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-   -   1999 Supercharged 454 problems (https://www.offshoreonly.com/forums/general-q/185287-1999-supercharged-454-problems.html)

lilwigs 05-04-2008 10:28 AM

Well if any of you are curious...I finally figured my issue out this weekend. Thanks for all of your posts, I learned more about this boat and engines than I ever thought I'd need to know. After taking apart my regulator, changing fuel lines, filters, vaccuum lines, fuses, relays etc, I went to my battery switch and discoverd the a ground wire not connected from my main fuel pump. Turns out the factory pump couldn't keep up by itself under boost. What a difference the performance pump makes when its connected. I not get 60lb of pressure at idle and over 70 under 7psi of boost. I might dial that down, but wow what a difference. Over 600rpm higher and 10mph faster. Thanks again, all!

kennyo 05-05-2008 08:35 AM

Now you get to read all about tuning one of these bad boys. Glad you narrowed it down.

DMOORE 05-05-2008 12:36 PM

Good news on getting it running. I would still check on the NGK4, and 5 plugs. They seem really hot for a blower motor.


Darrell.

baronbob 05-05-2008 06:07 PM

Take the boat, as is, to someone who can tune the ecu properly, in the water underway. They may say something about your fuel delivery system, follow their advice, keep the t-stat out until the tune is complete. Going above 3-4 psi you should change out the stock 23# injectors if you have not done so allready.


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