Need 500 efi Harness - ECU
12-15-2019, 07:58 AM
#1
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Need 500 efi Harness - ECU
Looking for a good 500 efi harness and ECU.
shoot me a PM or email [email protected]
shoot me a PM or email [email protected]
12-15-2019, 08:50 AM
#2
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You can use a mefi 3 MPI harness, you just need to strip the harness of tape and extend a couple wires and reposition the connectors, i didi it on a couple 540's with the 500 EFI intakes
12-15-2019, 09:05 AM
#3
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I understand that I may be able to use the MEFI 1 setups on the 500 EFI and flash. Just don't want to run the the electrical boxes.
12-15-2019, 09:14 AM
#4
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contact Tunnertech Ben on here and see if he has one
12-15-2019, 07:00 PM
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12-15-2019, 08:51 PM
#7
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the hp 500 EFI uses MEFI 3 ecm - a MEFI 1 harness / ecm connectors are different., they wont work. The black production 502 ECM is a different tune than the HP 500 EFI... Performance wise -- the intake and the exhaust and cam basically account for the biggest part of the different tune within the ecms.
The MAX rpms - 502 - MEFI 3 are different between the black side and the blue side as well.
The MAX rpms - 502 - MEFI 3 are different between the black side and the blue side as well.
Last edited by BUP; 12-15-2019 at 08:54 PM.
12-15-2019, 09:12 PM
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for the wire harness themselves - the HP 500 EFI used 2 different harnesses depending on engine serial number per which one is used.
the Mercruiser Black side engines 502 / MEFI 3 harness was different than the HP 500 EFI.
Some of the differences between the harnesses was the location & lengths of the connections for electrical components and the ecm . ----- MEFI 3 - 502 ----- Black engines vs Blue engines.
the Mercruiser Black side engines 502 / MEFI 3 harness was different than the HP 500 EFI.
Some of the differences between the harnesses was the location & lengths of the connections for electrical components and the ecm . ----- MEFI 3 - 502 ----- Black engines vs Blue engines.
Last edited by BUP; 12-15-2019 at 09:16 PM.
12-15-2019, 09:48 PM
#9
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for the wire harness themselves - the HP 500 EFI used 2 different harnesses depending on engine serial number per which one is used.
the Mercruiser Black side engines 502 / MEFI 3 harness was different than the HP 500 EFI.
Some of the differences between the harnesses was the location & lengths of the connections for electrical components and the ecm . ----- MEFI 3 - 502 ----- Black engines vs Blue engines.
the Mercruiser Black side engines 502 / MEFI 3 harness was different than the HP 500 EFI.
Some of the differences between the harnesses was the location & lengths of the connections for electrical components and the ecm . ----- MEFI 3 - 502 ----- Black engines vs Blue engines.
if i used my current ECU’s, would definitely need a new tune. ASM and others can do it - if needed.
Last edited by snowrunner; 12-15-2019 at 09:58 PM.
12-15-2019, 10:54 PM
#10
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Mainly I post what I have experience with and that I personally wrenched on --- Anyways also depending on which serial number run for the HP 500 efi as they used 2 different wiring harness. -- The Cal to change the tune in the ECMs from one engine to another is not that hard if one is set up for it especially when it involves a stock OEM tune. Those are the easiest.
