Young Performance

Actually, yours was a little different than the others. It was a tad smaller than Keegan's cam, but you had a smaller pulley on the sc and he had a little more compression. I really liked your setup and I have a great tune for it now. That is the one that I would duplicate on future 575's.

Thanks everyone for the recommendations.
Eddie

1 MAIDEN AMERICA

I'll have to guess on springs but I imagine he went with Crane's recommendation on the cam card.
Springs-Crane 99896. 150# and 460# open
Stock rockers and studs

iliveonanisland

I always run ARP rocker studs . Cheap.insurance you won't blow a day of boating and idle home for.hours on one engine...

Rookie

iTrader: (4)

As others have said Eddie could probable do the cam and tune your ECM.

mcprodesign

you went with aluminum heads and chit . He redid the whole top end . There is no roller replacement for some stupid reason

mcprodesign

you always have good info. But stock computer ? You must have remapped or retuned on the dyno though , right?

JRider

iTrader: (1)

The stock 575 tune is very rich and he can most likely get away with it. Another possibility is changing the regulator to up the fuel pressure. I copied someone elses setup and used the map they had on mine. I can tell you that the stock map on the 575 can wash down your cylinders, not good. There is no way in hell I would run a stock map after somebody elses tune, no annoying high idle is one reason, another is no soot on my transom.

1 MAIDEN AMERICA

Stock computer. Stock fuel system.
When I start the engines they idle fast but drop down quicker than I typed this sentence(hunt and peck)
I idle through the cut for an hour and no stumbles.
There is a rich spot at about 2000RPM after idling for a while. I only experience it getting back on plane but it's short lived because I have to rev it to 4000RPM to get it up.
If I go to the mountains it's worse but doable and I'll have a little bit of soot.
Most of my boating is at sea level and soot isn't a problem.
BTW just changed spark plug wires. 400+ hours. Nothing changed. When I do plugs at 100 hours or so, they're decent looking, it does sound a bit more crisp afterwards.
The extra fuel washing down the cylinders is great for washing the water from reversion out! Seriously though, it's not an issue on my engines for whatever reason. I do have dual IAC's where I've heard some only have one so maybe that's something to do with it.

1 MAIDEN AMERICA

Not to say that wouldn't like to try a custom tune but no way would I do it off a dyno so for now, it is what it is.
BSFC numbers were .6@2300 rising to .67@3000 dropping to .5@3300 dropping to .46@3500-4500 rising to.51@4900-5200 dropping to .43@5450. HP was still climbing when it hit the limiter but get rid of the limiter and I'll need to change the fuel system. I've heard all I need to do is change to a 525 pump but I'm sure that would change my interim numbers too and then more tuning.

MILD THUNDER

iTrader: (3)

Did your dyno have o2 sensors ?