JRider

iTrader: (1)

This past summer I picked up a 2001 Profile cat with 575sci and Bravo XR drive. I am very impressed with the performance for a single in a boat of that size. I plan on changing the head gaskets out to cometics but...while im in this deep I am thinking cam change. What would be a good off the shelf grind for this motor? I was thinking of the crane 741??? Is there a better cam for a supercharger motor? Any suggestionw would be great.

The mill has 200hrs on it. Is there anything else in the upper end that should be checked out while apart? I plan on having the blower checked by Darin Meyers rite here in MI.

I am also on the verge of cranking up the boost. The question here is what path do I take???

Option 1
I could do the AZM boost kit.

Option 2
Buy a smaller pulley, A1000 fuel pump + regulator, change the 140 thermistat to 120 and go with MSD ignition.

Option 3
Try to sqeeze a whipple intercooler under the hatch along with the pulley and MSD.

Option 4
Add a superchiller and modify or replace the hatch along with the pulley and MSD.

Anybody have any suggestions appreciated.

BillR

1st. You should have Blower Shop rebuild and update the bower before you do any of the above.

JRider

iTrader: (1)

I will not be using the Blower Shop but the blower is going in to Darin Meyers here in MI. I know the back bearings are a problem on these.

Steve Zuckerman

Used them both. I prefer DMPE for quick turnaround, service, pricing, and less frieght. Not a knock on TBS. Just bought a new billet 871 from them. Their emphasis seems to be new product sales VS service on "other" manufacturer's blowers.
Jeb, you can also pick up some efficiency by having your 256 teflon stripped at DMPE. It is not from the factory.
I would try the AZSM boost kit for starters, and rebulid your blower. See how that does. If you need more, an intercooler is an easy mod. With the cold water you have in MI, I think it would help a LOT. You will lose a little boost with the intercooler, and can then go to a 3" or 3.25" pulley. 4" is stock, 3.5" comes with the AZSM kit.
When you have your heads off, have them checked out by a good performance shop. The cam can be upgraded, but with that low 7.5 compression ratio, it may not help that much. I regulary turned my stock cam 5500 with no problems. I would wait until you can upgrade to 8.5/8.75 CR, and then add the cam. The stock cam is a flat tappet, so a 731 or 741 or Merc 525 hydraulic roller is a nice upgrade.
Regards,
Steve

JRider

iTrader: (1)

Hey Steve,
Was going to PM you on some of this since you have been thru it. The blower will definately be getting a good treatment. As far as the AZSM boost kit I know they raise the rev limiter but what else do they do??? I believe someone has been in the ECM as I can wind 5500. I may be wrong but I think the kit might be a little overpriced for the goods. The parts are less than $500??? For the given HP gain maybe it isnt that bad. Anyway, I would love to intercool it but the reality is I am not sure of the space as of yet. I will have to get some clay and go measure it in storage. I think it would definately help in hotter weather.

Steve Zuckerman

Jeb,
The Whipple is 1 5/8" taller than stock. Most of the "bolt between" models are around 4"s.
The W256 will make some boost, but it starts getting less efficient the faster you turn it, making more heat. That's where the intercoolers come in. Our water starts out cool in the spring (60s), but gets bathtub warm (80/90s) in the summer. I think you would defnitely benefit with IC with the cooler water in your neighborhood.
If you are turning 5500 (have you checked your tach against a Merc/Rinda tool or shop tach for accuracy?), your ECU has been modified. My stock ECU would rev limit @ 5300.
Regards,
Steve

JRider

iTrader: (1)

Thanks for your feedback Steve. I like the low-profile whipple but it may not be low enough. If I have to modify or replace the hatch I will most likely do the Superchiller...just need to get into storage and take some measurements. The HP loss in warm water on warm days was VERY noticable.

Do you know what else AZSM does to the ECM other than the rev limit?

ciaoderhead

I'm in the process of installing the Whipple kit now on my '02 TopGun. Didn't want to modify the engine hatch. Only 100 hours on the boat but I found some signs of the intake gasket failing at the rear water passages. Thinking now I better go ahead and change the head gaskets while I'm in there. If I go that far guess I should go with new valve springs especially since the Whipple Kit reprograms the ECM and raises the rev limiter.

The quality of the Whipple kit is really good. A few items were missing but Dustin and his guys took care of it imediately. Dustin follows up and is very reponsive to questions. THANKS DUSTIN

Blowers are going for a freshining too.
Am I missing anything else?

BillR

How much HP gain do you get from the:
3.5" Pully
3" Pulley

I have both, but haven't tried them yet.

ciaoderhead

Bill,
Are you running intercoolers?

When I got my boat it had the 3.5 pulleys and the GPS recall had 95 on it (probably a strong current and tailwind that day). I went back to the stock pulleys and have only run a best of 89 but can't turn above 5000rpm. Thinking the intercoolers will wake it up and work with my props. The Whipple kit comes with a 3.25" pulley.