Blown or NA?
 

Ok, this question is for reliability and fuel consumption purposes only and not the cool factor....

If you had a pair of 800 SC's (572 ci.) and wanted to detune them to say 675-700 HP to get more reliability and better fuel consumption would you;

1. Remove the blowers and sell them, change pistons, change cams, single plane intake, Dominator carb etc.
2. Keep the blowers and turn down the boost and re-jet the carbs. Currently boost is set at 4.5 lbs

At what point does it take more power to turn the blower on low boost than it does to run NA?

My engine builder wants me to keep the blowers, he thinks I will love the torque curve, but I'm affraid of the torque on the IMCO Extreme SC's. Torque is above 720 lbs from 4000 rpms to 6000 rpms with a max of 780 at 4750. Max HP is 795 at 5800 rpms.

Thanks,

Panther

Re: Blown or NA?
 

I understand your concern about drives and reliability,i don't know about your particular application but my boat actually went from 1.2-1.5 mpg cruising to about 2 mpg cruising by adding supercharger and taller props. I guess how you drive your boat and the weight would determine how long those sc drives would last,they should be close in durability to my max machine works drive,i drive stupid sometimes(w/o holeshots from 2500 rpm's)and i have about the same power in a single v.drives break about every 100-150 hours,if i was a little easier on it they might last 200-300,Smitty

Re: Blown or NA?
 

I think it you remove the blowers you will be unhappy with the boat. At 4.5 lbs of boost you are turned down already.

I would go with your tag line "If it ain't broke, don't fix it!"

Re: Blown or NA?
 

One motor needs a new cam so I am going to rebuild both.

Re: Blown or NA?
 

I guess no one else knows?

Re: Blown or NA?
 

I Totaly Agree Leave The Blowers You Won't Regret It Maybe Take Some Cam Out Of It And Drop Comp A Bit You Should Make The Power No Problem And You'll Still Have The Big Torque To Turn The Props. I Use Some Small Hydraulic Rollers In My Packages That Have Gone 300hrs With No Valve Spring Maintanance And They Make Good Power Easy On The Parts.sincerely Laz Mesa

Re: Blown or NA?
 

A guy who does my boat work in St Pete told me he was taking the blowers off his boat. I asked him why,and he said he was tired of pouring all the gas through it.

Re: Blown or NA?
 

Thanks, I'll keep that in mind. If you have some cam specs please forward them to me and I will compare them with what is in the motor when I get it appart.

What about lowering the boost to 2-3 lbs??

Re: Blown or NA?
 

I know!!! With (4) 850 holleys, I was thinking the same thing... I've got some tough decisions to make...........

Re: Blown or NA?
 

Are you speaking of the Merc 800SC's ??? I you are, I know of someone who bought some Merc 800SC's years ago. He said he was personally told by Fred Kiekhaffer that they actually only make about 730hp to begin with anyway. :rolleyes: