B&M COMMANDFLO, BLUE User Manual

Installation Instructions

CommandFlo

Fuel Flow Modifier

1988-00 Honda Civic/CRX

1990-00 Acura Integra/NSX

The B&M CommandFlo Fuel Flow Modifier has been designed to work on all 1988 thru 2000 Honda Civics/ CRX's and 1990 thru 2000 Acura Integras/NSX's, except those models with TBI (Throttle Body Injection). The B&M CommandFlo Fuel Flow Modifier allows the user to accurately adjust fuel flow (and hence fuel pressure) in response to engine modifications. Most factory computers will compensate for minor airflow modifications (low restriction intake and exhaust) at part throttle operations but have no way to adjust at WOT (Wide Open Throttle). The results are a lean mixture right where you need more fuel! One way to correct this is to adjust fuel flow via fuel pressure. Most people don't understand that by increasing fuel pressure (on a fuel injection system), fuel flow increases. The formula for calculating flow increase based on fuel pressure is:

F1 = Injector Flow (cc/min) P1 = Current Fuel Pressure (psi) F2 = New Injector Flow (cc/min) P2 = New Fuel Pressure (psi)

P2 = P1 x

Example:

( )

We added a high flow exhaust that increases airflow 5%. What pressure should the system be set to?

F1 = 270 cc/min F2 = 284 cc/min (270 + 5%) P1 = 43 psi

P2 = 43 psi x or

P2 = 48 psi

We recommend that you read through the instructions completely before beginning the installation, so you can familiarize yourself with the installation procedure and tools required. Check the tool list at the end of these instructions for the tools required to install your B&M

CommandFlo Fuel Flow Modifier.

Installation of the CommandFlo Fuel Flow Modifier can be accomplished by anyone with minimum mechanical experience. It is however, important to closely follow the instructions. When installing your CommandFlo Fuel Flow Modifier there are several other B&M products you may wish to consider: B&M Fuel Pressure Gauge Set: #46053 or #46054. In order to take full advantage of the adjustability of the CommandFlo

284

( )

270

Fuel Flow Modifier, it is important to know the exact fuel pressure of your system. #46053 also includes adapt- ers for various import and domestic applications.

INTRODUCTION

The B&M CommandFlo Fuel Flow Modifier can be installed in less

than an hour by carefully following the instructions. Read all instruc-

tions first to familiarize yourself with the parts and procedures. This kit contains all parts

necessary to install the fuel flow modifier on all Honda Civics/CRX's and Acura Integras/NSX's.

DISASSEMBLY

We suggest the vehicle be allowed to cool for an hour or two before you begin since you will be working around the fuel system.

CAUTION: THE FUEL SYSTEM CONTAINS FUEL UNDER HIGH PRESSURE EVEN WHEN THE ENGINE IS NOT RUNNING. BEFORE DISCONNECTING A FUEL LINE, WRAP THE FITTING WITH A RAG TO PREVENT FUEL SPRAY.

Printed in the U.S.A.

9500645-04

STEP 1. Remove the fuel pump fuse from the fuse box. Try starting the vehicle several times until it will not remain running. This will help relieve pressure in the fuel system. Remove the plug and washer on the top of the fuel filter and attach an accurate pressure gauge. Remove and plug the vacuum line running to the fuel pressure regulator. Replace the fuse and start the vehicle. Note fuel pressure. STEP 2. Again, remove the fuel pump fuse from the fuse box. Try starting the vehicle several times until it will not remain running. This will help relieve pressure in the fuel system. Remove the negative battery cable. STEP 3. Using a pair of pliers, loosen the clamp holding the return fuel line to the fuel pressure regulator. Place a rag over the connection and carefully slide the fuel line off of the regulator. STEP 4. Using a 10mm socket and short extension, remove the two bolts holding the stock regulator to the fuel rail. Remove the regulator. Be careful of spraying

fuel!

STEP 5. Remove and inspect the regulator o-ring for tears. Replace if damaged. STEP 6. Carefully mount the regulator body in a vise and mark 1/4" down on the regulator "hat." Using a hacksaw, cut off the top of the regulator hat at the mark. Be care- ful: the top is under pressure from the spring inside! Remove and discard the top and spring (see fig.

1). STEP 7. Using a file, remove the sharp edges from the regulator.

ASSEMBLY

STEP 8. On the underside of the

new CommandFlo body, carefully insert the supplied silicone o-ring into the machined groove. STEP 9. Again, from the underside thread the brass piston into the CommandFlo body until it bot- toms out. Thread the supplied stainless steel nut onto the brass piston but do not tighten. STEP 10. Position the supplied spring into the CommandFlo body, making sure to seat it on the

brass piston. Without dropping the spring, install the CommandFlo body onto the stock pressure regulator. Place a drop of Locktite® on each of the four supplied 6-32 bolts and carefully attached the CommandFlo base (use caution when installing the screws to avoid stripping out the base). Once the base is attached, align the CommandFlo assembly as shown (see fig. 1). STEP 11. Hand tighten each of the four bolts until the base and body come together. DO NOT OVER TIGHTEN! STEP 12. Reinstall the stock regulator o-ring and attach the assembly the fuel rail. Using the 10mm socket, tighten the two bolts to 6 lb-ft. STEP 13. Slip the return fuel line back onto the regulator and retighten the clamp. STEP 14. Reinstall the fuel pump fuse and negative battery cable. STEP 15. Turn the key to on but do not start vehicle. Repeat this three times. Check the regulator for leaking fuel. If there is evidence of a leak, repair before proceeding. NOTE: The CommandFlo does not directly connect to the fuel side and thus will not cause the regulator to leak. STEP 16. Start the vehicle and using a 3/16" wrench, adjust the fuel pressure to the desired value based on the pressure measured before disassembly. Turning the piston clockwise will raise pressure while counterclockwise will lower pressure. Once the pressure

CommandFlo base

Stock regulator

O-ring

body

Align CommandFlo body as shown

Figure 1

is set, tighten the jam nut. STEP 17. Remove the factory vacuum line and replace it with the longer supplied line. Cut to fit if necessary. STEP 18. For nonpermanent type gauge sets, remove the fuel pump fuse from the fuse box. Try starting the vehicle several times until it will not remain running. This will help relieve pressure in the fuel system. Remove the fuel pressure gauge and reinstall the plug and washer on the top of the fuel filter. Replace fuel pump fuse. STEP 19. Verify that there are no signs of fuel leakage.

Parts List

1 CommandFlo Body 1 CommandFlo Base 1 Brass Piston 1 Spring 1 Silicone o-ring 4 6-32 Bolts 1 Jam Nut 1 Vacuum Line 1 Tube of Locktite® 1 Instruction Sheet

Tool List

Fuel Pressure Guage 10mm Socket and Drive 3/16", 1/2" Wrench Pliers Hacksaw 7/64" Hex Wrench Rags

Discard this

1/4"

section

6-32 bolts

Jam nut

Spring

Piston

CommandFlo body