Future turbo considerations looking at GenI and GenII bikes

Caithness

Registered
Hello,

I've been watching the classifieds and checking out bikes for the last few weeks, and I'm going to look at two bikes this weekend, a well-kept 2007 and a low-mileage 2008. From everything I've read on the matter, the GenII is a better bike stock for stock in terms of suspension, braking, power, engine management/economy, comfort and refinement. In my opinion the GenI wins out on looks, but that's a matter of intense debate and opinion :D.

I intend to enjoy this bike in mostly stock form as a high-speed sport touring rig for the first few years, but part of what draws me to the Hayabusa is the potential for crazy turbo power down the road. In the past I built and tuned an 11 second AWD Eclipse and I've always wanted to build another turbo vehicle.

I've been comparing the pros and cons of GenI vs GenII and so far this is what I've got as far as turbocharging is concerned. Please let me know if I'm on the right track.

The GenI seems like it is better suited to a lower budget DIY install. RCC or other stage one non-intercooled kit with a 6psi spring, 1:1 regulator, s2000 injectors and an ECU editor setup. Much more manageable on a stock wheelbase which appeals to me, probably 5-6K all said.

From what I've read the GenII really needs the engine gone through to coexist happily with a turbo setup. Stiffer springs and stainless valves, forged pistons and might as well do the rods at this point. Now, you can do a stage one non-intercooled setup, but having already gone through the trouble and expense of building the engine you might as well drop the extra coin for the ultra plenum and upgraded injectors. At this point you're pushing so much power that you're going to want to stretch it, and between building the engine and tuning this beast you're really going to want to have a reputable shop do the work. Now we're talking over 10k in parts plus labor which is a considerable sum.

I'm trying not to worry too much about what might happen in the future and focus on finding the overall best bike for me now, but any input to sway me one way or the other would be welcome. Regardless, hope to join the Busa ranks soon and greetings to everyone!

-Jordan
 
You're gonna want to talk to Frank at Powerhouse or Rob at Boosted. If budget is a concern I would go with the gen I. If budget isnt a concern then I would do the Gen II. More power in stock form and the look will grow on you once you start customizing it.
 
i would do gen 2 as best option ,
sure you need to replace valves if your planning on higher boost , but gen 1 valves and springs are a good option in the gen 2 for a budget build ,
You get a better engine management package as the upside , flashing a gen 2 for boost gets you pressure referenced fuel adjustments, ign retard, boost control as well as other options in the program, all in the std ecu

If you do a budget gen 1 your better off with the fmu and std injectors than 1:1 and s2000, editor on gen one has only tps mapping ,
and for both with a low boost setup i would still decompress .040 -.080 , head stud , ceramic coat pistons
 
So the GenII ECU can do boost-referenced tuning but the GenI setup doesn't? That's good to know. I didn't know what to make of it when I first saw the TPS-based tuning. My DSM used a MAF setup and I worked on my buddy's car with a MAP conversion. I get why the stock setup uses the TPS tuning with the ITBs, but no load value at all other than a TPS-based approximation, I didn't see how that would work with boost. Maybe OK on WOT pulls and not as great at less than full boost.

If it's best to take the head off to put in a spacer with a GenI anyway, swapping the valves/getting a valve job on the GenII isn't that big a deal. Other than the higher compression, is there a big difference in the composition or design of the GenII piston that makes it weaker? Is the top ring closer to the top of the piston or did they use a weaker alloy or something? All I've been able to find is the GenII rods are heavier/longer and the GenII piston is lighter because of the smaller wrist pin.

Looking through old threads I got the impression that the spacer was a kludge fix and people seemed to give the GenI a higher safety margin for power/torque on the stock internals. If the GenII with a spacer and conservative tune is happy in the 4-6lb boost range and the same 230-250hp range as the GenI then it's more apples-to-apples instead of apples-oranges like I thought.
 
Boost fueling through the ecu on a Gen II will only take you up to 30 pounds of boost. Since you have no intention of making over 500 rear wheel, that would not be a concern. RCC has a very nice Ecu Editor Stage One kit that can easily make 350 rwhp on the stock injectors with upgraded internals on race fuel. Gen 2 stock compression is too high - as a bolt on, you can only safely make 4 pounds of boost, 220, maybe 230 rear wheel. Hardly worth it. If you are going to pull the head to change out the valves and springs, you might as well do some drop-in Wossner turbo pistons - these enable you to use a stock base gasket, no spacer. The advantage? You can drop the stock cams right back in with no adjustable cam sprockets or degreeing. Gen 1s have their advantages as well, especially if you plan on building a monster hp bike.
POWERHOUSE will continue (for a time) to offer $200 off on any RCC turbo kit, org members only!:laugh:
 
Frank is right, unless you want some crazy HP a gen 2 is a better set up, mainly for the electronics, and drop in pistons with no spacer is cool too.
 
GenII it is! Picked up the Black/Red 2008 I was looking at. Only been on a few rides but it's a heck of a bike, much smoother and less brutal than I thought it would be. Turbo seems a bit silly after seeing just how fast the stocker will go with so little effort, but that doesn't do much to change the appeal. We'll see what happens over the next few years. In the mean time I'm enjoying the benefits of the redesign and have come to the sudden realization that the GenII was the better-looking bike all along. :laugh:

The more I read about it, the more the tuning advantages of the GenII Ecu seemed like a bigger deal than the increased potential of the stock block first gen. There just aren't any other really appealing tuning options. Piggyback systems lack in functionality and control, the popular standalones are expensive overkill for a street setup and have a significant learning curve. Proper tuning is priority number one for a reliable forced induction engine so the ECU flash options were a big plus to the GenII.
 
GenII it is! Picked up the Black/Red 2008 I was looking at. Only been on a few rides but it's a heck of a bike, much smoother and less brutal than I thought it would be. Turbo seems a bit silly after seeing just how fast the stocker will go with so little effort, but that doesn't do much to change the appeal. We'll see what happens over the next few years. In the mean time I'm enjoying the benefits of the redesign and have come to the sudden realization that the GenII was the better-looking bike all along. :laugh: The more I read about it, the more the tuning advantages of the GenII Ecu seemed like a bigger deal than the increased potential of the stock block first gen. There just aren't any other really appealing tuning options. Piggyback systems lack in functionality and control, the popular standalones are expensive overkill for a street setup and have a significant learning curve. Proper tuning is priority number one for a reliable forced induction engine so the ECU flash options were a big plus to the GenII.
Don't knock the benefits of an ecu flash paired with a PCV tune. Js
 
The more I read about it, the more the tuning advantages of the GenII Ecu seemed like a bigger deal than the increased potential of the stock block first gen. There just aren't any other really appealing tuning options. Piggyback systems lack in functionality and control, the popular standalones are expensive overkill for a street setup and have a significant learning curve. Proper tuning is priority number one for a reliable forced induction engine so the ECU flash options were a big plus to the GenII.

Congratulations on your new bike. IMO you are mis-understanding the "functionality" of the Gen 2's ecu boost fueling capability and it's relationship with off-boost ecu tuning. Yes, proper tuning is priority one, and there are many tuners out there that can attain this goal in a variety of ways. I have over 15 years of dyno tuning experience on a variety of hardware and different platforms. Piggyback systems do NOT lack functionality and control and IMHO, many of them have huge advantages compared to ecu tuning when it comes to fueling. For a turbo bike, ecu boost fueling on a Gen 2 is convenient, yet has its own limitations. I would probably not recommend this route for anyone looking for more than 400 rear wheel, even though it is easily attainable this way. As a tuner, I feel that ecu tuning is sticks and stones compared to other options out there. The important thing is that you get with a tuner you trust - someone who has had and tuned on a dyno for at least two years - and ask them what they prefer, what they have seen the best results with. And go with that. Above all, remember that the best results aren't necessarily the highest number, but more about throttle response, drive-ability and a good mannered bike that is a pleasure to ride. We have put several ROADRACERS on turbo bikes successfully, guys that never believed a turbo could behave predictably on a road course. Yes, proper tuning is number one!:laugh:
 
I looked into the PCV and you guys are right, it's a powerful device for under $400. I was stuck in my ways thinking about crude tuning boxes like the Apexi SAFC which just messed around with your maf/map signal to push the ECU up and down the fuel map. The last time I actually looked at the PC units was with the old PCIII and I saw "low/medium/high rpm" adjustments and instantly tossed it in the same mental pile without looking at what it could do.

The PCV directly modifies the injector pulsewidth, right? The full 3D fuel mapping they're talking about is rpm/ tps / map sensor? That sounds more robust than what I've seen in the free ecu flashing software and I don't think the paid software even has boost fueling.

I'm guessing a big benefit is it is much easier and faster to dial in the fuel curve with the PC unit than having to reburn a chip. PCV for fuel and one of the ecu tuning boxes for timing/rev limit/speed limiter and logging- unless you guys have a preferred datalogging solution. For track use only of course; street tuning a turbo Busa is probably asking for trouble. :laugh: And with the money in the rest of the setup paying a real pro to tune in the bike only makes sense. When it comes to tuning I'm more of an enthusiastic amateur- I've got a lot of respect for the skills veteran tuners bring to the table.

Anyway, only matters now if I decide to get my tuning setup going early to dial in the bike for the full exhaust and filter and get familiar with it. The toy fund needs some serious replenishing and I see myself adding a dual sport to the stable to go where the Busa can't before going too crazy with it.
 
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