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Re: [turbobike] jet kit for turbo carbs

Christer Johansson (christer.johansson@mbox383.swipnet.se)
Thu, 15 Apr 1999 19:00:35 +0200

Iīm not saying that itīs easy, but when Youīve got them right
hang on!
I would not recomend a plenum with a one side inlet, if You want
the inlet on the side ,I think You will have to do somethiung like Rickīs.
Or You could make it with the inlet on the bottom,
I will be using this type on my new setup.
Is it a Tb03? If so it will support a tad less hp than the trim 60,
but not much of a difference though, about 240-250 I guess.
The limiting factor on the Tb03 is the exhaust housing.
The watercooled 1074 motor is known to make alot of power.
I havent delt much with it ,but I belive itīs just as sturdy as the 1127
version, maybe better as the 1127 have some trouble with the crank
Dont try and use very high boost settings (about 18psi) with the Tb03
as it will produce alot of backpressure and the 1074 head has big valves
(31-27mm) and those big exhaust valves will "expose" the cylinder for
rest gases more easily. As for the compression there seems to be
many different ideas. It all depends on wich type of fuel You are gonna
use and how much boost. Also ignition timing and cam settings will
be of importance. And most importantly how are You gonna use
the bike?

Christer

george kalogeropoulos skrev:

> --- Christer Johansson  wrote:
> > Hello George
> > I did send a mail about 3 days agoo to this list
> > ,but it seems
> > to have vanished!
> > Thereīs no secrets in tuning CV carbs for turbo
> > ,just laws of physics.
> > You have to pressurize them right, I have a 1/2 inch
> > hose routed from
> > the pressure pipe (after the intercooler) to the
> > carbs ,connects beneath
> > the membranes ,thus eqalizing the pressure in the
> > carbs and the boost.
> > I also have a thin line routed from the pressure
> > pipe to the vent pipes
> > on the bowls, this "line" protrudes into the
> > pressure pipe (about halfways)
> >
> > facing against incoming air, thus giving dynamic
> > pressure.
> > Sort of "force feeding" the main jets. I used 162,5
> > main jets on the old
> > setup.
> > But it depends on how this pressurizing turn out,
> > wich mains You will need.
> >
> > I know people that has used 130 mains on 300hp
> > bikes.
> > I will send You picīs , probably will explain it a
> > bit better.
> > I also use stock springs and needles. My bike idles
> > just like a stocker,
> > much better than the Efi bikes I have seen. As longs
> > as Your carbs
> > are tuned correctly ,there is no advantage in EFI.
> > Mark Moisan used 36mm CVīs on his 429hp GSXR.
> > The plastic lids on the CVīs can crack if You go
> > wild on the boost (+20psi)
> >
> > or get a backfire, I have had no problems though.
> > You asked earlier about the data on My old Garrett
> > T03, it was trim60
> > A/R ,48 in this size it will support about 270hp .
> > Port the outlet and fit
> > the
> > biggest possible wastegate valve and it support
> > about 290-300hp.
> > There is no idea to use a bigger A/R as the narrow
> > sector is in the
> > turbine wheel itself, bigger A/R would only yield
> > more lag.
> > You could also separate the wastegate and the
> > turbine and run twin
> > exhaust pipes, this would give even less
> > backpressure.
> > If You want more power than this You will have to
> > use a bigger turbo
> > like the T04E, but then you You will have to use a
> > twin flow exhaust
> > housing ,otherwise there will be to much lag.
> >
> > Hope this helps / Christer
> >
> > george kalogeropoulos skrev:
> >
> > > Now what's the secret behind jetting the stock cv
> > carbs with a turbo?!I
> > > haven't been able to get some real info on what
> > people are using to do
> > > this....is it some kind of jet kit?Who makes the
> > heavier
> > > springs,needles,jets.Everyone is saying that these
> > parts where modified
> > > to work?Can someone give me some real info about
> > this???This has been
> > > tormenting me for the last few nights!My friend
> > says don't bother with
> > > carbs.Christer seems to have this system running
> > really well.Will the
> > > bike idle properly?
> > > Thank guys :)
> > >
> > >
> > _________________________________________________________
> > > Do You Yahoo!?
> > > Get your free @yahoo.com address at
> > http://mail.yahoo.com
> >
> >
> >
> >
> Hi Christer and thanks for the reply! So it should be fairly simple to
> jet the carbs...I have another question,what is the best setup for the
> intake manifold?One inlet from one side of the engine or two pipes
> going on each side of the motor to the intake,something like Ricks
> intake but using carbs?
> I am going to use an intercooler that my friend is going to weld up.I'd
> like to see your setup on some pictures.The turbo comes from a dodge
> 2.2 litre engine,it is a Garret T-3 50 trim 48 a/r,how much power do
> you think i'll have?Don't forget i'm using stock internals,stock
> compression...How much can it handle?
> Thanks Christer!
>
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