Reply With QuoteWhipple all the way. Conventional blowers are not as efficient and heat up the charge too much and take up too much room. Prochargers lack lower end torque.
I was having a conversation with a friend of mine and he says, "Everyone uses a blower and it is much better then a supercharger". I want peoples thoughts on the subject. I would like to build a motor to 800hp and wonder which is the better way to go and why.
cougar27mtr
Whipple all the way. Conventional blowers are not as efficient and heat up the charge too much and take up too much room. Prochargers lack lower end torque.
that is true that prochargers do lack the same low end as whipple, but if you are running a drive like bravo 1 it is much nicer to your drive. prochargers produce great mid range as well as top end. they are easy to install, have great intercoolers, and are easy to work on. i am in no way knocking the whipple, i do hear great things about them also. just my 2 cents. good luck with whatever you do, but i would agree with rivercrazy that conventional blowers are not the way to go. do your research on both the procharger and whipple and decide what is best for you.
Ok so the votes are in favor of the supercharger. Now with all this knowlege out here I need to know what I should do. I want to build the motor from scratch. What parts should I buy or who should I let build this motor for me...
cougar27mtr
They all have their pro's and cons. But lets get some terminology going:
Super chargers are typically "roots" type blowers that respond to wide open throttle.
Whipple chargers are "compressor" style blowers, and also respond to wide open throttle, but don't typically move as much air as a "roots" style (especially 871's and bigger), but are much more low profile.
Pro Chargers are "centrifugal" and respond at higher RPM in much the same way a Turbo responds.
Pro Chargers are easier on outdrives as a rule, but they can definitely be set up to trash a #5.
I currently have a 671 blower in my little flat bottom. But, if I were to set up anything with an engine cover, I would definitely go for a Whipple or Pro Charger.
My Father has a 25' river cruiser with a Whipple 3.2 liter with intercooler and injection. It dyno'd at 840 HP and runs on 91 (with Prolong Octane additive). It is a total sleeper with the flat factory engine cover - he did have to provide additional intake air on the sides of the seats.
Cougar27MTR
if your in So Cal, Call Jim Wilkes at 714-540-8908. If no in So Cal, Call Jim for a reference in your area.
Just to clear things up a little, they're all "blowers", "superchargers", and "compressors". "Roots", "screw", and "centrifugal" are all just different types of mechanical devices that take energy off the crankshaft and use it to compress the air that is going into the engine. Roots and screw blowers provide similar boost curves, i.e. relatively flat with rpm, but the screw blowers achieve that boost more efficiently (less heat, less power required to drive) than roots blowers. Centrifugals start out with low boost levels at low rpm and then climb significantly with increasing rpm. They are like turbos in that they use a centrifugal compressor section, but their boost curve characteristics are quite different. Turbo systems can be set up to make plenty of boost at low rpm.
-brian
i went through your same dilemma 4 years ago.i had a i had a 26ft american offshore with a 454 mag.my buddy had the same boat with a 502mag.i put on a 871 littlefeild and he put on a pro charger with a 5 pound pulley.i loved my set up but his rig had a hard hard time off out of the hole but hauled ass on the top but no faster than mine.i could always change boost easy with a pulley change he went to the 7 pound puley but was always bouncing it on the limiter,so he would put on a different prop but the boat wouldn't even get on plane.i could mash my set up and it would jump right up with the same prop set up.so what am i rambling about i guess it depends what you have as to what would be your best combination,if it a 26ft cat 871 all the way.
A little help.
I have a 26 American Offshore, 454 mag. w/ a Procharger. Now: new heads, cam, intake, carb, MSD ignition. I have been running 7 lbs boost for 250hrs. I really don't think the motor would last this long with a roots blower (871) at 7 lbs. Maybe 4-5 lbs. My boat planes fine with a normal load and turns 5100rpm.
Boatnam2 has a point. If I have 5 brawley dudes in the boat it does take a while to plane. Every set-up is different. Maybe his friend still had stock ignition (initial timing 6 deg.). That will rob you of torque on bottom end with a low compression engine.
Bottom line. 871(power everywhere) Procharger (less bottom,more boost/power, less heat) Whipple (maybe middle of the road) Intercooler a must. Just my 2 cents.
[ July 20, 2002, 12:05 AM: Message edited by: FASTERDAMITT ]
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