Marine Cam recomendation 489 BBC

[user-30257]

The cam that Chevy puts in the 502 crate engine would probably work pretty well in this type of application. It is fairly small, 210/220 range hyd roller. If it was me I'd keep the cam on the small side in order to enjoy the boat 95% of the time rather than overcam it and enjoy it only 5% of the time.

It's almost 500 inches. A 240@.050 will peak under 6000. If you want peak hp @ idle. Sure put a cam 30 degrees too small in it. As a matter of fact. Might as well put it on a 120 lobe sep, because it's a boat and needs it..

wtf

[user-30257]

If the tune is proper, what ever cam works in the intended usage of stock manifolds ect, the one that makes the most WOT power, will also run the best at part throttle.

The point is ... Power output at any throttle is NOT the main purpose for what this situation requires.

A cam which is around 235 @.050" might make a bit more power at 2,000 RPM wide open throttle than a cam with 220 @.050" but, will NOT have near the same amount of useful properties showing how the engine actually performs while going through a no wake zone or, pulling skiers out of the water or, simply cruising across the lake to a beach, concerned about how much fuel is being used. Power output is only ONE criteria which is to be considered and satisfied.
POWER output is not the "be all, end all" need for most applications yet those unknowing keep going there as if it is.

Yeah, Because an engine idles at 700 vs 600 rpm, makes it so different it's not even driveable.

Try building a few engines. Come back in 20 years when you have accomplished that, and let us know how they worked.

[Walter R. Malik]

If the tune is proper, what ever cam works in the intended usage of stock manifolds ect, the one that makes the most WOT power, will also run the best at part throttle.

The point is ... Power output at any throttle is NOT the main purpose for what this situation requires.

A cam which is around 235 @.050" might make a bit more power at 2,000 RPM wide open throttle than a cam with 220 @.050" but, will NOT have near the same amount of useful properties showing how the engine actually performs while going through a no wake zone or, pulling skiers out of the water or, simply cruising across the lake to a beach, concerned about how much fuel is being used. Power output is only ONE criteria which is to be considered and satisfied.
POWER output is not the "be all, end all" need for most applications yet those unknowing keep going there as if it is.

Yeah, Because an engine idles at 700 vs 600 rpm, makes it so different it's not even driveable.

Try building a few engines. Come back in 20 years when you have accomplished that, and let us know how they worked.

In 20 years I will be 87 years old; Been in this business for over 45 years and have built, (not simply assembled), probably over a 1,000 engines of just about any type imaginable. Not just one or two but, many champions and record holders in all walks of racing besides putting smiles on many faces of those who have nothing to do in racing.
I completed 5 just last month.

You have little clue here ...

[Fireonthemountain]

It just doesn't take much duration to romp and stomp and far less than the average person thinks. I was running a 234 intake and exhaust cam, in 455 on the street for years at 113 LSA, then noticed how fast a similar motor to mine was running with only a 214 and 230 at 112. So I then dropped down to a 222 and 230 at 110. Much more snappy and it can idle below 900, with less chop to the idle with less overlap and has higher vacuum. Much more fun in a car or a boat. Peak is almost meaningless in this game.

[CamKing]

We do a bunch of these. With that 4.25" stroke, this is what I recommend
226/236 @.050"
.335"/.335" Lobe Lift
114 LSA

[blykins]

The point is ... Power output at any throttle is NOT the main purpose for what this situation requires.

A cam which is around 235 @.050" might make a bit more power at 2,000 RPM wide open throttle than a cam with 220 @.050" but, will NOT have near the same amount of useful properties showing how the engine actually performs while going through a no wake zone or, pulling skiers out of the water or, simply cruising across the lake to a beach, concerned about how much fuel is being used. Power output is only ONE criteria which is to be considered and satisfied.
POWER output is not the "be all, end all" need for most applications yet those unknowing keep going there as if it is.

Yeah, Because an engine idles at 700 vs 600 rpm, makes it so different it's not even driveable.

Try building a few engines. Come back in 20 years when you have accomplished that, and let us know how they worked.

In 20 years I will be 87 years old; Been in this business for over 45 years and have built, (not simply assembled), probably over a 1,000 engines of just about any type imaginable. Not just one or two but, many champions and record holders in all walks of racing besides putting smiles on many faces of those who have nothing to do in racing.
I completed 5 just last month.

You have little clue here ...

Randy, he obviously has no clue anywhere.

I often wonder what causes people to act like they have absolutely no sense on an online forum. Is this guy a drunk? A druggie? Recently divorced? He is obviously very good at hiding behind a anonymous user name and casting insults at everyone else. An Internet troll has little credibility in anyone’s book.

[Warp Speed]

Evidently Mike Jones doesn't have a clue either, but that's ok because he uses his name?!? Lol

[CamKing]

Evidently Mike Jones doesn't have a clue either, but that's ok because he uses his name?!? Lol

I've got a bucked full of clues, I just forget where I put them.

IMO, this is something that has to be paid attention to.

Has factory Mercruiser log manifolds.

You really don't want to be sucking water back into the cylinders.

[andyf]

We do a bunch of these. With that 4.25" stroke, this is what I recommend
226/236 @.050"
.335"/.335" Lobe Lift
114 LSA

That looks like it would work pretty well. I just ran one of your cams in a pump gas 470 inch Mopar with a Holley Sniper fuel injection setup. Cam was 259/261 with 424/421 lobe lift. Worked pretty well, made 740 hp.

[Frankshaft]

We do a bunch of these. With that 4.25" stroke, this is what I recommend
226/236 @.050"
.335"/.335" Lobe Lift
114 LSA

That looks like it would work pretty well. I just ran one of your cams in a pump gas 470 inch Mopar with a Holley Sniper fuel injection setup. Cam was 259/261 with 424/421 lobe lift. Worked pretty well, made 740 hp.

The pump gas 470 I built my dad in 1997 made 740 hp. With a 258-258 at .050 solid roller. Indy S/R's with a crazy good ex port for the intake. The reason for the single pattern. Under carbed with an original h.p. 950, which was nothing more than a 750 main body with an 850 base.

[Warp Speed]

Evidently Mike Jones doesn't have a clue either, but that's ok because he uses his name?!? Lol

I've got a bucked full of clues, I just forget where I put them.

IMO, this is something that has to be paid attention to.

Has factory Mercruiser log manifolds.

You really don't want to be sucking water back into the cylinders.

That is the main limiting factor (and the outdrive). That will keep driveability way in check!
The rest is just tuning.

[Walter R. Malik]

We do a bunch of these. With that 4.25" stroke, this is what I recommend
226/236 @.050"
.335"/.335" Lobe Lift
114 LSA

That looks like it would work pretty well. I just ran one of your cams in a pump gas 470 inch Mopar with a Holley Sniper fuel injection setup. Cam was 259/261 with 424/421 lobe lift. Worked pretty well, made 740 hp.

That cam certainly would work well in that application. I have not used one of Mike's for that situation, is all.

I have used that particular 20110711 Lunati in at least 10 marine engines like THIS combination, (enough to memorize the part number), with great success and those good experiences with it, is why I recommended it.

There is a lot of boats from Lake St. Clair marinas running engines I have built; pretty much all makes and models, (cruisers to off-shores to ski boats to jet hydros), and I have made a few mistakes in the past to learn from.

"Good judgement comes from experience. And, experience ... well, that comes from bad judgement". Ben Franklin

[CamKing]

Evidently Mike Jones doesn't have a clue either, but that's ok because he uses his name?!? Lol

I've got a bucked full of clues, I just forget where I put them.

IMO, this is something that has to be paid attention to.

Has factory Mercruiser log manifolds.

You really don't want to be sucking water back into the cylinders.

That is the main limiting factor (and the outdrive). That will keep driveability way in check!
The rest is just tuning.

Another issue, can be the hull. Some of these hull designs get to a given MPH, and the more you try and run above that, the more the boat tries to bury the nose, and increases the drag. You've got some hull designs that a 100hp increase will only give you an extra 5mph. You can spend a schitload of money chasing a few HP. IMO, it's usually not worth it.