapters are required:
- Return Port: ADF-HB56RM6 (5/16" Barb to -6 ORB Male).
- Feed Port (2-Part Assembly): First, install the reducer ADF-RF0810 (-8 ORB Female to -10 ORB Male), then install the barb adapter ADF-HB38RM8 (3/8" Barb to -8 ORB Male).
For Custom AN setups, use ORB-to-JIC adapters: ADF-495104 (Feed) and ADF-495100 (Return).
© 2026 Racetronix. All Rights Reserved. | Part No: DPFS-G7550 | Revision: Bravo
