Turbo bike part 1 - Brain transplant

[Maj750t]

Got to be easier than silicone hose & hoseclamps ,
<i></i>

[gazza414]

At those pressures its a law of diminishing returns wrt actual flow achieved thru injector. You may have even reached choked flow conditions? have you flowed the injectors at various pressures? and also see how they have responded when sent a signal? <i></i>

[Blackkat]

Funny you should mention 15# as that seem to be the magic number that the throttle bodies would hold before strapping, on my bike ( have a long phillips head screwdriver handy).

Leonard.

<i></i>

[Geribusa]

Quote:At those pressures its a law of diminishing returns wrt actual flow achieved thru injector. You may have even reached choked flow conditions? have you flowed the injectors at various pressures? and also see how they have responded when sent a signal?

I'm not familiar with the term "choked flow conditions". Please can you explain what you mean with this.

As far as flowing my injectors I haven't had them flowed. I figured that since people had been scraping 300hp with stock 'busa injectors, I would be safe enough running 300hp from the larger capacity blackbird injectors I have fitted. So far it seems to have worked well. <i></i>

[gazza414]

Geri, the term choked flow originates from fluid dynamics both on compressible and non compressible flow wrt nozzles. Basically its a term which decribes a condition where no matter how much additional pressure you add to the supply side of the nozzle or orifice then no additional output flow will result.
For example I flowed a set of injectors recently which will give you an indication of what I have mentioned

@ 3bar supply flowed 438cc/min
@ 4bar supply flowed 492cc/min
@ 5bar supply flowed 510cc/min

the increase in flow from 3 to 4 bar has resulted in a net increase of 54cc/min whilst an increase from 4 ( ~60psi ) to 5 ( ~75psi ) bar has resulted in an increase of flow of only 18cc. I did not check 6 bar ( 90psi ) but you can extrapolate the result I'm sure.

Also when you look at pump manufacturers specs you'll notice that although some pumps can supply 6bar they draw alot of current and the flow rate is reduced alot... some to the extent that they just dribble or in some cases actually stall.

If my memeory is correct the Blackbird injectors are rated at approx 330cc/min @ 3bar . What I'm not sure about if that is indeed fully open or at say 75 to 80% duty cycle?

hope this helps a little

ps. as the pressure is also increased the spray pattern changes and so does the droplet size. <i>Edited by: Gazza414 at: 18/10/05 4:05 pm
</i>

[Geribusa]

Some really great info there, I appreciate you taking the time. Fuel injectors are not something I know a great deal about.
Seems like a "law of diminishing returns". I guess this is why, with a bike fuelled as mine is by a boost-referenced FMU, and the A/F set correct for max RPM they tend to go rich in the mid-range unless a powercommander is used to map it out. I guess if the mid-range were to be set correct then the top-end would go lean because of the way the increase in flow drops off faster as pressure increases. The rising-rate FMU really is the poor relation of turbo fuelling systems, and pretty much the crudest I would say. <i></i>

[Maj750t]

The FMU has its limitations but it is a simple way to get a desired result, you get to keep your std injectors & ecu and the components the ecu runs.Doesn't cost a whole lot of

A boost based piggyback would be better but then there is the cost of injectors and you have to remap from idle.

I'm using a Fmu on my streetbike and planning a change to a boost based piggyback and a straight rate regulator, not that its necessary i just have a compulsion to fiddle with things. <i></i>

[1hotBUSA]

Hi there,

In putting mine together I seriously considered the FMU and stock injectors. However with the opportunity to run the TSI unit came along I thought that it would be the ultimate way to go on my bike.

And I like to fiddle too Gary, although the priority is just getting the thing up and running boosted on the road at this point in time.

Regards
Graham
1hotBUSA
2000 Suzuki Hayabusa Red/Grey Bog standard except for bling and a kanooter valve. Oh and a turbo kit on the floor.
Strike a blow for freedom...Smash a speed camera!!!
Red Bikes Rule!!!!!<i></i>

[Geribusa]

Oops yes I'm sorry about taking over your thread. I've been reading it from the start with great interest, but I've realised I don't know what your actual kit consists of. Apart from the fuelling, what hardware are you using. Your sig line says a "turbo kit on the floor" but what is it?

Geri <i></i>

[Maj750t]

Its more along the lines of yours, mine, and a select few <i></i>

[1hotBUSA]

Hi Geri.

My setup is going to be as follows;

Garrett T28 Turbo running at max 10psi boost. The system is going to run water injection rather than an intercooler partly because of price, and partly because I like to tinker with electrical things, and an intercooler is just plumbing.

For fuel I am going with a 1:1 boost referenced regulator and an aftermarket ECU. I am using a TSI unit, dunno if you have them in the UK, but they would be similar to a poor mans Motec unit. I will be changing the stock injectors for something bigger which will allow me to avoid using a 2:1 FMU. This I have read is the ultimate in control for this application.

A lot of the parts, information, and inspiration has come from you guys so hijack away. We are still on the same topic, and the "more power" threads have been getting a lot of attention so i would say there is interest out there.

The kit goes in December after Jindy and Snowy Ride are behind me. Hope to be back on the road, boosted by Feb. Things left on the list to get include injectors, and the water injection system. After that the fitting begins.

Regards
Graham
1hotBUSA
2000 Suzuki Hayabusa Red/Grey Bog standard except for bling and a kanooter valve. Oh and a turbo kit on the floor.
Strike a blow for freedom...Smash a speed camera!!!
Red Bikes Rule!!!!!<i></i>

[Xhiler8r]

Graham I have just sat here and read this whole fucken thread and damn man I feel like an expecting father again I cant imagine what you are feeling WTG bloke keep at it and hope all works out for you Regards Bill

"Secret Mod Group Is Kicking Butt"

Busa's Rule On The Rest<i></i>

[Geribusa]

Sounds like you're in the final stages there. I wonder if you had times, like me, when you were stuck in the doldrums wondering if you were ever going to see an end to this job The first time you wind on the power makes it all worthwhile mind you!

Dunno if you've seen it Graham but here's my web page detailing some of the build process:

peterrimmer.myby.co.uk/petesturbo.htm <i></i>

[fasterfaster1]

It's a credit to you .................Geri both the ingenuity/workmanship and dedication to see the project thru. As you well know ain't it addictive but, once that throttles turned ?
FF1 <i></i>

[1hotBUSA]

Hi Geri,

Yes I have indeed visited your site and downloaded a lot of the pictures off it. I have hundreds of pictures of turbo installations on my computer so that I can look at what people have done and how I want to approach the project myself.

Prior to installing I need to get the injectors, the water kit, and then it's just a case of hoses and fittings, and fabricating what I need to do. I am going to be retaining the stock twin exhaust system, but joining into it at the single pipe path. Have thought about building a full system, but should be able to get away with joining the two systems that I currently have sitting under the house.

It still feels like a way to go, but I've had the bike off the road for other things at the moment. The turbo install will take place in December after the convention. or when I have everything here, whichever is the latter.

Good talking to you Geri.

Regards
Graham
1hotBUSA
2000 Suzuki Hayabusa Red/Grey Bog standard except for bling and a kanooter valve. Oh and a turbo kit on the floor.
Strike a blow for freedom...Smash a speed camera!!!
Red Bikes Rule!!!!!<i></i>