Procharger on 502

[Boatally Insane]

I have a 1993 230 Enforcer that I will be re-powering this winter. Currently the boat has a 330hp 454 in it and runs 59 mph (gps) at 4450 rpm with a 23 pitch revolution prop.

I purchased a 1995 502 magnum EFI that I will be rebuilding and installing along with a pro-charger but I can't decide which pro-charger kit to get. Is the 5psi M-1 going to be enough power for this boat (620 hp), or am I better off going to the 7 psi M-3 kit(700hp)? Would the M-3 kit give me better low to mid range power than the M-1 or would it just help me break the outdrive? Any ideas on prop size or top speed after the mods?


Thank you in advance,
Doug Schiller
Boatally Insane

 

[Boatally Insane]

I have a 1993 230 Enforcer that I will be re-powering this winter. Currently the boat has a 330hp 454 in it and runs 59 mph (gps) at 4450 rpm with a 23 pitch revolution prop.

I purchased a 1995 502 magnum EFI that I will be rebuilding and installing along with a pro-charger but I can't decide which pro-charger kit to get. Is the 5psi M-1 going to be enough power for this boat (620 hp), or am I better off going to the 7 psi M-3 kit(700hp)? Would the M-3 kit give me better low to mid range power than the M-1 or would it just help me break the outdrive? Any ideas on prop size or top speed after the mods?


Thank you in advance,
Doug Schiller
Boatally Insane

 

[mkhammer]

If you go with a 7 psi kit Yes you stand more of a chance to break a standard bravo drive. a xr drive will handle it just fine. since your rebuilding you should set your engine up with a blower engine in mind regardless of witch boost kit you choose. with a 5psi kit you will run about 80mph+ and can turn a 28 pitch prop W/ 1.50 ratio. I'm running a M3 on my hp 500 carb at 8 psi at 5400 rpm with engine mods and a 1.50 xr drive spinning a 30p bravo1 prop at 93 mph on gps. I'm changing my lower case this winter and trying a 32p bravo1. Overboard has a 454 efi w/ a 5 psi kit and runs 80 mph. I beleave he running a 28p bravo1 prop I can't speak for him but he could give you good advice on a simular setup.

 

[mkhammer]

To go fast cost alot of money. If you want to go the speeds a procharger or any supercharger can put you at. you need to consider more than just your drive to be safe. steering is very important. external steering and a hydraulic helm,billitt trim tabs. I would recommend. offshore mounts. fuel preasure , boost and pyrometer gages. with a 5psi kit you can get by with less.

 

[Boatally Insane]

I had planned to go to full hydraulic steering this summer, I already have trim tabs but they're only single ram insta-trims so I'll have to upgrade those. I will probably just go with the 5 psi kit, if I get into the 80 mph range that will be fast enough for this boat. I was going to install boost and fuel pressure gauges, Do you think I'll need a pyrometer with the 5 psi kit? When I rebuild the engine I am probably going to go with J&E pistons (is't already bored .030 over) I'm not quite sure what cam yet but I will probably stay close to stock so the fuel injection will work properly. I'm buying the pro-charger from a dealer in IL who also sends the computer out to be tweaked a little for the blower. They raise the rev limiter some and change the temp for the cold start enrichment so the engine won't be running too rich all the time because of the cooler engine temps with the crossover. Should be a LOT more fun next summer!!!


Doug Schiller

 

[mkhammer]

A pyrometer is important it tells if you have a problem right away. If your lean it will save your engine. If your running rich it will read cold. you don't want your exhaust temp over 1450 degrees at WOT. The rest sounds like a good plan to me. Also run a sea strainer you don't want a bunch of junk going through your inner cooler. You should pick a cam on a 112 lobe center W a lift and duration sutible for your setup. iconel valves and stainless core marine head gaskets. Run headers. and you shoudn't have any problems.

 

[John B]

MK Hammer is right on the money. I have a 91 Maxxum 28' with a new Mercury 454mag MPI, M3 Pro-Charger 5lbs boost with intercooler, CMI headers, and new bravo one drive. The boat went from mid 60's to 83 mph, turning a Bravo1 28p prop. I also have a deluxe cabin (sink, fridge, stove, porta potty) I'm very happy with the performance and reliability of this set up. There are some pictures of my boat & motor in the "Picture This" section. My boat is larger & heavier, but I had great results. Good Luck!

 

[over board]

MK is right.
I have a 253 w/a 454mag efi, an m-1sc pro-charger, gil exhaust, iconel exhaust valves, fel-pro marine head gaskets, arp head bolts. I like the sc (self contained) because of the fact it has its own oil supply. I run a 28 hydromotive quad-4X This is simular to bravo 1, I have not really went for top spd. yet (the wife gets nervious)

but so far I'v seen 80 @ around 5200 rpms.
If you go with a m-3 you will need more front engine clearance than with a M-1, also bigger injectors, but you would be able to run 89 octane w/ 5lbs of boost or @7lbs you would need 91.
I would get the 3 gauges MK suggests, plus one more. The electric fuel press. gauges are not known for thier accuracy so I put a summit racing 1 1/2" liquid filled in. I ran a T at my fuel press regulator so both gauges were reading from the same place. My electric gauge can read as low as 10 psi witch made me very nervious but the mecanical summit gauge will show 30 psi. at the same time. Good luck next summer should be lots of fun for you.

 

[Boatally Insane]

I've been shopping around for hydraulic steering, but have not found anything I'm satisfied with yet. Are there any systems out there less than $4000.00? Would the add-on system be adequate or just a waste of money? Also how big of trim tab do I really need?


Thanks,

Doug

 

[mkhammer]

Full hydraulic system arn't cheap my zieger helm alown was $1,100. without a steering wheel. I don't know of any systems under $4,000.00 Mine said and done was closer to 5k I used WPM twin external steering rams,zieger tilt helm, all other parts charlon pump, hose and fitting and filter I bought from IMco. A tie in system with external steering will help but there is no comparison to a system with a full hydraulic helm. you will still have play in the system with the stock teleflex cable and stock mercruiser stering accuator. full hydraulic there is no play. I did all the labor my self and saved some money there. If you have a shop Install your system you may pay close to7k to have it done. note: a IMCO helm did not work on my convincor the dash is molded for a 4-1/4" base the IMCO tilt base is much wider. the zieger helm was perfect size. There was problems with the dash thickness and clearancing behind the dash, I had to machine 1/4" off the helm spacer that goes behind the dash and carfully surface the fiberglass behind the dash mounting surface to abtain a true seat for the charlon accuator. also clearancing for the back of the accuator. It was time consuming and alot of pre fitting went on. the transom side was a piece of cake. It took me about a week to finish it. Night and day differance, my steering is awsome.If you plan on doing about 75 or 80 mph a tie in system would help any faster you better go all the way.