User Tag List
Thanks: 0
Results 1 to 7 of 7
Thread: 300xs mad efi mid power loss
-
01-23-2022, 12:30 AM #1New Member
- Join Date
- Jul 2020
- Location
- Australia
- Posts
- 2
- Thanks (Given)
- 0
- Thanks (Received)
- 0
- Likes (Given)
- 0
- Likes (Received)
- 0
- Mentioned
- 0 Post(s)
- Tagged
- 0 Thread(s)
300xs mad efi mid power loss
Hi all, please feel free too weigh in.
Just changed over to a Mad EFI 15 mid on my 300xs
Issue I have run into is that I have lost bottom end and top end power. The very same prop that would pull a single skier at 90-91mph and 2 skiers 84.4mph now struggles to pull 1 skier out without a massive whip and only getting 83mph.
I have changed the jacking plate so the offset to the transom is same as when the 20" mid was fitted.
Has anyone had similar issues?.
Is there something else that needs to be done to exhaust?.
Does anyone do ecu reflash to accommodate mid section disruption to factory power curves.
-
01-23-2022, 05:46 AM #26000 RPM
- Join Date
- Nov 2006
- Posts
- 1,495
- Thanks (Given)
- 13
- Thanks (Received)
- 129
- Likes (Given)
- 70
- Likes (Received)
- 626
- Mentioned
- 35 Post(s)
- Tagged
- 0 Thread(s)
Mad EFI Mid
The exhaust breathing on a MAD EFI mid is completely different than a stock mid. I would guess that there is no exhaust back pressure pulses going on with the MAD EFI mid and it's affected top and bottom end performance. Not sure that ecu reflash would help? What exhaust tuner are you using? OEM?
-
01-23-2022, 06:16 AM #3New Member
- Join Date
- Jul 2020
- Location
- Australia
- Posts
- 2
- Thanks (Given)
- 0
- Thanks (Received)
- 0
- Likes (Given)
- 0
- Likes (Received)
- 0
- Mentioned
- 0 Post(s)
- Tagged
- 0 Thread(s)
-
01-23-2022, 09:33 AM #4
The mid change shouldn't have slowed the boat down. There is either a setup issue or assembly issue. Since we took 5 inches off and the jackplate was changed was it lowered so the geaecase can run in the same prop to pad height? Are your rpms the same as before when running wide open? Feel free to call me (239)293-4731 or email info@madefi.com
-
NAVISPEED1, tom kennedy liked this post
-
01-25-2022, 08:51 AM #5Screaming And Flying!
- Join Date
- Jun 2007
- Location
- Singapore/Melbourne/Italy
- Posts
- 9,109
- Thanks (Given)
- 1010
- Thanks (Received)
- 356
- Likes (Given)
- 4327
- Likes (Received)
- 1976
- Mentioned
- 8 Post(s)
- Tagged
- 0 Thread(s)
My guess is if the exhaust flows with less restriction it has made it lean?
-
01-25-2022, 01:38 PM #66000 RPM
- Join Date
- Nov 2006
- Posts
- 1,495
- Thanks (Given)
- 13
- Thanks (Received)
- 129
- Likes (Given)
- 70
- Likes (Received)
- 626
- Mentioned
- 35 Post(s)
- Tagged
- 0 Thread(s)
-
01-25-2022, 02:41 PM #7
Call Todd you have missed something I have done several and never saw a power or speed drop. Every Super Stock boat is running the 15 inch can and Mercury hands them stock sealed ECU just before the race , none of the racers would run something that hurt speed or power.
24 Twister
-
tom kennedy liked this post
Similar Threads
-
300XS Soft Primer Bulb / Power Loss After High RPM Runs????
By wasvette in forum Technical DiscussionReplies: 19Last Post: 06-27-2021, 07:35 PM -
Problem with 2017 300xs .. loss of 1000rpm
By Pachanga_rick in forum Technical DiscussionReplies: 32Last Post: 07-25-2018, 04:32 PM -
2.5 EFI power loss
By Propman in forum Technical DiscussionReplies: 2Last Post: 05-13-2002, 06:14 PM -
How Much Power Loss
By Craig Knight in forum Technical DiscussionReplies: 2Last Post: 08-17-2001, 06:08 PM