Arttu

Rule of a thumb is to make combined cross section of the holes the same as plenum feed pipe. Radius won't hurt I guess but on the other hand probably won't make big difference either. In the end the idea is to create restriction to direct air flow. So better the holes flow less effect they have. To some degree. Of course it would be better if you can change air flow direction smoothly without creating too much back pressure but usually this requires more room. It's balancing as usual.

Installation was really straightforward. I used tach signal from Dyna as trigger for the Megasquirt. Worked fine without any hiccups. The setup was working just fine in general as well. Although this was my friend's bike so I can't tell much how it performs in everyday use. But at least he has been happy and I didn't notice anything strange during dyno tuning. Obvious drawback with this arrangement is that ignition mapping will be limited to what the Dyna can offer. On positive side installation and tuning is somewhat simpler since you don't need to care about triggering and ignition settings. Especially if there isn't ready trigger solution available for your engine and ECU.

I have done one installation that way. Megasquirt ECU.

Yep, like you probably have noticed published info about those IHI turbos is quite limited. But based on what I found they are probably somewhat smaller than your current turbo. And VF24 and VF29 should be a bit faster spooling than VF23. So if those are easily available they are probably quite good choice. Garrett one is most likely again slightly smaller and faster spooling than any of those IHIs. And you can get them as new for relatively reasonable money

Those IHIs look quite ok based on info that is floating around the net. Although difference in spooling compared to your current one might be quite small in the end. One alternative with ball bearings could be Garrett GT2560R. It's about the same size than those IHIs or maybe slightly smaller.

Sounds like the turbo wheel slowing down.

Did you measure AFR on dyno? If yes, how it was looking? Any way, if it's stopping at 8000rpm regardless of gear and load then it sounds like electrical problem. Or then fueling goes really badly wrong at that point but that sounds unlikely as you have tried two sets of carbs.

Yes. Less optimal trigger wheel pattern may cause trouble on starting. The ECU may have difficulties to read crank position correctly because crank speed varies a lot during one revolution. Typically more teeth means more reliable reading, up to some limit.

Around 300rpm. It can vary quite a lot depending on battery, starter condition, compression and so on.

Once helped a guy to install and setup one on a car. It was looking quite ok to me, all needed features were there and it was relatively logical to use. But that's all what I can say, I don't have any real experience about it. However, I know a couple of guys using those on boosted bikes so most likely it would be fine for you too.

Microsquirt should be perfectly fine for basic engine management. Meaning it can control spark and fuel injection accurately enough for boosted bike engine. On top of that it can do some additional tricks too like boost control, quick shifter and so on. But it has somewhat limited IO capabilities so if you want plenty of this extra stuff you may face limitations pretty quickly. If you want MS3 then I would recommend that MS3 Pro unit. DIY versions of Megasquirts (v2.2, v3.0, v3.57 main boards) aren't good for bike use IMO. They have lousy connectors, they are bulky and not water tight. In addition of Microsquirt and MS3 Pro there are some quite good unofficial versions for both MS2 and MS3 but might be better to not list them here.

Pump speed doesn't affect to mapping at all since the pressure regulator keeps pressure constant. Naturally that requires switching to full speed before the engine demand exceeds pump flow at low speed. Sure it's one more thing to go wrong. But the reality with air cooled GSX engine is that you will need some special tricks if you want an EFI pump that is capable for high power figures. The generator simply can't keep up with the pump and other consumers.

Quick answer is yes. How depends on Megasquirt version. In most of the cases you will need a separate coil driver module between the ECU and coils. Something like this: http://www.autospark.eu/shop/injection/ignition-modules/bm325-transpo-ignition-module-bosch/

Walbro pumps are relatively small compared their output. They are also reasonably priced and quite easily available. Current draw is on typical level relative on the output, maybe somewhat better than with some other pumps. For example this might be quite ok for you application: http://walbrofuelpumps.com/walbro-gsl393-fuel-pump.html Of course it's still way too powerful for your engine but not too badly. Current draw seems to be around 5A at 3bar which might be ok for Katana generator depending on how much other consumption you have. PWM control works to some degree. Usually these roller cell type pumps can be slowed down to around 50%. When you go below certain level the pump kind of locks up and stops pumping. I have done a simple circuit for this purpose. On my turbo GSX the pump runs normally at low speed and switches to full speed by control signal from the ECU. I have also another one on normally aspirated SV650. There it runs continuosly at half speed. I think I still have some PCBs and other components for this circuit and I can make more of them if there is need. Cost would be something like 30-40€.

Well, that's doable, at least in theory. But not worth of required effort in reality, trust me. Get some universal aftermarket ECU.

Tricky thing with these IHI turbos is that there isn't much specifications available for them, like compressor maps etc. In addition model numbering doesn't seem to follow any logic. However, there are some listings about different models around the web with brief descriptions and estimated flow capabilities. If I recall correctly VF22 was the biggest one, like said. VF34 is just slightly smaller but later design and supposedly quicker to spool. VF36 was very similar to VF34 but with dual entry turbine housing and again slightly smaller. The rest I can't remember. It's also worth of noting that some VF models are with plain bearings.

All right then, some candidates that should fit to those requirements: Mitsubishi TD04-13, TD04-16, TD05-16. Max. power roughly 230-300+ hp. KKK / Borg Warner K04. 210-300hp depending on version. Be careful if buying used one, plenty of cracked exhaust housings. Garrett GT2560R, GT2860R. 270-350hp. Aftermarket ball bearing turbos. Nice option if budget allows. Holset HE221, HX27. About 300hp. Reasonably priced as new. Maybe not the most optimal for your case as they are optimized for quite high boost (I think). Then IHI makes some nice ball bearing turbos as well. I have a VF34 on my 1230cc GSX and I like it a lot but it might be slightly on large side for your plans (350+ hp). There are smaller versions too but I can't recall models right now. 200hp should be easy for 1200 Bandit. I think it should handle up to 300hp without major updates to the engine.

Turbo is good, no turbo bad Seriously, choice depends heavily on your preferences. How much power you want, what is planned use, how much you are willing to spend etc. There are plenty of options for good results. As far I know there is plenty of quality variation on Chinese (unbranded) turbos. Best of them are as good as anything else, worst might might be just lump of metal barely resembling a turbo. If you get one from some reputable distributor it will probably work just fine. Lowest price *bay find might be different story. I don't have much personal experience about them but I know that plenty of people are using them with good results and I haven't heard too many horror stories recently.

Hmm, no, 8 A123 cells, 4S2P, total 4.6Ah or something like that. I have that kind pack on wife's SV650. I tested it on my GSX when the Hobbyking pack started to give up. I would say that A123 pack cranked the GSX engine as well as larger Hobbyking pack when it was new. Now I have about 8-9Ah of Chinese A123 copies on GSX, has been working fine by this far. Recently I tried cranking it when bike has been a night out at -10C. It needed some persuading but eventually it fired off

I have had slightly bad experiences with those Zippy packs. I have done few race batteries (total loss system) with those and one pack for my road GSX as well. At first about every fourth pack from Hobby King has been defective in the beginning. "Buffed" packs or bad imbalance between the cells. For my GSX I made a 8.4Ah battery, two of those packs in parallel. It cranked the engine pretty well but not as well as you would imagine based on specs. Current output also dropped steeply in low temperatures. Overall I would say that an A123 cell pack with half capacity performed at least equally. Life time of the packs has also been quite short. Typically they "buffed" and lost capacity after an year or two. I haven't been using those during last couple years so possibly their quality has been improved since that. But I doubt it. On the other hand Chinese A123 copy cells have been surprisingly good, nothing to complain about them. But apparently shipping them from China has got more complicated recently.

GSX-R600 06-07 seem to fit quite nicely on oil cooled engines with later model Bandit intake boots. I'm installing a set at the moment. I also have a hunch that secondary injectors on those might be quite big so they could be capable for some real power with stock injectors. I'll try to find time to measure them on next few weeks. I will keep you updated.

For rough estimations the blower displacement / rev and maximum rpm are enough. Like you already figured out the maximum rpms of the blower and engine determine maximum drive ratio that you can use. 10 000 rpm for engine and 16 000 for the blower will result maximum 1.6 ratio like you calculated. For boost pressure estimation you need engine displacement, blower displacement and drive ratio. The formula is: blower displacement * drive ratio / engine displacement (per rev). So if you take that 500cc Aisin, drive it at 1.6 ratio on 1000cc four stroke engine it will look like this: 500cc * 1.6 / (1000cc / 2) = 1.6 pressure ratio = 0.6 bar = 9 psi. Engine displacement is divided by 2 because a four stroke engine has intake cycle on every second revolution. In real life the result can be somewhat different due to various factors like engine volumetric efficiency, valve overlap, air heating and so on. But if you just want to figure out if the blower will suit to engine and what drive ratio to use this should be close enough.

Here is something that I made few years back. Inside: And finished part. I don't know how efficient it really is but based on EGT readings flow balance between the cylinders is pretty good. And engine produces quite healthy power figures compared to boost and tune of the base engine so the plenum can't restrict flow too badly either. In my opinion the most important target for plenum design is to ensure even air distribution between the cylinders. This can be tricky if air is entering from side. Velocity of incoming air tends to pack air in opposite end of the chamber and then cylinders on that side will get more air. To prevent this some kind diverter arrangement is needed. Typically this is done with dual chamber construction like on my plenum and those in second post. Idea is to kill air velocity in the first chamber and then bleed air to the main chamber through narrow slot, row of holes or something similar.

Most likely it will work fine. Although you may notice some hiccups when fuel level is low. How low you can go without problems will depend on tank shape and union placement. On my GSX I have both take-off and return in place of the original petcock and it starts to suck air every now and then when there are a couple of liters fuel left in the tank.

They started weld cranks on late 82'. So all black engines should have welded cranks and silver ones non-welded.