I'm curious. If you didn't dyno the engine, how do you truly know you're making 500HP? How many hours on this engine and what RPM does it turn?? Have you had any issues with it?

Don't take it the wrong way, because I am not trying to "knock" your build in any way. I too am a very budget minded boater. Theres a few things in your build I personally wouldn't use in a bbc marine Hi performance engine. This is just my opinion so take it with a grain of salt.

I would not use 199.99 dollar Chinese retrofit ebay roller lifters. When and if a roller breaks, it gets ugly fast.

130psi on the seat is a little light imo for a bbc hyd roller that might turn some rpm. I know nothing about the howards valvesprings you have, other than in the howards catalog they are listed under flat tappet springs.


With the piston/head/stroke combo you're running you have to be somewhere around 10:1, possibly more if the block and heads been cut. Too much for a iron headed marine engine imo. Not sure I personally would call a 10:1 iron headed marine engine "sane" or "conservative" . But if it works for you, that's good.

For years I've been talking to pro marine engine builders, picking their brains, reading their posts, taking their advice. One area that is always stressed, is valvetrain. You do not want to cut any corners here. Quality valves, endurance springs properly set up for the application (pressures), quality lifters, pushrods, rockers, etc.

Am I saying the OP needs cnc heads, carilllo rods and billet cranks, absolutely not. But I couldn't sleep well at night knowing I recommended ebay lifters, soft valve springs, and a high compression setup. I look at it this way. Gas is 4.00 a gallon. If you save 1000 dollars on a engine build by going with lesser quality parts, in my boat that's a tank of fuel. Single engine boat maybe 2-3 tank fulls. I'd prefer to take a couple weekends off of boating and use the good stuff. Then it will last many tank fulls of gas.

If you have a few hundred hours of turn key operation on your build, feel free to tell me to stick my thoughts up my @$$. Because you would be the one with more cash in your pocket! I do a little different kind of boating. I have a big old heavy boat that gets held on the pin for long stretches on lake Michigan. I need to stay far away from detonation and need a valvetrain that wont let me down.

You definitely don't want to run the cam they used.

Even being conservative with cam and compression, 1hp per cubic inch is realistic. It just takes the right combination of parts.

I'd get fired for sure. I cant see why everyone wouldn't run a supercharger :lolhit:

Hey thunder thanks again and I would trust ur word over most so far u have been on top of everything so far.

I'm curious. If you didn't dyno the engine, how do you truly know you're making 500HP?
Not my first marry go round. I've had dynoed motors before and I'm being conservative with this one. Also its pretty much a copy of a motor that dynoed at 575hp.
How many hours on this engine and what RPM does it turn??
Built it in the winter/spring of 2011. Don't have an hour meter but there is a reason my house is 400 feet from the water. 5200@WOT. I could zing it up more with a smaller prop but I'm not into beating the crap out of motors anymore and tend to take longer "rides". Cruse at 3400 rpm's.
Have you had any issues with it?
Nope except gas money. lol

Don't take it the wrong way, because I am not trying to "knock" your build in any way. I too am a very budget minded boater. Theres a few things in your build I personally wouldn't use in a bbc marine Hi performance engine. This is just my opinion so take it with a grain of salt.


No issues. I'll tell you first hand that I'm not building the most expensive I can and to be honest I'll also tell ya that if you are dumping 10 or 12 grand into a motor to get 500 solid HP you are crazy unless you have a boat to match. I see all the time, boat for sale, $16,000, $7,000 without motor. The way I look at it is there are certin levels of motor building and sadly the improvements are less and less as you go and are more and more expensive for smaller and smaller gains. Unless you plan on doing everything to match an expensive set of heads will get you about nothing. As an example most people who are rebuilding a 330/454 the first thing they will do is dump the peanut port heads. But any honest builder will tell you that for the rpm ban that boats run at those heads are fine and better in most cases up to 450hp then a "better set" and a lot of times they will either be a waste of money and/or even hurt your performance but everyone still wants new heads.
I would not use 199.99 dollar Chinese retrofit ebay roller lifters. When and if a roller breaks, it gets ugly fast.
Been using the Max roller lifters for about 4 years now in a couple/three motors. Never a failure. Had the top end in one motor not oil properly for other reasons and ran it like I stole it for over an hour and still didn't have a failure. They have my business. Also been told by a couple sources that Crain and others just relabel the same companies lifters (different looking ones) with their name. Its their in house brand.

130psi on the seat is a little light imo for a bbc hyd roller that might turn some rpm. I know nothing about the howards valve springs you have, other than in the howards catalog they are listed under flat tappet springs.
Recommended spring for the cam but in a single spring and damper so the heads didn't need to be cut for a double spring. It was a short cut but after talking to Bob lets just say I did it with out loosing a second of sleep over it.


With the piston/head/stroke combo you're running you have to be somewhere around 10:1, possibly more if the block and heads been cut. Too much for a iron headed marine engine imo. Not sure I personally would call a 10:1 iron headed marine engine "sane" or "conservative" . But if it works for you, that's good.
Should be from 9.75 to 10 to 1. Runs on mix of 89 and 92 oct. Depends on how much money I have in my pocket. Used a decent head gasket, good pistons, rods and such. I have to disagree. We built plenty of motors when we were kids and the formula was always a certain Crain cam, Edelbrock intake and carb and .210 dome pistons (9.75 to 1) in every BB we did. Never had a failure due to the compression.

For years I've been talking to pro marine engine builders, picking their brains, reading their posts, taking their advice. One area that is always stressed, is valve train. You do not want to cut any corners here. Quality valves, endurance springs properly set up for the application (pressures), quality lifters, push rods, rockers, etc.

Ya but how much do you want to spend on it all?? The sky is the limit. And really what is the difference in a $120 set of Comp push rods compared to $320 push rods? Just maybe if you are doing the Bahama 500 and doing 6000 rpms for 250 miles you may want to use the $320 ones but in most cases boaters will run at wot for 45 second to a minute before pulling back. IMHO way over kill.
Take a 330 hp mercruiser apart and see the thinnest, thinest things they could use but yet 330hp all day long for years on end with people beating the piss out of them. So you know in a way they were over build so they would last longer then their warranty. Just upgrading to the next level on any part of the valve train is more then most builds will ever need.

Am I saying the OP needs cnc heads, carilllo rods and billet cranks, absolutely not. But I couldn't sleep well at night knowing I recommended ebay lifters, soft valve springs, and a high compression setup. I look at it this way. Gas is 4.00 a gallon. If you save 1000 dollars on a engine build by going with lesser quality parts, in my boat that's a tank of fuel. Single engine boat maybe 2-3 tank fulls. I'd prefer to take a couple weekends off of boating and use the good stuff. Then it will last many tank fulls of gas.

If you have a few hundred hours of turn key operation on your build, feel free to tell me to stick my thoughts up my @$$. Because you would be the one with more cash in your pocket! I do a little different kind of boating. I have a big old heavy boat that gets held on the pin for long stretches on lake Michigan. I need to stay far away from detonation and need a valve train that wont let me down.

Again, I'm not a master motor builder but I am a master web searcher. You can find any motor built and even custom built motors by some of the best in the business on-line and even though they wont list whats in it someone who works there or bought one will and every single part down to the bearings. Its almost to easy and your head will spin on how much is out there. You didn't hear it from me but 4X4 racers love to share secrets. I find a motor for the wot and cruise numbers I'm looking for. Research all the parts and search the web. I find something to good to be true and research it to prove it one way or another. Like Howards cams. Usually 1/2 price of other cams. Why? After trying to have Bob custom grind me a RR flat tappet cam and not being able to find a Billet to make it out of Bob told me that there is only 2 cam billet makers (they were on strike) but they are both as good as the other. So that would mean there was no issue with the billets them selves for the price difference. It must be grinds but yet you can find any numbers you want and Crain ended up being the company with the screwed up grinds but they still went for twice the money. Then there is Scat. My first dealing with them was like a decade ago. Installed their roller rockers on a 360 Chrysler and the first rotation half the poly-locks popped off like popcorn. They replace it with a new set and the rockers seize on the bars 10 minutes from the dock. Today, especially when it comes to cranks Scatt is considered one of the better makers. Folks don't like something they will tell you and as I'm sure you know there is a forum for everything.
Last, this is the 6th or 7th version of this very motor. The version I have now is going on its 3rd year and is the best one so far so much so that I'm not taking it any further. Solid Hp on a budget.

hey bossbultsma i have a bunch of performance parts you may be interested in carbs,intakes,cams,lifters,heads,roller rockers let me know if interested.

keep it goin...

Talking about the fight or the build.

No fight. Just different people do things different ways. Some of us have unlimited budgets. Others have broken their budgets long ago. I personally like to pass on anything that's worked for me just in case it may work for someone else. No reason for anybody to go down the same roads I've been on it unless they lead somewhere.

I can promise you those lifters you are talking about are not the same ones coming from Crane Cams. Chase knight would flip over backwards if he herd some one say that they were the same as the cheap 199.00 EBay lifters.

Irwin,
I'm starting to take offence here.
Crain has been junk for years. There I said it. I try not to cut on other manufacturers products but the facts are the facts. I know when they were taken over recently every cam that they already cut had to go in the trash for being way out of spec. How many of those cams do you you think made it out on the market before they closed? So every manufacturer has their issues. Scat used to be junk. Now they are considered a premier crank maker. Don't believe me talk to a machinist who does cranks. So to each his own.
Before I use anything I always do a ton of research online, phone calls to people use them and machinist that see the failures. No one I talked to said the lifters were bad so I gave them a try. Beat the piss out of them in the first motor I used them in and since have used them in a couple other motors. All is good. So I will stick with my "cheap eBay lifters" until something changes.
Also remember I understand that some of you are building hundred thousand dollars boats and you want the best of the best. I probably would too. I mean when you spend six or seven thousand on a set of exhaust what is a couple hundred extra dollars on a set of lifters. I use Mercruiser aluminum 496 exhaust. If I was six or $7000 into exhaust it would almost double the cost of the boat. lol. Just not worth it for me. But there is some of us out there that do this whole boating thing on a budget and like I said I just like to pass on what has worked for me because I wish somebody would've for me years ago when the whole goal was to just get on the water. Why do you think you see so many boat sitting around that will never be used? 3 to 5 grand for exhaust, five grand just to build a motor out of what you have. No one is going to dump 10 grand into a boat that's only worth 10 grand if it was perfect.
One of the things that irks me the most is when someone will come on here and say I got a 330 Mercruiser and wants to add power. Same post, over and over. "Dump it and get a 502". Seriously? A couple thousand dollar or less upgrade and the first some want to do is turn it into a $10,000 plus upgrade. Not everyone can afford it. I'm just trying to get it so a few more can.
I did what I did, it worked and here are the results. You can make up your own mind from there.

Think about this. Howards cams are half the price of Crains. Why? Their specs are on. Also the billets come from only two manufactures that according to a well respected cam guy that is recommended all the time on this board says that both manufactures are just as good as the other. I know its hard to believe in this day and age but sometimes more expensive is not always better.

f-insreenname I agree with what you are saying.Not all people have deep pockets like a lot on this site.I come from the old school the poor school.I have had many boats in the last 50 years and some that ran the best were from used parts I picked up at swap meats and from guys who didn't need them.Horse power has a lot to do with money invested but I think much more to do with knowledge and determination.As for Howard stuff it works!!! they been in the business longer than most guys have been boating and still doing fine.Everyone has a opinion and not all big buck engines run My 2cents JOHN SR

Yea some people on this website really need to understand that not everyone is loaded especially when they are giving advise, ive been steered wrong a few times because of it myself. Theres the best way of doing things and the way that works good enough, i try to find somewhere in between

Please do not be offended. Im just stating that the lifters that you chose to run are not the same as crane cams that's all. They may work perfectly fine for what your doing. Im sorry to offend you I never meant for you to be offended. Im personal friends with chase knight from crane and i asked him one time if his lifters were made by morel because they look very similar and his head about spun around.....lol. All that matters is that your way of doing things is working. So keep doing it and having fun.

I love all the advice u can get on this site some guys are great at giving it. But there are some that do expect everyone to have money. I come from have a family to provide for and I work in the construction bussiuness so I don't make much money compared to others. I boat because I live this sport and its super fun. Granted it so dang exspensive to have a power boat, but I don't try to be cheap I just do the best I can with what I have. Also any motor builder out there know that the quality of the parts and the time u out into the motor is what make a great motor. It's not about who can stick the most money in there motor and have the fastest boat it's about who's not broke down in the water. Cuz last season I was broke down ever other weekend. So this year I'm hopeing not to breack down at all that why I ask so many questions. I want to learn as much as I can, so I can build a reliable boat and have a few hp's behind it to.

So thank u to all u boaters out there that give advice and are proud of what they do in this sport.

Well just ordered my crank and pistons I know it's a little late. But my interior bill was a lot more than I wanted it to be and could afford. So the motor will go to the machine shop as soon as they get in so hopefully I can have her running by the end of the month.