Merc 496HO Motorola PCM555 ECM
#1
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Joined: Jun 2021
Posts: 3,459
Likes: 2,089
From: SW Ohio
Guys,
I have a Motorola PCM555 ECU, in perfect working condition, flashed with Whipple’s stage 2 tune with ProCharger note on the Whipple request ticket. $1000, plus the ride.
I also have the cam ready to ship for anyone looking to upgrade their MAG to HO. $300 plus the ride.
I also have the complete, unaltered harness. $500, plus the ride.
I can get pics on request.
Thanks. Brad.
I have a Motorola PCM555 ECU, in perfect working condition, flashed with Whipple’s stage 2 tune with ProCharger note on the Whipple request ticket. $1000, plus the ride.
I also have the cam ready to ship for anyone looking to upgrade their MAG to HO. $300 plus the ride.
I also have the complete, unaltered harness. $500, plus the ride.
I can get pics on request.
Thanks. Brad.
#3
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Joined: Jan 2005
Posts: 4,817
Likes: 373
From: IL
The whipple Pro charger calibration is the ECM issue, who ever buys it will have to spend another $700 to recalibrate it to a Mag Ho,
In the past , anytime I had a left over used HO cam , I got $125-$150 for them,
have a brand new 496 block the I kept for a spare and about a year ago I I decided to sell it and post it for $1500 and I still have it, which is probably a good thing , rather have the block just in case lol
In the past , anytime I had a left over used HO cam , I got $125-$150 for them,
have a brand new 496 block the I kept for a spare and about a year ago I I decided to sell it and post it for $1500 and I still have it, which is probably a good thing , rather have the block just in case lol
Last edited by boatnt; 01-20-2026 at 02:08 PM.
#4
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Joined: Jun 2021
Posts: 3,459
Likes: 2,089
From: SW Ohio
The whipple Pro charger calibration is the ECM issue, who ever buys it will have to spend another $700 to recalibrate it to a Mag Ho,
In the past , anytime I had a left over used HO cam , I got $125-$150 for them,
have a brand new 496 block the I kept for a spare and about a year ago I I decided to sell it and post it for $1500 and I still have it, which is probably a good thing , rather have the block just in case lol
In the past , anytime I had a left over used HO cam , I got $125-$150 for them,
have a brand new 496 block the I kept for a spare and about a year ago I I decided to sell it and post it for $1500 and I still have it, which is probably a good thing , rather have the block just in case lol
I was of the impression that Merc did the reflash for minimal cost. No?
Noted on the cam.
FTR, I was presented with the opportunity to buy a complete engine, plus some metal in the oil, for $450. I spoke with my builder about buying it and rebuilding it with forged internals to flip it. He was all for it, but we never moved on it. I don’t even know it they guy has sold it or not.
Thanks. Brad.
#5
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Joined: Jan 2005
Posts: 4,817
Likes: 373
From: IL
BoatNT,
I was of the impression that Merc did the reflash for minimal cost. No?
Noted on the cam.
FTR, I was presented with the opportunity to buy a complete engine, plus some metal in the oil, for $450. I spoke with my builder about buying it and rebuilding it with forged internals to flip it. He was all for it, but we never moved on it. I don’t even know it they guy has sold it or not.
Thanks. Brad.
I was of the impression that Merc did the reflash for minimal cost. No?
Noted on the cam.
FTR, I was presented with the opportunity to buy a complete engine, plus some metal in the oil, for $450. I spoke with my builder about buying it and rebuilding it with forged internals to flip it. He was all for it, but we never moved on it. I don’t even know it they guy has sold it or not.
Thanks. Brad.
as for the engines, yes you can buy a used worn out long block for less but by the time you pay the machine shop to bring it back to specs you will be upside down and you still have a old worked over engine , that’s why I thought somebody that knew the value of a brand new engine would’ve picked this up a long time ago, but I still have it and it’s probably best I keep it anyways, you never know.
#6
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Joined: Jun 2021
Posts: 3,459
Likes: 2,089
From: SW Ohio
Mercury will not program a used ECM, there’s only two places that I know of, Whipple and Mark boos at precision Marine ,last one I had calibrated was a year ago and it was $700
as for the engines, yes you can buy a used worn out long block for less but by the time you pay the machine shop to bring it back to specs you will be upside down and you still have a old worked over engine , that’s why I thought somebody that knew the value of a brand new engine would’ve picked this up a long time ago, but I still have it and it’s probably best I keep it anyways, you never know.
as for the engines, yes you can buy a used worn out long block for less but by the time you pay the machine shop to bring it back to specs you will be upside down and you still have a old worked over engine , that’s why I thought somebody that knew the value of a brand new engine would’ve picked this up a long time ago, but I still have it and it’s probably best I keep it anyways, you never know.
Ah. Gotcha. For some reason I thought I’d read someone suggest sending an ECM to Merc for a “back-to-factory” reflash. All good.
I missed the “brand new” about your block.
Thanks. Brad.




