Too much fuel on idle with Whipple supercharger system

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07-04-2025 | 01:15 PM

#11

Mankka

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Of course.
I have installed Whipple supercharger kit for 350 MAG and 350 black scorpion. I purchased kit direct from Whipple. I also installed oil cooler. 350 Magnum MPI 05-08 (ECM 555) SC KitFinish: Black
SCP: 4.0"

350/377 Oil Cooler kit (2" x 16" oil cooler, 2" clamps, 8AN

Recalibrate ECM/PCM555 for Whipple SC kit

I contacted Whipple for trouble shooting. Their latest email for me was to ”Try decreasing the fuel pressure a few lbs”.

I tested MSD ignition this week. Engine did idle better with it but idle was wavy and alarm system was constantly peeping. Now back on Mercruiser original ignition system.

07-04-2025 | 03:40 PM

#12

Mankka

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Quote:

Originally Posted by F-2 Speedy

How about you back up and tell us all the components you have installed, we dont even know the model blower

I ordered supercharger system straight from Whipple.

350 Magnum MPI 05-08 (ECM 555) SC Kit
Finish: Black
SCP: 4.0"

350/377 Oil Cooler kit (2" x 16" oil cooler, 2" clamps, 8AN fittings/hose, inverted flare fittings)

ECM/PCM555 for Whipple SC kit

I contacted Whipple for trouble shooting and their latest email was that ”Try decreasing the fuel pressure a few lbs”.

Last edited by Mankka; 07-04-2025 at 03:44 PM.

07-04-2025 | 03:59 PM

#13

F-2 Speedy

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From: Midwest & T-Rock

this one ? is it designed to work with your factory fuel ( cool fuel ) system

https://whipplesuperchargers.com/i-2...-scorpion.html

07-04-2025 | 04:06 PM

#14

Mankka

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Quote:

Originally Posted by F-2 Speedy

this one ? is it designed to work with your factory fuel ( cool fuel ) system

Yes, that it is. And yes it is designed to work with factory fuel system.

07-04-2025 | 04:23 PM

#15

F-2 Speedy

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From: Midwest & T-Rock

Is there an external regulator off the back side of the fuel rail ? I cant open the instructions......fuel pressure gauge reading.............since its a new kit Id contact whipple monday.Ive only done BBC installs

07-04-2025 | 04:30 PM

#16

Mankka

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I think that there is only one fuel pressure regulator close to the alternator where is fuel pump and fuel filter.

Fuel pressure is 41 PSI on idle with vacuum and with out wacuum 43 PSI. I did send email to Whipple. Have to wait for their reply.

07-04-2025 | 04:56 PM

#17

F-2 Speedy

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From: Midwest & T-Rock

So do you have a scanner or software to talk to the PCM ? are you sure the distributor and timing is set correctly

07-05-2025 | 01:46 AM

#18

Markus

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From: Gothenburg, Sweden

Quote:

Originally Posted by F-2 Speedy

So do you have a scanner or software to talk to the PCM ? are you sure the distributor and timing is set correctly

Definitely check timing.

07-09-2025 | 08:27 AM

#19

Mankka

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Thank you for you all that have comment to this topic.

Yesterday we unplugged 3 of 6 Whipple fuel injectors. We did idle engine with 3 injectors and the idling was really nice. Engine also did respond throttle nice from idle to about 2000 rpm.

After that we plugged all 6 injectors back to use and again engine idle very very rich and rough