Its really no worse than a 4.5 stroke in a 10.2 deck.

Lots of guys have done it.

Spot on Joe.. I was gonna suggest those as a viable option, with dry tails though

Other then that exhaust posted above what would be some good options? I know I can sell the 496 (Gil) exhaust and risers and it will pay for part of whatever I get. But how would the CMI 525 Headers work compared to EMI Thunders or Lightning Headers???

400.00 for a 4340 forged crank? Just be careful. It's been known many low end cranks advertise 4340 but can be very misleading. I'm not say anything bad about cnc performance at all.... just be careful.

There eagle cranks boxed and everything just clearanceing out some stuff I guess

There's no secret that the majority of high performance boaters are on a budget and currently in, or about to be in over their head. That's fine, wish it wasn't so, but hey this addiction is nuts!

But why do so many egos just not ADMIT to it, accept the fact and boat within their means. No offense to the OP or anyone here, but come on. Especially when there are others willing to help them out! People just don't listen.

The crazy part for me is watching someone think they are building some great engine, and going the extra mile by stroking it to a 540, but skimping on other important parts like exhaust. What a waste of money to only make 500-600HP. Even professional builders are selling their customers on this B.S. but hey that's where they make the profit.

rjewell1988
How long do you actually plan on keeping your boat?
How confident are you that your budget will allow for additional parts like exhaust later? Unexpected things happen, and if your that tight now who knows.
If your father in law knows so much about engines and recommends 540, then why are you asking OSO for help?
PUKE, ugh 540s make me nautious, so lame, so sick of the same ol' builds! Our valvtrain will need freshening multiple times before any part of our shortblocks will prematurely wear. And stop it with the rod angles do some research and calculations before regergitating B.S. continuously repeated by uneducated people.
The entire package is far more important then just cubic inch....Like many have already said.

Mild Thunder Joe has some of the best advice on helping fellow powerboaters achieve their goals on a budget. He has taught us that you have to look at the money spent vs the actual reliability and speed gain. Ask ourselves "is it really worth X,Y,Z to not actually gain much speed?

If your goal is low 70's then really what's the difference between 71.5 and 73? The next milestone is 80 so really no point in wasting money if you're not going to break 80.

OP, I sincerely wish you luck in your build, try to keep an open mind on here and people will be more willing to post advice, if you come on here an expert in bore and stroke, but not in exhaust, the guys with the real knowledge won't waste their time helping you. Plus it makes for great tech discussion, even if sometimes we have to agree to disagree.

This reminds me of a friend of mines experiance. He had a pair of 502's. He was more of a "want reliability" guy, than raw power. He went to an engine builder in Michigan, when it was time to rebuild his 502's, which were healthy, but had some hours on them. He said he would like about 575hp, and RELIABLE.

The engine builder, sold him on converting both 502's, into 540ci, rebuilding the stock GM iron heads. New cams, new lifters, new rockers, converting to carburetor, new intakes, new MSD ignitions, and so on. He spent about 30,000 with this builder. Engines alone, were in the low 20's, and the rest was rigging and what not.

Anyhow, the engines in fact, made right at 575hp. At least thats what the dyno sheets showed. Halfway thru the first summer, one of the engines wouldn't start. Turned out to be an ignition issue, i forget exactly what. Buddy had his marine mechanic friend change the ignition part that was bad(with approval of the engine builder), and next time or two out, the engine melted valves and some chit. Back to the engine builder it went. Engine builder said timing was set incorrectly. Anyhow, engine torn apart, and repaired (at my buddys expense).

Continued to run boat remainder of that season, and some more the next summer if I recall. Then decided to upgrade boats, and sold his. New owner takes delivery, and shortly after, valvetrain comes apart. Broken rocker arms. Tears into the engines, and finds cheap PRW rockers, and some other budget parts. Ends up going thru both engines totally to make them right.

Point of the story, is that my friend, payed a pretty penny, for what he thought, was going to be RELIABLE. He thought he was going to the BEST engine guy around. What he really got, was a boat that really didn't run much faster than it would with a set of Merc HP500's, and the reliability, of a set of merc 900sc's. Bigger cubes aren't always the answer to more power, or more reliability, if the overall package isn't done right.

Stories like this, are why I choose to do my own stuff. I know of several boaters in the area, who have went to this builder, and suffered engine failure after failure, and its always someone elses fault. Either bad gas, someone else screwed with something, act of god, or some crap.

Same builder but I have a different friend just go through similar thing. The builder conned him into turning his hp500s into 540s to make 550ish HP N/A, sold the boat a year later and the new owner dropped a valve. New owner obviously has a new builder, engines are not junk, just cost the original owner WAY more money then needed to not gain much power or reliability.

Another friend has a reliable intercooled blower motor for years, hundreds of hours. I recommended that my friend freshen before it blows. He took my advice just didn't take my advice on who to go to. The same builder talked him into stroking a good running well built 502 to a 540 during freshening, only to go the same speed. Not sure of original power but made 750ish after. Owner only used the boat twice last summer and doesn't have the personality to complain. He does have a big wallet, and also plans to upgrade boats soon so really doesn't matter.

Either way not really the best advice for those two customers, but more profitable for the builder! He's a decent builder not bashing him at all. No one is perfect. Point is not every build is best suited as a 540.

Another great example is Full Force Tim. Bob was his Engine Developer, Not just a parts supplier. We have all agreed already that a 540 was not his best choice, especially reusing his subpar stainless marine gen 1 (not to be mistaken with the better gen 3). Bob doesn't sell exhaust though so why focus on it, especially when most customers have a budget. Tim should have went with a 555,557,565,572,588 and upgraded headers and been alot better off.

Hey did I mention that 540s make me nautious

I appreciate all the input from everyone, and I can promise I am by no means an expert. Right now being a complete newbie in anything to do with V8's and marine performance is try to be a sponge and suck in everything anyone can tell me. After talking with Some of the guys from Molnar in Grand Rapids, Ateco by Chicago, Jim V and numerous others including my father in law I was suggested into building a solid 540 bottom end then upgrade from there. Luckily I have family who knows there way around american motors, which I dont being a european car guy in the past and they are helping build it and with machine work. But most of the people who know motors it seems they dont know marine stuff which Im learning is a totally different animal. Im just glad alot of guys on here and that ive met over the years are a wealth of knowledge. Im really wanting to build a solid 540 which i can add onto over the next few year until I decide to upgrade to something larger boat wise. In all honesty id rather have people suggest me to spend the money, spend it once and not have to do it again which will just cost me more in the long run haha

You'll be fine and respect what your doing. Your wants and needs change quickly in this hobby so chances are you will end up with a different twin app boat al together. Maybe not.... just depends on how much time you have for it and where you plan on running the boat. There's no end to hp and hulls. Next thing you'll be wiping drives out and so on. I think your starting out right and if you listen to Jim he'll lead u in the right direction. Doing a reliable budget build is fine. Also I noticed you must live in or around the GR area. If you need any machine work, balancing etc look up more power racing near Sparta. They dyno also. Good guys. I practically lived there for years.