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Old 04-13-2010, 02:22 PM
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If your running twin merc 454 mag MPI's with a little ECU work and different exhaust and breathers. Should we use a booster if all we can get is 89 or 91 at the dock..
Stock comrpression.. Or are we good at 89-91... Does the lead cause any issue with the fuel injection?
Would like these motors to last me awhile...
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Old 04-13-2010, 04:45 PM
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Originally Posted by silent lucidity View Post
If your running twin merc 454 mag MPI's with a little ECU work and different exhaust and breathers. Should we use a booster if all we can get is 89 or 91 at the dock..
Stock comrpression.. Or are we good at 89-91... Does the lead cause any issue with the fuel injection?
Would like these motors to last me awhile...
if its stock compression ratio then you can run essentially anything you want. but thats assumming that your " little ecu" work didn't push the ignition map straight into detonation all the time ...
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Old 04-13-2010, 11:44 PM
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You should be perfectly fine with 89 octane. I have CMI's on my 502 mpi's and run 87 octane. No ecm work though.
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Old 04-14-2010, 09:31 AM
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Default little ECM work

Originally Posted by Griff View Post
You should be perfectly fine with 89 octane. I have CMI's on my 502 mpi's and run 87 octane. No ecm work though.
Tyler Crocket did some ECM work based on me adding the EMI off shore exhaust and vortech breathers.
he said they added a little more fuel and remapped the timing curve I think and bumped my rev limiter 250 rpms since I was hitting it,
All this talk now I hope I'm ok... sure don't wax these motors they only have 200hrs...
My wife always says " when can you just leave "chit" alone...
DANG she may be right.
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