502 MPI upgrade results
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articfriends (09-21-2021)
#13
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how did the motor run this year, going to do the same upgarde to mine. Did you have the ecm tuned on the dyno or did he just sent you a proven tune and you wanted to see what it would pull?? thanks
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Motor runs awesome. Bob gave Mark the info he needed and Mark did the tune through the mail and it was perfect. We run every engine on the dyno.
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Alex, did you run the boat on the water afterwards with a 02 sensor on it and see what the afr's looked like? I dynoed before at Crocketts and fuel numbers looked pretty good then as installed in the boat there were rich/lean spots that I cleaned up by re-tuning on the water. I have never ran Marks tunes in antything BUT have talked to him in detail on the phone and I do know on his proven/dynoed tunes he loads them on the dyno at every possible throttle setting and load when dynoing so very little on water tuning is needed or even at all. I have enjoyed learning how to get a close to perfect tune in the boat, its a little harder to do when I am running boost though as its hard to make wfo passes and safely tune it without chancing breaking something or crashing unless conditions are perfect, Smitty
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I just got this off the dyno a couple days ago and think this is a great little package for the 502. The cam is from Bob Madara, the tune is from Mark Boos. Stock 502mpi with the intake dividers cut down and a bit of porting, stainless marine exhaust, run on the dyno with all accessories, wet exhaust through GGB mufflers. It idles at 600rpm and the tune was perfect. You could bump the rev limiter up and make a bit more. It made 508hp just before it hit the limiter at 5350rpm. Thanks again to Bob and Mark!
#18