Re: New Guy with Questions
 

tripps, that was a real nice area you stayed in, are they condos or time share ???

Re: New Guy with Questions
 

Thanks again for all the info.
It looks like I will be making the cam change before next season. I will probably only run it to about 5000rpm. I was told by a local builder and Mercury Support Line that I had the same heads as the 525sc. So CAM, Lifters, Springs, Roller Rockers, Carb, 4 hole spacer, gaskets, ignition,..... is their anything else I am missing? (Probably a Prop)

It is amazing how much more torque this cam makes in this engine. (ran the numbers through Dyno 2000)

Thanks again, I do appreciate the help.

Re: New Guy with Questions
 

What cam are you going with?
No need to change the ignition if your limiting yourself to 5000rpm.
Also, no need to change the carb if your going to stop her at 5000rpm; just re-jet the 750 Carter to the 390HP/502 specs.
You may already have a 4hole spacer; have a look.
Yes, your 454mag has the same head castings as the 525SC, but the heads have smaller valves (2.19/1.88 vs 2.25/1.9). Don't change them though; too much $$.
I would add a high flow spark arrestor to your list, K&N maybe...
I like your plan Razor; the 50HP bump will net you 4-5mph...

Re: New Guy with Questions
 

Already have the spark arrestor, I am going with the 525sc Cam, just not going to run it all the way. I will get the MSD ignition and set it at 5,200rpm. Do you think I will be able to turn a 26" Hydro P5?

Re: New Guy with Questions
 

Great choise for a new cam. Most people that build a "330 on Roids" use that cam. I've seen dyno results between 460HP and 500HP depending upon the other work done to the engine. Between the cam change and good exhaust your engine will make at least 60HP more than a stock 454Mag... :D
Do you know were the rev limiter is set on your Merc Ignition?
Some say 5050 some 5200, I've not gotten a straight answer. I do know that my engine will rev to 5200.
Are you just adding the MSD box to your existing ignition or replacing everything? The MSD add on box will help with idling and cold starts. But if you go with the complete MSD ignition, just know that it is not anywhere near as reliable as the Merc thunderbolt.
As for as the Hydro prop, I was told to try a 25p P5X first, but like you, I was thinking 26p. I'm not going to spend the $$ on a 5 blade though; it is a great choice for you beeing that you need a new prop anyhow...

Re: New Guy with Questions
 

?? So, I may not need the Ignition? (if is already at 5200) What about a hotter coil? How hard was it to change the cam while it was in the boat? I do not have the facilities to pull the engine. I should not have a problem doing the springs and rockers, I will just pull them off an do them. Do you have any recommendations on the Roller Rockers? (are they needed with such a low rpm)

I heard the Hydro P5X was 1" more than a bravo at the same pitch. Thus, with the extra drag of the 5th blade and the added 1" of pitch, I would think the 26" Hydro P5X and a 26" Bravo1 would have about the same top speed. With the Hydro giving more low end power, high end stability and running smother.

I will keep my 24" Bravo1 for when my friends want to go tubing and such.

Re: New Guy with Questions
 

Razor,
If the rev limiter is 5200rpm, I would not change the ignition to a full MSD system or any other brand. Ask over on the Tech forum if you need an ignition change. I would save your money for a new prop... :D
Yes, you can change the cam in the boat. When your ready, we should talk on the phone, way too much typing.. :rolleyes:
Bravo 1 props tend to measure low on pitch, ie a 28p is truly about 27.25". When going from a B1 to a 5 blade I would say two sizes smaller. I run a 28p B1 so I would try a 26p 5blade.
T-mone is the only guy I know running a P5X on a 24' hull like ours. He runs a 25p at like 5700rpm in the mid 80s with a 585HP/502 for power in his 24' Pantera... :drink:

Re: New Guy with Questions
 

Wow,
1.5gear, 25pitch, 5700rpm, 83mph = 8% slip
if I can turn the same prop 5000rpm with the same slip I should see 73mph and 75mph if I can turn it to 5200rpm. I think my engine after a cam change should be able to turn it to 5000rpm, what do you think?

I had an MSD (DIS) on a 98 Mustang and it ended up failing.......I was not impressed......

Re: New Guy with Questions
 

Yes Razor, with a 5 blade the slip would be less than a Bravo 1. I see 11-12% with my boat spinning a B1.

A straight V 24' Super with a stock 454mag running light will go 73mph at 5000rpm spinning a 25p Mirage plus 3 blade; 1-2mph slower with a 26p Bravo 1.
Your boat should run 75+mph with the hotter cam and better exhaust... :D
24' Superboats are typically a little faster than 24' Panteras with the same power, but neither of us is going to catch T-Mone... :drink:

I missed one of your other questions:
Gen V and Gen VI BBC have a non-adjustable rocker setup from the factory. You will need to change to an adjustable system when you change the cam. I would suggest Crane gold or Comp Cam magnum roller rockers and Comp Cam conversion studs.

Re: New Guy with Questions
 

superbabi,they are timeshares,you can rent or buy thru starwood. Rci has them too but not at harborside. I know of one for rent there ,let me know sasp if you are intrested in one before i give it up :eek: :eek: :eek: I switched from oct to nov cause of the nice days here on LI and the Hotty totty run call me 917 468 3607 tripps