V8 Project More is More


V8 licenseplate It's been a year since report #7; about time to move on to #8. Yes, my bike is street legal but I still don't allow it to get on the road. It has proven itself to be rideable but what I want is performance, letting out what's potential inside. And that's certainly more than 357 bhp at the rear wheel we measured in April 2012.
V8 Engine One moment you have a rideable bike, the next moment just a tiny engine.
gasket This is how the inside looked on October 30 2013, as I assembled the intake. The grey edges I'd filled with 2K filler: hard as aluminum, water resistant, oil resistant, fuel resistant, heat resistant, just perfect. Well, nót perfect. Appearantly this stuff is not glycol resistant, and that is a main component of my cooling fluid. Bad luck.
TIG welds While I was at it, I made some stainless steel spacers and washers for the manifold.
Water methanol schema On a turbo bike intake air cooling is eminent for engine performance (see report #6). So I continued optimizing the water-methanol injection system. I added two pressure switches for a two-stage injection system: the first one (SQ1) activates the first spray at 0.25 bar, the second one (SQ2) adds the second spray at 0.75 bar turbo pressure.
Holl Like so many times before I visitedTechnisch Bureau Holl. And like all the times before they patiently helped me find the connecting components.
Cardboard box From simulation to cardboard.
Fogger Important part: the nozzles. They vaporize the mixture so the intake heat is cooled down to the max.
Diving air bottle To pressurize the air bottle to 20 bar I tried several 12V electric pumps: their specs were promising but none of them met the expectation. One of them even caught fire. Crap. I'm building a static pressure system on my bike so why not a static refill station? For half the money of a pump I bought a 200 bar diving bottle. Just perfect.
pressure testing the swing arm When a pressurized, toxic, blinding and invisible burning mixture like water-methanol is involved, you want to take as little risk as possible. So I did an under water pressure test.
Peter Scheepers No wonder he looks content.
Wide band sensor On May 17 2015 we had another dyno day. There were familiar problems with lambda sensor and the PWM valve (see multiple reports), and after they were solved we did a run.
Dyno chart The engine accelerated like hell: it took no more than 1.5 seconds to reach 6,000 rpm. And the graph looked smooth and promising too. At first. Looking closer: only 156.5 bhp at the rear wheel. My GSX-R has that! Disappointing, and puzzling.
clutch temperature I hoped for wheelspin but that was not the case: it was the clutch that slipped, confirmed by the fast temperature rise during acceleration.
Dragrace clutch That is a common fact when tuning a bike, or a vehicle in general: the moment you improve the engine (and thus performance) the next weakest spot comes to light. In this case the clutch: it couldn't keep up with the acceleration.
Software tuning That didn't mean it was a lost day. Peter optimized the software ...
Hardware tuning ... and Niels the hardware.
Checking parameters So progress was made. The engine did not overheat a single time ...
reading datalogs ... and nothing was destroyed. Always a good thing to celebrate after a test day. Next steps to take: temporary pause working on the water-methanol injection and focus on 'getting grip'. Goals: being able to measure the clutch slip and, after that, find a remedy.
Dyno checking On October 5 2015 Peter and I had another dyno day. A facemask was more essential then ever before: you don't want to inhale exhaust gas nor burned water-methanol as it might turn in to formaldehyde gas. Sadly the slip sensor did not live up to its hopes and expectations: for whatever reason the results were corrupt and thus useless. Damn.
second dyno chart We decided to enlarge the centrifugal weights on the clutch. A week before the test I'd spent a full day to egalize the clearance of the clutch to 0.7 mm: getting it exactly right is crucial for grip. Both changes resulted in good grip: one test gave us 341.8 bhp and 491.2 Nm torque at the rear wheel. Not bad but not good as well: these are not the numbers I'm aiming for.
purge switches We're still not sure why the bike doesn't break the 350 bhp barrier with ease: it has the potential of doubling it, and more. Intake heat is still an issue: I just finished building a purge system for the water-methanol injection system.
wiring purge switches That way all hoses are filled with fluid the moment we test on the dyno, ánd I can activate the system any moment I want to, to see and manipulate its influence on the intake temperature.I tested the system with air. The lower switch activates left and right spray individually. The top switch activates both nozzles simultaneously. Click the play-button to see the result. Works just fine. I'm curious what it will bring on the dyno.
EUREKA! So, what's next? Continue testing and tuning, that's what's next. I made a (ever growing) to-do list for the next dyno day with Peter and Niels. Parallel to that I recently contacted some experts on the combination 'V8 + turbo' to discuss the possible bottlenecks in the system. Am I looking forward to that? Yes, of course. Discuss, plan, develop, mill, lathe, weld and test: that's what R&D a.k.a one-off bike building is all about.
  So, again: to be continued...