josh19wrc

IHI built, Lysholm Screw type supercharger. Got her for $150 bucks. Comes on the Mercury Verado 2.6L inline 6 cylinder outboard boat motor. Around $2300 bucks new. Slightly used, but, in good working shape. A few nicks on the rotors, but, nothing too serious. Ignore the rotors being wet, I sprayed cleaner in it to get some dirt out of it and they weren't dry yet. Moves 105 CID/rev, max RPM of 14K. Do the math, geared at 2.25:1, it will move 1,470,000 Cubic In/min. A 360 at 6K RPM sucks 1,080,000 CI/Min, which, will generate a presure ratio of 1.36:1, or, about 6 PSI of boost... Thats not much, BUT:

It's gonna look great mounted to the side of the 360 CID V8 in the Power wagon: being fed by two HX35's....

90CRXSiR

never knew outboards came f/i.

HiProfile

Quick question - why would you want to compound the efficiency losses of two types of compressors in a serial/sequential setup? As efficient as they are, you're still taking air that's been through a 78% efficient turbo, and putting it through another 80% efficient process, at best. That ends up as 62% efficient. You also use power to spin those rotors, which use more than a roots-style blower.

Be a man and go with just two blowers or two turbos in parallel.

josh19wrc

Bacause two HX35's wont spool on a 360 until 2700 RPM, so, the super will come in right off idle and feed the engine until thw holsets come up, then, the super compresses the holset boost another 3-5 PSI, which, will raise the intake charge pressure above the exhaust manifold pressure, which, will let me run more cam duration and valve overlap, which, will let me completely clear the combustion chambers, as opposed to your typical turbo engine, which, has little to no valve overlap. What happens is the exhaust never leaves the chambers, and superheats the head. You can't run any valve overlap, as the exhaust will backfeed due to the pressure differential. In a 360 V8, thats 72cc's per chamber, times 8. Thats 576cc, or, about 33 CID I loose due to cam timing, as well as the added efficiency of longer duration cam timing. So, yes, you're right, Im compounding efficiency losses, but, the offset in power gained though cam duration, timing, and full cylinder filling will offset. That, and, its really ------ cool to have 3 blowers under the hood of your 60 year old military truck.

CspecRun

Cool ----, never seen one of those before...Sounds like an awesome project as well...

crx2211

I want one of those outboards for my boat!

bitchM0VE

He knows. Good luck with the build. FWIW-that SC won't just add PSI. It will multiply the density of the air going in. So you feed it 20 PSIG (atmospheric of 14.7 PSI plus boost 5.3 PSI), and it's pulleyed to move 1.5x as much air as the engine ask for on its own, assume 90% adiabatic efficiency, then you're looking at a 7 PSI gain. With big pressure ratio's on the SC the final boost gets big fast!

And no way a 360 sucks over 1K CFM on it's own man. Check your math. 625 CFM @ 6K RPMs at best, assuming 100% V.E. Really with 88% V.E you're looking at ~550CFM.

josh19wrc

They're about 30K.

They make 350HP, but, they're 30K. The crazy assed people out on the east coast put 4 of them on the back of a 25 for boston whaler... That makes it a 250K dollar boat!

crx2211

I figured as much. Well maybe I'll just boost my 2 stroke Evinrude 85hp V4 ahahahaha! I really am looking to buy a newer/better outboard and will more than likely spend way more than I want, but 30k is absurd. I've been looking at some 2000 and newer outboards and can already tell Ima drop a lot of cash for a newer boat motor. Maybe I'll just keep the V4. It runs perfect and has never caused me an grief.