Supercharger on 300 6 misfiring at top end.

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djfalcon10
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Supercharger on 300 6 misfiring at top end.

Post #1 by djfalcon10 » Sun Jul 30, 2017 5:37 pm

I have a paxton supercharger on my 300. I have ngk plugs. Gapped at.30. I took it out and got on it. Soon as it get above 4000 rpm. Its starts poping. Now i have notice on my fuel pressure it set at 6 psi. When i floor it it went down to 4 psi. My friend tells me i need a boost regulater. And that i am leaning out the motor. So please help so i can get it to run great. Thanks

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MechRick
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Joined: Wed Jan 04, 2012 7:43 pm
Location: Las Vegas, NV

Re: Supercharger on 300 6 misfiring at top end.

Post #2 by MechRick » Sun Jul 30, 2017 7:44 pm

Draw through or blow through?
1994 F150, 4.9L/ZF 5 speed, C-Vic police driveshaft
EFI head w/mild port work, 3 angle valve job
1996 long block, stock pistons, ARP rod bolts
Stock cam installed straight up (aluminum cam gear)
Hedman header, full mandrel bent duals, crossover, super turbos
viewtopic.php?f=2&t=73244
Bronco II with a 2.3L swap viewtopic.php?f=13&t=72863

djfalcon10
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Posts: 118
Joined: Mon Jul 18, 2011 12:02 am

Re: Supercharger on 300 6 misfiring at top end.

Post #3 by djfalcon10 » Sun Jul 30, 2017 11:07 pm

Blow thur

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MechRick
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Joined: Wed Jan 04, 2012 7:43 pm
Location: Las Vegas, NV

Re: Supercharger on 300 6 misfiring at top end.

Post #4 by MechRick » Mon Jul 31, 2017 12:37 am

You need to boost reference the fuel pump.
The one blow thru I built I drilled and tapped the diaphragm reference hole in the mechanical fuel pump and ran a manifold vacuum line to that.
If you use an electric you will need a fuel pressure regulator with a vacuum/pressure port.
Whatever boost you are running needs to be added to the base fuel pressure. For instance, at 6 psi, +base of 6 psi gives you 12 psi while under boost. It has to be this way or the boost pressure shuts off the fuel flow to the carb.
1994 F150, 4.9L/ZF 5 speed, C-Vic police driveshaft
EFI head w/mild port work, 3 angle valve job
1996 long block, stock pistons, ARP rod bolts
Stock cam installed straight up (aluminum cam gear)
Hedman header, full mandrel bent duals, crossover, super turbos
viewtopic.php?f=2&t=73244
Bronco II with a 2.3L swap viewtopic.php?f=13&t=72863

djfalcon10
Registered User
Posts: 118
Joined: Mon Jul 18, 2011 12:02 am

Re: Supercharger on 300 6 misfiring at top end.

Post #5 by djfalcon10 » Mon Jul 31, 2017 7:36 am

Thanks for your help. I am running a electric fuel pump. So i will get the one with the vacuum port.

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