JMS, MSD, or no fuel pump voltage booster

[turbofiveoh]

When I got my whipple kit I got an MSD fuel pump voltage booster with it. I'm not a big fan of fuel pump voltage boosters so I installed a DW400 and called it a day. After reading about some of the fueling issues others are having I'm revisiting my decision. I haven't pulled logs but based on what others are experiencing I wouldn't be surprised if my combination is suffering from flow rate decay at high loads and would rather be safe than sorry.

After doing some searching I see most people are using JMS boosters. I don't see many people using MSD products and Whipple no longer offers the MSD booster on their website. Does it make sense to install the MSD I have or get a JMS. I have no interest in installing a return style system as this will always be a low boost, pump gas combination. If there's a proven reliable product out there I'll buy it.

Setup is a stage 2 gen 3 Whipple on a gen 2 engine with Kooks 1-7/8" long tubes. 91 octane, 3.750 upper, stock diameter lower, and factory whipple calibration.

Thanks for the recommendations.

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[engineermike]

3.75 pulley on gasoline is most probably fine with just the dw400. If you can mod the tune, I can show you how to send 15.2 volts to it at high fuel demand times.

 

[NGOT8R]

The JMS is nice, in that it doesn’t run continuously (only when a certain throttle percentage is reached). I believe Deatschwerks recommends setting voltage at 18V, rather than 22V. I’ve been running mine for over 3 1/2 years now without issue, both naturally aspirated and with nitrous.

 

[turbofiveoh]

3.75 pulley on gasoline is most probably fine with just the dw400. If you can mod the tune, I can show you how to send 15.2 volts to it at high fuel demand times.

I am comfortable modding the tune, I just need to decide on an interface.

Based on your recommendation in another thread I had started looking at the pcmtec product. I have a MPVI3 somewhere in my toolbox so I would just need to find it and purchase 2 licenses for it. However, given your preference with pcmtec I'm thinking about buying one and learning the software.

In either case, I'd happily take you up on your offer to adjust the fuel pump voltage (presumably through the FPDM) versus adding another piece of electronics to the car.

Thanks!

 

[turbofiveoh]

The JMS is nice, in that it doesn’t run continuously (only when a certain throttle percentage is reached). I believe Deatschwerks recommends setting voltage at 18V, rather than 22V. I’ve been running mine for over 3 1/2 years now without issue, both naturally aspirated and with nitrous.

The MSD works in a similar way, not based on TPS rather on MAP. MSDView has a user configurable Pump Voltage vs MAP table. I am assuming the MSD box behaves the same way the JMS box does when low voltage is commanded.

It is encouraging to know that your DW400 has been paired with a JMS box and running reliably for nearly 4 years. Assuming the car is driven on a regular basis that says a lot about the quality of the hardware.

 

[NGOT8R]

The MSD works in a similar way, not based on TPS rather on MAP. MSDView has a user configurable Pump Voltage vs MAP table. I am assuming the MSD box behaves the same way the JMS box does when low voltage is commanded.

It is encouraging to know that your DW400 has been paired with a JMS box and running reliably for nearly 4 years. Assuming the car is driven on a regular basis that says a lot about the quality of the hardware.

I installed the DW400 for about 7-8 months, after I had a factory fuel pump fail at 7K miles. Since then I’ve only put 1500 miles on the car. However, the JMS has been on the car ever since 472 miles on the odometer.

 

[engineermike]

If you ever plan on doing flex tuning, then I would suggest PCMtec because hpt hides some important parameters needed for flex.

 

[turbofiveoh]

If you ever plan on doing flex tuning, then I would suggest PCMtec because hpt hides some important parameters needed for flex.

I don't have any desire to run flex fuel but it is a nice option to have should things change. PCMtec looks to be a much better option. The PCM write time alone makes it the desirable choice.

Do you use a J2534 interface cable or something else?

 

[HKusp]

If you get the PCMTec software and license, I believe they give you a code with a discount on the OBDX Pro FT - Ford OBD2 J2534.

 

[turbofiveoh]

If you get the PCMTec software and license, I believe they give you a code with a discount on the OBDX Pro FT - Ford OBD2 J2534.

Good to know...thank you.

 

[engineermike]

I don't have any desire to run flex fuel but it is a nice option to have should things change. PCMtec looks to be a much better option. The PCM write time alone makes it the desirable choice.

Do you use a J2534 interface cable or something else?

I’m using the Obx ft but my friend tried a Chinese Amazon $30 model and it worked as long as you destroy the virus laden installation software it came with.

 

[turbofiveoh]

For the price difference OBDX seems like a no brainer.

 

[tosha]

Anyone tried this one? https://www.obdlink.com/products/obdlink-mxp/
@engineermike , do you think it would work for PCMTec?

 

[engineermike]

In either case, I'd happily take you up on your offer to adjust the fuel pump voltage (presumably through the FPDM) versus adding another piece of electronics to the car.

Here's the short version:

This is the max voltage it will send to the pump. Stock is 12 ot 12.5. This will also prevent BAPs from using their full potential.

This is the max system voltage:

This is the command voltage at "high fuel flow":

These should be modified as you see fit with your own thresholds to get the behavior you want:

As always, it should be logged to make sure it's doing as intended. Some tuners run 15.2 volts all the time, which I believe shortens battery life. I haven't found a reason yet not to change this to where it only increases voltage during high fuel demand situations.

 

[engineermike]

Anyone tried this one? https://www.obdlink.com/products/obdlink-mxp/
@engineermike , do you think it would work for PCMTec?

I don't see J2534 listed on that page. I can only speak directly to the OBX FT because PCMTec recommends it and it's what I use. The cheap chinese one I can supply links and only say that my buddy tested it and found it works as long as you steer clear of their supplied software. All others, make sure it's J2534 and refer to PCMTec.

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