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.

5 MPH would equal over 100HP gain. No way a fuel or spark curve can give that increase has Raylar said above. I'm sot sure of how the 600 controls boost, but if its in the program, only boost could give you that much gain. Glad it worked for you.

we talked to a guy @ mercury and he told us the same thing you just said Ray, in the end he said whipples or leave it alone, he said there isn't a tune anywhere that will better the 525, he also said that the 525 will respond and handle the boost with ease. after doing more research it looks like as long as i don't cowboy the sticks the drives should be fine for a while. we are looking to find someone to install and dyno tune for us....
so a new question for you guy's???? we live in cincinnati, our boat is at Lake Cumberland within a reasonable distance who would you recomend i trust to intsall whipples? i don't want to be posting whore stories about being screwed so i'd rather pay a little more and get it done at a reputable shop

Relaxalot:
Glad to hear a reprogram on your (supercharged) 600 Merc SCI added power and performance. Dustin at Whipple is an expert on supercharging and reprogramming and if anybody can extract more power from a supercharged motor it will be someone like Dustin who specializes in blower motors. I also suspect that knowing the Merc 600SCI was a very conservative offering ie the 700 SCI that replaced it . I suspect that the reprogram kicked the boost bypass level down a few notches and is increasing boost pressures up a bit to allow the added horspower along with a few neccessary fuel and spark curve changes this would neccessitate.
This however is not the case with the normally aspirated HP525 EFI engine and I am glad to hear that Mercury concurs since they know better than anyone here!

Show-en-go-h20: Whipple makes some of the best supercharger upgrade systems and products in the world and I am sure with the right investment Dustin at Whipple can hook you up with a good system for your HP525's based on your actual needs.
Just remember that as complexity increases and boost goes on an UP that the cost of ownership, maintenance, fuel cost and overhaul periods and costs also go up. do not expect your supercharged HP525's to be as reliable, long lived or reasonable to operate to STAY THE SAME!
Prepare your self for the changes and if they fit in your picture and budget - GO FOR IT!! and have fun going faster with WHIPPLE!

BestRegards,
Ray @ Raylar

The results that I have are very real. I did not mention that another change I made to the motor was to add a separate pickup on the bottom of the hull to supply the intercooler only. The intercooler dump is now dumping overboard instead of into the exhaust. The reprogram on the 600 has been great. The 525 is a different animal. I am not an engine expert. All I was saying that what Whipple promised was delivered in my case. I think that the 600 must have been detuned to go easier on the XR drive. It is true that I have spent some money and time on this but I am happy with the results. As for the Raylar upgrades, I know several people that have done them and they are happy also with the results. I would consider both choices a possibility and make the decision depending upon other peoples experiences with them and your own unique boating situations. I don't think either choice would be a mistake if you feel the need for speed. Thank you Mr. Raylar and Mr. Whipple for all you have done to improve the boating experience for all of us!

Young Performance Marine. He has done all of our whipple work and does a great job.

I can tell you, almost all OEM engines, auto and marine have something left in them. Not all, but most. The typical reason is the octane levels and the safety margin so they don't really leave something on the table, but its what they deem safe at a certain level. 525HP EFI's don't have knock systems, some have sensors, but nothing is being done with them. Later motors don't have them installed. They are so safe that you can run them on less than 87 octane and thats one of the reasons it's such a great motor. You can just abuse them and abuse them and they just keep going.

But with a 598/610 lift cam, and 230/236 camshaft, the engine does not stop pulling at the 5400rpm limit. Also, 28deg's is not perfect for power on that engine, it's actually a bit conservative. Some go to 34 right at the RPM limit, but not at 5200 and below. Even the 500HP EFI's were programmed similar, 28deg until 5400rpm where the limiter kicked in and timing went to 34. But, all 500's were setup with 10deg base timing, yet the computer was setup for 8, so the motor had 2deg's more then it ever had before. So one can gain 25-40hp, but not necessarily at the identical rpm. Another thing to keep in mind is the variances in calibrations. The motors have been around for quite a few years and I know they've really got them near perfect, but earlier cals were setup a bit more conservative. 32 to 34 deg's is ideal for timing, but it puts you closer to the knock threshold, which is why Mercury didn't set them up that way. Run 91 octane and you increase your knock margin.

No matter what, there still is no comparison to the SC though. Even at low boost, you'll get so much more power that you'll think it's a new boat.

I sent my computers to Whipple to raise the rev limiter. I was not expecting miracles, but mid-range was noticablly better and with the raised rpm's I was able to test different props.
I dont know many pleasure boats with stock 500 efi's running 113 mph.

Hey Show n Go

I just traded a 38ZR w/525's for one w/600's huge difference in speed and acceleration. A lot more fun to drive. What kind of speeds are you getting from the 525's?

Mark

I would also recommend Eddie at Young Performance Marine.