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Porks bike carbs and boost project

frank said:
drive-by-wire throttlebody,s are pretty cheap neil :) and many diesels have a swirl flap too
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Controlled by pulse width modulation, so in theory an 'On' and 'Off' signal SHOULD give fully open and fully closed... They do run at sub 5v though so will need a voltage reg
Edit: QG and CR throttle bodies look cheap enough, and voltage regulators are only a couple of pence
 
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frank said:
drive-by-wire throttlebody,s are pretty cheap neil :) and many diesels have a swirl flap too
Click to expand...
That's a really good solution, so simple. Can't believe that no one thought of it earlier its so obvious.

Depending on voltages it might be possible to run it straight of the rev counter now that the transistor is in place.
 
l_jonez said:
That's a really good solution, so simple. Can't believe that no one thought of it earlier its so obvious.

Depending on voltages it might be possible to run it straight of the rev counter now that the transistor is in place.
Click to expand...
You want it open or close, no in between. But yeah you could, have a 5v feed from a voltage regulator to it from a relay controlled by a transistor (I'm assuming the throttle takes a bit of current at only 5v to stay open) controlled by the same circuit as the electro clutch
 
Cool! Il look onto this!

Had an hour between jobs and rain so whipped off s /c pipe to see this

ugememad.jpg


Gunna have to source somthing better.

Also plumbed up BMW mini idle valve, piston controlled by manifold vacuum , so acts like dump valve to, havnt driven it yet, but makes some cool noises jus revving it lol

juvegyba.jpg
 
Here's video off BMW valve lol




Been for a drive, hmmmmm

Need injection, or at least 3d ignition, there's no power when setting off even though there's 2-3 psi idle boost, my thoughts are is that beings there's pressure there all the time, the vac advance isn't being pulled

Then whilst driving is incredibly lean, AFR is all over the place! Then there's still that problem in higher revs every now and then when it leans out and goes all juddery :(

Jus uploading dodgy driving vid, everyone looks round at it whilst driving, noise is strraaaaaaange lol
 
Probably the constant change in pressure?
I assume that bmw valve allows vacuum in the inlet? But closes the moment throttle is pressed so instant 2-3psi boost. Carbs aren't that quick to respond :p
 
pork said:
Yeah, closes instant you put foot on pedal,
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So instant 2-3psi.. let foot off.. vacuum... foot on gently instant 2-3psi

Hard to explain by typing but its click 1 click 2 click 1.. in short spaces of time.. and carbs aren't known for fast responses :p

Injection needed as you say :)
 
On the plus side, I've never heard anything like it... was that popping on the overrun?
Maybe you can get away with richer needles/bigger jets and electronic ignition?
 
Yeah, popping with AFR reading 21 !!

I've moved the needles to last clip position, maybe bigger jets could help
 
Dont bother with a MAF, you will need a MAP for your setup.

You planning on swapping to ITB's or going back to a standard manifold with a single TB ( latter would be my choice)
 
I've got the itbs that fit straight to my manifold, was thinking of making a plenum and mounting the maf on that
 
Looks OK but I'd be worried that its a working unit? He claims it is and blames the loom? It might be true but the cash on collection has my negative side thinking its a bit suspect
 
Yeah scrap that.

Apparently (speaking to other dude) best one to get is ms2 with the ms2extra firmware (whatever that is)
 
Got jets drilled to 1.5 today, afr's loads better, but the spluttery /juddery thing whilst at wot is even worse :(

So **** it, gotta go injection, driving me mental !
 
Andy sent us a link for good gasket stuff, but rubber mat sounds good :)

Another chap on other forum says I keep blowing that gasket coz the throttle plate is after the supercharger and there's a surge when I close the throttle,

But I've fitted that valve that here, after s/c , that opens on vacuum.........
sase2yge.jpg


So shouldn't be getting a big surge when lifting off, probably jus weak cork type gasket I'm using
 
Noddie said:
cut one from rubber mat? or silicone bead left to dry then bolt up?
Click to expand...
Silicon bead would blow out, need somethibg flat with a lot of rigidity but that can be compressed. PTFE would be good if it didn't creep so much... rubber matt is a good bet :)
 
pork said:
Andy sent us a link for good gasket stuff, but rubber mat sounds good :)

Another chap on other forum says I keep blowing that gasket coz the throttle plate is after the supercharger and there's a surge when I close the throttle,

But I've fitted that valve that here, after s/c , that opens on vacuum.........

So shouldn't be getting a big surge when lifting off, probably jus weak cork type gasket I'm using
Click to expand...
You getting a spike on boost gauge?

I used a silicone bead from TB to manifold on the turbo car. tested to nearly a bar with no problem. 7psi isnt really that much pressure in reality.
 
Cheers people! :)


Whilst your all here, want some advice on what injectors to get, more to the point, what car to take them out off
 

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