i was thinking that a restrictor will cause the inlet air temp to go up .
My supercharged K8 project...
The bike pictured above is my bone stock K8. A friend gave me a fantastic deal on this bike last year, and it has just under 2000 miles on the clock. I love this bike for the same reasons everyone does -- incredibly smooth, extremely capable and controllable, great power, and fantastic ergonomics for a supersport machine. The local Dynojet 250i says it puts down 152whp (SAE corrected), which is actually more power than a full-exhaust, PCIII-tuned '04 ZX-10R produced on the same dyno.
Now, normally the next step would be to add an exhaust, change the gearing around, or add some braided lines, and while I'll eventually get to those mods, I have something different in mind right now...
It's a Rotrex C15-60 supercharger, right off the plane from Denmark. This little unit can support over 230whp, and that's the number I'll be shooting for with my little project here. Also, the impeller wheel used to be cast, but these new wheels are apparently machined out of billet.
Before you ask, yes, I am a power junkie. There's just no going back once you've ridden a boosted literbike...
You can see how small it actually is compared to the bike. Somehow, some way, it will fit in there...
After staring at this sight for a couple of days, I realized the only place to put this thing is in-between the engine and the radiator, just below the frame. I'd love to stick it up higher, but the frame would get in the way of the belt (which is a dealbreaker) and the radiator fan would also have to be relocated. Placing it lower eliminates these problems, but makes it much harder to hide the drive behind the fairings and also places the inlet of the Rotrex very close to the header. I also do not want cornering clearance to be compromised at all, so it will be in as far (and up as high) as possible.
If anyone is wondering how I plan on driving this thing, take a look at the picture above. The M10 bolt currently fastened into the end of the crank will be removed and a machined adapter will take its place (this adapter has to locate perfectly off the crankshaft for this to work). A pulley will sit on top of this adapter and then drive the supercharger via an 8mm synchronous belt. The supercharger bracket will either take the place of the stock cast cover or locate off of it -- I'm not exactly sure yet which way to go.
There's a lot of work left to be done, but I'm looking forward to it. I plan on tuning the ECU directly and, of course, it will run on pump gas. In the meantime, wish me luck, and stay tuned...
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I hope you guys are ready for pictures, because I have a lot of them coming up right now...
I sent the brand new OEM pistons out to SwainTech for coating. They ceramic coated the tops and put an anti-friction coating on the skirts. Since the old pistons scuffed in the bore, I figure reducing the heat they see and making sure the skirts don't stick in the case of a lubrication breakdown is a good thing. I also kept the compression ratio stock.
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I was able to swap the pistons without removing the crank, but every other part of the engine had to be disassembled. I bought a torque angle gauge to tighten the fasteners to factory spec.
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The engine finally all bolted up. I figured that as long as I had it out of the bike, I might as well wrap the tops of the header tubes to reduce the heat even more. Also, that engine you see in the background is going to be a killer -- 375ci small block Chevy, SB2.2 heads (NASCAR stuff), dry sump, all roller drivetrain, all forged internals, 9000+ rpm redline, supercharged and fuel injected. Should be a fun little street car if I ever get it done.
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Engine getting bolted back into the bike. This was a 2 person job.
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Another shot of the airbox...
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Ready for her maiden trip around the parking lot. This thing was a smoke machine on startup. Smoke was everywhere; out the pipe, under the tank, it looked the bike was on fire.
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I sent the brand new OEM pistons out to SwainTech for coating. They ceramic coated the tops and put an anti-friction coating on the skirts. Since the old pistons scuffed in the bore, I figure reducing the heat they see and making sure the skirts don't stick in the case of a lubrication breakdown is a good thing. I also kept the compression ratio stock.
I was able to swap the pistons without removing the crank, but every other part of the engine had to be disassembled. I bought a torque angle gauge to tighten the fasteners to factory spec.
The engine finally all bolted up. I figured that as long as I had it out of the bike, I might as well wrap the tops of the header tubes to reduce the heat even more. Also, that engine you see in the background is going to be a killer -- 375ci small block Chevy, SB2.2 heads (NASCAR stuff), dry sump, all roller drivetrain, all forged internals, 9000+ rpm redline, supercharged and fuel injected. Should be a fun little street car if I ever get it done.
Engine getting bolted back into the bike. This was a 2 person job.
Another shot of the airbox...
Ready for her maiden trip around the parking lot. This thing was a smoke machine on startup. Smoke was everywhere; out the pipe, under the tank, it looked the bike was on fire.
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I let it warm up, then took it out for the first spin. I altered the engine rpms the whole time and made sure to keep the new rings loaded. Within a mile or two the smoke was gone. 20 miles later I brought it back to the shop and changed the oil.
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I did a bunch of custom, cost-effective mods while I had it apart. I found another swingarm on ebay, stripped it, polished it, brushed it just right, then cleared with some epoxy paint. I threw on a 520 sprocket set (stock ratio), RK chain, Galfer wave rotor, HEL brake lines, and swapped the wheels to freshly powdercoated RC51 5 spokers.
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It was not easy making the wheels work, and the swap required new bearings, seals, spacers, and some machining to the wheels themselves. The front calipers are R1 units with custom spacers, grabbing 1000RR rotors. I love those calipers, and just might have to swap the master cylinder for the stock Brembo unit (I have that setup on my VFR and the feel is better than this current setup).
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The exhaust sounds awesome on the open road. Really deep while cruising, aggressive while revving up, and the smoothest, sweetest, most insane sound near redline. Can't even describe it.
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I did a bunch of custom, cost-effective mods while I had it apart. I found another swingarm on ebay, stripped it, polished it, brushed it just right, then cleared with some epoxy paint. I threw on a 520 sprocket set (stock ratio), RK chain, Galfer wave rotor, HEL brake lines, and swapped the wheels to freshly powdercoated RC51 5 spokers.
It was not easy making the wheels work, and the swap required new bearings, seals, spacers, and some machining to the wheels themselves. The front calipers are R1 units with custom spacers, grabbing 1000RR rotors. I love those calipers, and just might have to swap the master cylinder for the stock Brembo unit (I have that setup on my VFR and the feel is better than this current setup).
The exhaust sounds awesome on the open road. Really deep while cruising, aggressive while revving up, and the smoothest, sweetest, most insane sound near redline. Can't even describe it.
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More...
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I still have to get the fairings done (I'm modifying them, too), but promise to post pics once they're back on the bike.
I still have to get the fairings done (I'm modifying them, too), but promise to post pics once they're back on the bike.
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