Kwak Turbo Bike build; questions

[ElSimplo]

Hi Guys!

New member here. Iam a car-guy, never did a turbo conversion on a bike. A lot different, especially the details.

Iam doing a Kwak ZX11 turbo conversion at the moment, but need some help. Turbo-hardware (exhaust manifold, MS2 wiring, oil lines and throttle body) are nearly done.

First, Iam using GSXR 1000 K3 TBs, direct fit, needs only some adjusting, with Siemens High Z Deka Pico Injectors 510cc.
Stock GSXR TBs use a non return fuel line, so I did a test on the bench with a 044 clone pump and tank attached. AEM Style FPR prior to the rail and a pressure gauge in the middle between rail and FPR. Fuel return line from the FPR back to the tank.
So, comes out I can adjust the fuel pressure, but without reference line attached to the FPR.
I can build a custom fuel rail, but there is simply no space between fuelrail and frame for fittings.

Read alot about this subject, but I am not enterly sure if will work. What do you think guys?

Second question.
Because TBs and MAP plus turbo or Alpha-N plus MAP isn´t as easy like MAP and a common plenum, I thought its much simpler converting the multi TB setup to a single throttle body in front of the plenum for easy tuning. 50mm or 55mm TB should be enough. I can pass on the last HP or TB response for easy tuning. I bet its the first bike converted to a single TB

Again, good or bad idea

Thank you,

- elsimplo

[R100RT]

If I understand you correctly,the manner you describe your fuel plumbing should work fine (similar to my project in fact), assuming adequate flow rate, and you have the patience to skew your VE table numbers seeing as how the FPR is not boost referenced (non return rails bleed through rapidly assuming you don't have a lot of aeration to contend with).
Seems speed density is easiest/ most popular option when forced induction is on the menu, map signals can be rather choppy depending on your engine characteristics. Not sure what you have there, 4 cylinder? That would certainly be far tamer than my opposed boxer twin - which I've dialed in a nice calm map feed with the following:
a) each inlet runner has an orificed feed off the throttle body (Honda CTX650 technology)
b) those tee into a miniature CO2 cartridge that has an orifice at its inlet end, drilled/ tapped for an outlet.
c) several ports off that outlet a) map sensor, b) boost gauge, c) W.I. Hobbs safety sensor, d) blow off valve signal, & e) FPR reference.
d) a tad of lag settings in the menu to ice the cake so to speak.
Good luck on project, photos required
Lorne

[ElSimplo]

Hi!

Cool, a BMW Boxer-turbo. I remember the old ads in bike-magazines from the late 70s / early 80s from Luftmeister et al. And at the same time, BMW prints funny anti-turbo ads two sides-on against turbocharging bikes (GPZ 750 Turbo, CX 650 Turbo etc.). I bet we see a turbocharged bike from BMW in the next time.

Yes, it´s an old Kawasaki ZX11 / ZZR1100C four-banger. Build is nothing special; Log-header, second hand turbocharger and parts from previous projects recycled

I think it´s better fabricating a custom fuel-rail with a return line instead of a returnless system? More work, but ok.
And I am doing the single throttle body conversion. TB from a Mazda Miata. Weird, but much easyr to tune. Or not

Thank you!

-elsimplo

[R100RT]

The LuftMiester (Master of Hot Air) systems, built by the RB racing guys were admittedly (by RB) challenged and hard on engines.
I am using "Non Return" twin fuel supply circuits to my inlet mounted injectors without any issues.
I don't know if you'll have issues or advantages by using a single throttle body. You want to evenly shair the airstream obviously.
I used 321 SS to fashion my turbo manifold (exhaust outlet to turbine inlet) as inter granular corrosion wrecks havoc on mild steel unless it's really thick fabrications.
Good luck, hope to see some detail as she finishes?
Lorne

[ArttuH]

I'm not sure if I understood correctly your fuel system question. Fuel rail type shouldn't affect if you can have return line to tank or manifold pressure reference to the regulator. Just connect the main fuel circuit "as usual", tank - pump -filter - regulator - return to tank. Then take supply to the fuel rail from between the filter and regulator. Only possible problem with this is that if air bubbles get in the fuel rail they won't get flushed out through the return. But in reality I haven't seen much problems due this. Using manifold pressure reference is highly recommended on boosted engines. Though if you are using just low boost you might be fine without it.

I would keep the individual throttle bodies. Usually that's easier to build and probably the throttle response will be better. Single throttle with plenum may cause weird throttle response at low rews if you don't get the plenum displacement and few other details right. Tuning with ITBs and turbo is quite easy too if you do it right. Basically you should tune it as Alpha-n with "multiply MAP" option on. That alone works completely fine in most of the cases. In addition you can add S-D as secondary fuel table and use it for fine tuning. Usually this is needed only if you are using variable boost pressure and even then required corrections are minimal.

[ElSimplo]

Hi!

Sorry for the delay, lost my password, because of an faulty HDD. And thanks for the replys. Yes I´m using the ITBs, not a single throttle body. Was just an funny idea

ZX11 runs now. Driven her 2x 5 miles , beside a small oil leak all good. Idle is at at 75kpa, all four vaccum ports connected together in to a small vacuum "reservoir", as RT100RT suggested, and then in to a small fuel filter. MAP signal looks good even without to much damping (80%).

To make things easier (for a not so experienced MS guy like me), I´m just use the stock trigger wheel (4-0) to get a tach signal (fuel only) for now to get a feel how these ITBs work. I have a 24-1 trigger wheel installed before my idea using the stock ignition system, worked good and fired right up. But using the stock ignition system makes things easyer for me until I understand how ITBs on a SD install work without the need to get the ignition right at the same time. No wastegate-spring in the wastegate, it should be save to drive around to get some datalogs.

So, problem is now, the stock-triggerwheel triggers 4 times per engine cycle. No surprise, it doubles the real rpm. Using 8 cylinder setting works, but I have trouble understanding the interact of "how many squirts - sim/alt - and numbers of injectors on a "cheated rpm" install. I know the req_fuel is wrong. Sure it works, but not right.

TS is set to req_fuel 9ms, AFR 9.8, 1109cc, 230cc injectors (4x), 2 squirts, alternating, 8 cylinders and 8 injectors. This cheated 8 cylinder setting confuses me a lot.
Injectors are wired in firing order.
I know, stock GSXR 1000 K3 injectors are much to small for a E85 turbo application, but they make things easier again for testing.

Can someone please help me out with the right TS setting? I think my current setting is just like a continous style injection, it idles at pw 3.7ms at 14 AFR.

Thanks!

[ElSimplo]

little update:

switched back to my 24-1 wheel and big pair of injectors. All good now, pretty good idle, done in an hour. Looks like there is no other easy way except running the right trigger wheel and injectors from the start. Its harder but I think its worth in the end not changing two or three things at the same time. And one suzuki-injector was bad.

I try AN for the primary fuel-load and SD for the secondary; looks complicated

Bye!

[ArttuH]

I try AN for the primary fuel-load and SD for the secondary; looks complicated

It may look complicated at first but actually it's quite simple in the end. It's maybe easiest if you think it as pure AN where you have SD as backup for cases where you need extra compensation. Or actually you can start tuning as pure AN and forget the SD completely until you find need for it (maybe never happen).