1st Post, Want more speed.. HELP

[Racing Ray]

Mike
No problem on the questions. You just like myself want to be sure you do it once and right. The cam I reccomended is used in literally hundreds of boats. The centerline is specfically chosen for the cylinder pressure and use in conjunction with lower compression ratios. It will build most power in the 2000- 6000 RPM range. Crane recommends this cam as a marine performance cam.
You can idle all day long without loading up or run it 5100 RPM under load. The best site on the internet for information on making serious power with Mercrusier/Bravo set-up is Offshoreonly.com
The best in the business post there and you will see the cam I mentioned and the next larger one are recommended 10:1.
You have a MarkV block so you will need the retro-fit roller lifter that includes the vertical locking bar. These are very expensive if you look at my list. There are lots of cams that will make power and work for you.
You can save a lot of money with a different choice but you can not get a better cam. I don't like the next bigger cam as you will pick up some top end speed but sacrifice some on planing time and if you pull skiers you will notice it.

[Chillin The Most]

Originally posted by Racing Ray:
Mike
No problem on the questions. You just like myself want to be sure you do it once and right. The cam I reccomended is used in literally hundreds of boats. The centerline is specfically chosen for the cylinder pressure and use in conjunction with lower compression ratios. It will build most power in the 2000- 6000 RPM range. Crane recommends this cam as a marine performance cam.
You can idle all day long without loading up or run it 5100 RPM under load. The best site on the internet for information on making serious power with Mercrusier/Bravo set-up is Offshoreonly.com
The best in the business post there and you will see the cam I mentioned and the next larger one are recommended 10:1.
You have a MarkV block so you will need the retro-fit roller lifter that includes the vertical locking bar. These are very expensive if you look at my list. There are lots of cams that will make power and work for you.
You can save a lot of money with a different choice but you can not get a better cam. I don't like the next bigger cam as you will pick up some top end speed but sacrifice some on planing time and if you pull skiers you will notice it.
Ray,
Thanks Again! By the way I don't pull skiers anymore. Can't stand going that slow.

[Snafu]

The number for Big Block Marine Performance book is.626-6753548. Dennis Moore will usually answer the line and he will answer some questions over the phone. This book is one you can't put down!!! If the terms Quench and scavenge are not in your every day gear head conversation this is a must!!!
Chillin
There is about 10 pages on cam selection. Reversion is a major concern in your selection!!!
Can you find out what your 236 did before the S-jack??? Thanks Rinker Dudes

[BOFH]

The choice in cam is where do you want your power. Low end power means busting out on plane faster. High end power means more top speed. This can be overcome with prop selection, but your will have loading up problems with a long cam.
Heads are nice. The new marinized alluminim ones from Edlebrock look promising, and save a bunch of weight.
As to compression, you have too look at a few things here. High compression means power, and fuel economy, with potential detonation. Low compression means cheap gas, and less power. Two ways to combat detonation are thremal barrier coatings and water injection. Both cool hot spots which lead to detonation. I have run 12.5 to 1 on pump gas with water injection. Both of these systems are hard to find, however. Expertise on them is even harder to find.
Valves. Big is good, but look out for shrouding. If you go with big valves, they can get so close to the cylinder wall that they flow less than smaller valves. Also, high lift can cause a piston to slap a valve. Good builders have play dough in there tool box. Ask why... If they don't answer, get a new engine builder.
As to the carb, if you just want to spend the money, go with fuel injection. A laptop is easier to work than a jet kit. :-) You will have to modiffy the headers for the sensor before the water is injected. Good power gain, and a lot of economy.

[Chillin The Most]

Originally posted by Snafu:
The number for Big Block Marine Performance book is.626-6753548. Dennis Moore will usually answer the line and he will answer some questions over the phone. This book is one you can't put down!!! If the terms Quench and scavenge are not in your every day gear head conversation this is a must!!!
Chillin
There is about 10 pages on cam selection. Reversion is a major concern in your selection!!!
Can you find out what your 236 did before the S-jack??? Thanks Rinker Dudes Snafu,
The original owner says 58 mph with the 21 SS Mirage, with S-Jack 63mph,S-Jack and 23SS Mirage 68MPH.I've never had a 23 on it. A buddy of mine has a 23 and a 25.
When I get my boat out of storage in Mid-April, I'm going straight to the water with that 23 and 25 and see what I get. I think the 25 is just going to slow me down in mph and less RPM. I'm really curious to see if that engine still has enough torque to turn that 23 and give me 5 more mph though.

[Chillin The Most]

Originally posted by BOFH:
The choice in cam is where do you want your power. Low end power means busting out on plane faster. High end power means more top speed. This can be overcome with prop selection, but your will have loading up problems with a long cam.
Heads are nice. The new marinized alluminim ones from Edlebrock look promising, and save a bunch of weight.
As to compression, you have too look at a few things here. High compression means power, and fuel economy, with potential detonation. Low compression means cheap gas, and less power. Two ways to combat detonation are thremal barrier coatings and water injection. Both cool hot spots which lead to detonation. I have run 12.5 to 1 on pump gas with water injection. Both of these systems are hard to find, however. Expertise on them is even harder to find.
Valves. Big is good, but look out for shrouding. If you go with big valves, they can get so close to the cylinder wall that they flow less than smaller valves. Also, high lift can cause a piston to slap a valve. Good builders have play dough in there tool box. Ask why... If they don't answer, get a new engine builder.
As to the carb, if you just want to spend the money, go with fuel injection. A laptop is easier to work than a jet kit. :-) You will have to modiffy the headers for the sensor before the water is injected. Good power gain, and a lot of economy.
BOFH,
Where I want my power is... I want to come out of the hole at a preety good rate and still have a good top end around 75mph. I might have to play around with the 23 and 25 prop to see which is going to work the best.
Here is just a theory >>> Two boats that have about the same top end speed, say 73-75 mph. Boat #1 comes out of the hole much quicker than boat #2. Boat #1 now has a 1-2 second lead over boat #2. Now boat #2 has to play catch up, they reach top speeds of 73-75 mph. Boat #2 now is still behind by 1/2 to 1 second.Everyone one on shore says wow boat #1 is a much faster boat than #2, not knowing they are doing the same speed.
That is why I want it both ways. If someeone takes me out of the hole, I still want that torque to catch them before they get to much of a jump on me.
Did you read Rays earlier posts on cams, heads, and all the other add ons? If so tell me what you think.
EFI is not in my future. If I want to build this motor, then ad EFI, I might as well by one of those crate 502 EFI, 500 hp and go from their.

[Snafu]

Thanks For the info Chillin!
Spoke with Rinker...They said 236 is a little faster hull than 232. I am doing 58 by Radar with 21 Mirage 385 HP. 4850 rpm With my 232.
He said there were about 20 1995 236's. They were actually built in 1994 but were stamped 1995.
Can you hit trailer button all the way up with the S-Jack not hitting swim platform??
Can't wait for the weather to break!

[Racing Ray]

Chillin
Give you an example of out of the hole. My son borrowed my boat for a couple of hours last night.
A 21 foot Carrea pulled along side him equipped with a 454 and jet drive the other fellow was by himself my son had 6 adults and 2 kids in my boat.
Jets are best known for the out of the hole performance my son owns a real fast one himself. So he is thinking he is going to get waxed on the start. They were coming out of a no wake zone.
He told me today how suprized he was the jet had him by 1/2 a boat length until they were planed and he was about 3 boats ahead by the time he was trimmed out and had only reached about 60. Thats what a 4 blade prop can do for you. Thats what you get when you pick the right cam.

[Chillin The Most]

Originally posted by Snafu:
Thanks For the info Chillin!
Spoke with Rinker...They said 236 is a little faster hull than 232. I am doing 58 by Radar with 21 Mirage 385 HP. 4850 rpm With my 232.
He said there were about 20 1995 236's. They were actually built in 1994 but were stamped 1995.
Can you hit trailer button all the way up with the S-Jack not hitting swim platform??
Can't wait for the weather to break!Snafu,
It doesn't hit when all the way up. If I were you I would borrow a 23 Mirage and see what you get. Probably a little slower out of the hole, not that much though, but I bet you still have the torque to see maybe 61 to 63. RPMs will be down a little but who cares , sounds to me like you just want more speed anyway. Try the 23, hell you got 75 more HP than me. You must have the EFI motor.
MIKE

[Chillin The Most]

Originally posted by Racing Ray:
Chillin
Give you an example of out of the hole. My son borrowed my boat for a couple of hours last night.
A 21 foot Carrea pulled along side him equipped with a 454 and jet drive the other fellow was by himself my son had 6 adults and 2 kids in my boat.
Jets are best known for the out of the hole performance my son owns a real fast one himself. So he is thinking he is going to get waxed on the start. They were coming out of a no wake zone.
He told me today how suprized he was the jet had him by 1/2 a boat length until they were planed and he was about 3 boats ahead by the time he was trimmed out and had only reached about 60. Thats what a 4 blade prop can do for you. Thats what you get when you pick the right cam.Hi Ray,
Once again, thanks for the information. That's exactly what I want, I really don't care If someone takes me out of the hole, but when that GRUNT TORQUE starts working thats when I want this thing to pick up and go.
Afterall most of my raceing is when I'm just putin along at 40-45 mph and someone comes up along side and wants to throttle down and go.(Ok everyone, along side means at least 100 ft.to the side. Safety First)
Later,
Mike