Quad rotor setups...

[fourspeednup]

I'm looking for any info (pun intended) on the whipple quad rotors, or any other manufacturer for that matter, and the advantages over one large/ overdriven blower.
I was talking cars with a friend and since he knows I like boats he asked about the "dual blower" trend out at the river. I started to give a BS answer but really had no idea. Any info would be appreciated, or if you could point me to a previous thread that'd be cool.

[Infomaniac]

Here you go. All of the discusion you would ever need.
Info builds slug engines thread (http://www.***boat.com/forums/showth...threadid=35016)

[fourspeednup]

Thanks info,
took awhile to read between the crap but real good stuff in there.
That's one hell of a slug

[HighRoller]

I'm lost. HeavyBoat said his engine made over 1000hp on the dyno. But it only made 704hp at the rear wheels? Sounds like either he's lyin or his Fairlane gots sum driveline issues!! But I'm sure he'll come up with a good excuse and probably flame me after he does.

[HEAVYBOAT]

Originally posted by HighRoller
I'm lost. HeavyBoat said his engine made over 1000hp on the dyno. But it only made 704hp at the rear wheels? Sounds like either he's lyin or his Fairlane gots sum driveline issues!! But I'm sure he'll come up with a good excuse and probably flame me after he does.
High roller, you will see no flaming .... I’m on probation, and I still get threatening emails about my squirt gun tactics.
Good Excuses? Lyin?? Dam highroller!! Time to fill us in, share the wealth. What did the hotrod magazines tell you to use for drivetrain losses? You know what, dont even bother answering.. lets just work with real world scenarios.
I haven’t made 4 digits as of yet, and I don’t know where you got 1000hp.The best pull was just under 950 hp.
Drive train losses using an automatic transmission, (on an accurate chassis dyno) range anywhere from 20 to 30 percent. Actually a friend of mine owns a Mustang MD250, which is one of the best chassis dyno's on the market today. Here’s a quote off his website.
http://www.dynomotive.ca/
“My automatic equipped vehicle is showing very low HP numbers....why? “
Automatic transmission and non lock-up torque converters "use" a lot of power! We are finding anywhere from 15 to 25% less power then a vehicle with a similar engine but with a standard transmission. Superflow did a test in fact where they put a motor on an engine dyno, and then put it in a car and did a rear wheel horsepower test with an auto trans, and non lock-up converter, and lost 26% of their power!
Now if we take my numbers, 950 fwhp and 704 wrhp that calculates to 26% loss. Go figure... LIES ALL LIES
But don’t get me wrong, I’m not happy with the stats,its far from an efficient combo and I would like to see less loss, but like I said on that thread...... I’m using a heavy power suckin Ford C6. I’ve changed converters this winter, and I’m hoping that will tighten it up a bit.
R.

[HEAVYBOAT]

information on the MD 250
http://www.ap-engineering.com/dyno.html
http://www.mustangdyne.com/
The advantages of testing on a dynamometer with an absorber (MD-250) compared to inertia type dynamometer are many. The key advantage is, on the MD-250 the dynamometer controls the vehicle. This allows for step and timed sweep testing. On an inertia type dyno, the vehicle controls the rotation of the drum, resulting in an inability to perform step testing or have control of sweep testing. This Dyno measures actual torque, not "calculated" horsepower from the acceleration of a big drum.The only problem we have with this dyno, is trying to educate all the magazine (hotrod) readers on why the Hp numbers seem so low.

[DogHouse]

Originally posted by fourspeednup
I'm looking for any info (pun intended) on the whipple quad rotors, or any other manufacturer for that matter, and the advantages over one large/ overdriven blower.
The quad rotor advantage is that the screw compressors are much more efficient than the roots, not that there's two of them. One single screw compressor that is the right size for the motor would be more efficient than using two smaller units, but so far nobody is making one the right size (that I've seen). Two of the small Whipples just happen to work out well for a lot of 900+ hp gas applications. I guess it's cheaper to make a new manifold and belt setup than design/tool a whole new blower. All that hardware looks trick too.

[DORIGHT]

HeavyBoat
704 at the rear wheels? I aint getting in that thing!
Unless IM driving,
Drive train losses are no fun but they should be expected and are understood by the more experienced.