we are trying to figure out how to get more speed out of the 38ZR, we looked at whipples but have heard some bad stories about tuning and drive problems. i figured you guy's would be the best place to start..
i was talking to a guy locally that said we can have the ecu's tuned and pick up some HP and MPH is this true? is there a "chip" kit that is worth the time and money to bother with?

I think that Whipple does an ECU re-program that is supposed to be worth about 40+ hp.

Chris

How much MPH are you looking for ?

5. blowers aren't out of the question i just don't want to have to buy drives and blowers, plus i don't want the tuning issues that i keep hearing about

I believe you will need to run 91 octane with the upgrade. Something to consider. Keep us posted if you go this route. I may be interested in doing the same to my 525.

Yup,
You do have to then run 91 octane with the re-program.
Depending on the hull efficiency, it should give you 2-4 mph.

Chris

If blowers are set up right and tuned properly when installed they will run as trouble free as anything else . It just takes time to set them up and time = money . Good luck

Thats the truth !

I think you guys may be stretching the hopeful gain you would see on a Mercury racing HP525 EFI engine with a reprogram alone. Plus 40 HP won't happen and even plus 20HP would be a stretch!
Trust me when I say Mercury Racing has been tuning these engines for optimum performance on their dynos and at Lake X and in all the racing series for several years and this engine will make about 540-550HP at the crank max no matter how much you try and tweak the program. If you can take any EFI computer controlled marine engine and gain 20-40HP more, the engine's ECM was improperly tuned to begin with!
The HP525 EFI Mercury Racing engine is NOT improperly tuned !
You would be better off to spend your time and money on prop, drive and bottom fine tuning and leave the ECM alone. If you are ready to go thru the engine and lets say add a little compression or a few cubes, then that's a different situation and 40-100HP gains can be had on this engine quite easily but also more expensively.
I know we would all like to see big HP gains for small dollars, but its generally not ever going to happen!
If it does, PINCH YOURSELF! You're probably dreaming and you need to wake up now!

Best Regards,
Ray @ Raylar

I have a mercury 600 sci that whipple reprogrammed and I have to say that it was a great move. I don't have dyno results but I am absolutely certain that the hp gain is more than 40 hp. Torque has been greatly increased. Motor is much more responsive. Top speed so far 91 mph with two guys 1/2 tank of fuel, ideal conditions. Prior to this upgrade the boat would run 86 mph under the same or very similar conditions. I would have to strongly disagree that Mercury has programmed this engine for maximum performance. Maybe this is true for the 525 but not for the 600 sci. After the reprogram this feels like a different beast. All speeds are accurate gps speeds.