Wiring in a KB Boost a pump

[E85LSX]

Originally Posted by ADM PERFORMANCE

All you guys do understand that the ECM and FPCM control the fuel pressure.



Andy

I do.

I also read that the FPCM outputs a constant voltage but just regulates the pulse width of the signal to vary the speed of the pump. A member on the Hptuners forums mentioned this as he used a scope to see what the FPCM outputed. He also said the voltage was regulted to 12v out. This may also be the case here, although if this were the case the BAP would not work at all. . .

My guess here is that the FPCM is still altering the voltage out along with the pulse width of the signal which is why the BAP does not give the 50-75% more flow as it would on a car that does not have a returnless fuel system with a FPCM.

[ADM PERFORMANCE]

Originally Posted by E85LSX

I do.

I also read that the FPCM outputs a constant voltage but just regulates the pulse width of the signal to vary the speed of the pump. A member on the Hptuners forums mentioned this as he used a scope to see what the FPCM outputed. He also said the voltage was regulted to 12v out. This may also be the case here, although if this were the case the BAP would not work at all. . .

My guess here is that the FPCM is still altering the voltage out along with the pulse width of the signal which is why the BAP does not give the 50-75% more flow as it would on a car that does not have a returnless fuel system with a FPCM.

Do your self a favor and run 12volts from the battery to the fuel pump and see just how high the fuel pressure is.You might be suprised!

[E85LSX]

Originally Posted by ADM PERFORMANCE

Do your self a favor and run 12volts from the battery to the fuel pump and see just how high the fuel pressure is.You might be suprised!

I think I could maintain pressure better with 12-14volt directly to the pump, and if not than definitely with 17volt to the pump. . .

Have you tried this? Do you agree?

[R8cerX]

Originally Posted by ADM PERFORMANCE

Do your self a favor and run 12volts from the battery to the fuel pump and see just how high the fuel pressure is.You might be suprised!

Wouldn't running straight voltage to a pump that is supposed to be pulse modulated, just burn the pump up...quickly?

[R8cerX]

OK, have the car on the dyno right now. With the BAP wired before the FPCM, our datalog shows 48-50psi at 6100 RPM at 10lbs of boost- car made 517rwhp.

tried to add 5% fuel in the tune, then fuel pressure dropped to 45psi and car made 527rwhp.

The pump and BAP are at the limit in this L99.

Does anyone know if the LS3 and the L99 have the same fuel pump from the factory?

[Icon Autosports]

Originally Posted by E85LSX

Took me a while to figure this out. . . I'll post up a real good thread on how to do it and why this weekend after I get my setup finalized. Alot of people and shops are wiring them incorrectly with out knowing it and are assuming it works since the stock fuel system is so robust.

I am running E85 and have at least 450hp to the wheels. The e85 requires 30% more fuel than gas to make the same power. So the stock system could handle up to about 600rwhp with no modifications.

the trick with the BAP is that it needs to be wired after the Fuel Pump Control Module. . . the other trick is that it cant be triggered to turn on with less than 10v input.

Wiring the boost a pump in the trunk after the fuse to the FPCM does not work despite the fact that many are doing it this way. The FPCM varies its output voltage to the fuel pump based on the fuel demand regardless of its input voltage.

Again, I will post this weekend to make this very clear, I'll even include pics!

Thanks to those who helped me figure this out (Icon)

The Kenne Bell BAP wired AFTER the FPCM has been working on a customers' M6 SS that is daily driven and making over 700rwhp with the stock single fuel pump, stock lines, and F.A.S.T. 65lb injectors. Zero issues.

The BAP needs to be wired AFTER the FPCM. a Nitrous Outlet digital RPM activated window switch MUST BE USED or you will continue to blow the BAP in-line fuse because the BAP will continue to try to turn itself on using the low 6-7 volt input the FPCM is sending it at idle. Figure out where your boost comes in, what RPM the fuel pressure starts to drop under WOT, and set the window switch to TURN ON the BAP a few hundred RPM before that and the fuel pressure will never drop and you will no longer blow fuses. With this wired correctly, the BAP WILL NOT turn on under idle or normal driving conditions until you go WOT and the desired RPM is reached to turn on the BAP. You will see a rich "spike" in AFR while tuning but if whoever is tuning knows what they are doing, they can smooth this out.

Search "Icon Autosports" on YouTube and you will see the silver 2010 SS I am speaking of.

[E85LSX]

Originally Posted by Icon Autosports

The Kenne Bell BAP wired AFTER the FPCM has been working on a customers' M6 SS that is daily driven and making over 700rwhp with the stock single fuel pump, stock lines, and F.A.S.T. 65lb injectors. Zero issues.

The BAP needs to be wired AFTER the FPCM. a Nitrous Outlet digital RPM activated window switch MUST BE USED or you will continue to blow the BAP in-line fuse because the BAP will continue to try to turn itself on using the low 6-7 volt input the FPCM is sending it at idle. Figure out where your boost comes in, what RPM the fuel pressure starts to drop under WOT, and set the window switch to TURN ON the BAP a few hundred RPM before that and the fuel pressure will never drop and you will no longer blow fuses. With this wired correctly, the BAP WILL NOT turn on under idle or normal driving conditions until you go WOT and the desired RPM is reached to turn on the BAP. You will see a rich "spike" in AFR while tuning but if whoever is tuning knows what they are doing, they can smooth this out.

Search "Icon Autosports" on YouTube and you will see the silver 2010 SS I am speaking of.

Icon, I hope this setup continues to work with no problems because I would like to set mine up this way. When I wired my BAP after the FPCM I had it triggered on all the time, I did not try the window switch method you advised. . . Please keep us posted, Thanks

[acowherd]

Originally Posted by Icon Autosports

The Kenne Bell BAP wired AFTER the FPCM has been working on a customers' M6 SS that is daily driven and making over 700rwhp with the stock single fuel pump, stock lines, and F.A.S.T. 65lb injectors. Zero issues.

The BAP needs to be wired AFTER the FPCM. a Nitrous Outlet digital RPM activated window switch MUST BE USED or you will continue to blow the BAP in-line fuse because the BAP will continue to try to turn itself on using the low 6-7 volt input the FPCM is sending it at idle. Figure out where your boost comes in, what RPM the fuel pressure starts to drop under WOT, and set the window switch to TURN ON the BAP a few hundred RPM before that and the fuel pressure will never drop and you will no longer blow fuses. With this wired correctly, the BAP WILL NOT turn on under idle or normal driving conditions until you go WOT and the desired RPM is reached to turn on the BAP. You will see a rich "spike" in AFR while tuning but if whoever is tuning knows what they are doing, they can smooth this out.

Search "Icon Autosports" on YouTube and you will see the silver 2010 SS I am speaking of.

Waiting for an update.........

[BlownSS]

where is this wired in at? Is the FPCM in the trunk? Easy to get to?

[lock]

Where are you guys mounting the adjustmet knob? In the trunk? Guessing its only needed during tuning sessions.

[Jchaluja]

update?

[lock]

Originally Posted by Jchaluja

update?

Yeah alot of loose ends in this. would be cool to have a final solution for future installers like me.

[IConnection]

I gotta step in here, IF U WIRE THE BOP CORRECTLY IT WORKS PERFECTLY
(SET TO COME ON AT 5LBS OF BOOST)

We have seen voltage go up and fuel pressure stay ROCK SOLID at 625RW
Just like Icon said, We see a slight spike and then its perfect, we just tune for it.


In about 2 weeks we will see the limits of it, we have a car coming in for a smaller pulley (10lbs) and
85lbers along with a larger intercooler...

We have seen the vettes (Z06 PUMP/BOP) make right around 700RW before it was a problem..
I cant speak for the camaro fuel system yet, so far at 635RW we are safe.

[lock]

How do you know which red/white wire to use? Im guessing the one that is a heavier gauge than the other ones.