Turbo bike carbs

[pork]

Jus something I was wondering, as an exercise in theory

, has anyone tried turboing bike carbs on a ma engine?
I've read that uncle bobs bike turbo guide a few times, understand the plenum idea , And pressurising the floats, what else would be needed?
Turbo size?
Fuelling?

Anyone know of any decent links I can read through?

 

[pork]

So, from what I understand, I need, bike carbs with plenum and pilot tube incorporated. Pilot tube is fed to the vents on the carb floats. Fuelling wise, I'm gunna need fuel pump which is capable of higher psi than my turbo, return feed to the tank, and a boost referenced fuel pressure regulator.

How does the boost referenced fpr work exactly? Would it need a feed from the turbo?

 

[pork]

Anyone?

 

[Skinner_87]

Hi Pork, the turbo fpr is the same as i use on my injected to carb conversion CG13 ,as far as i know i dont have it connected, but there is an inlet from the manifold (or plenum in your case) that adjusts fuel pressure dependent on manifold/boost pressure like the below:

http://www.fuelpumpsonline.co.uk/sytec-turbo-fuel-regulator-carburettor-32-p.asp

 

[pork]

Thanks, that's exactly what I needed to see, nice diagram that explains it simply, cheers

 

[pork]

Another question I need help with is, what do I do with the vacuum pipes from the brakes and advance? With the bike carb mani, I just fed it into that, but with a turbo, those will be pressurised, so there won't be a vacuum !?!? Or am I wrong?

 

[frank]

its neater if you junction all your vacuum pipes into a block eh http://www.ebay.co.uk/itm/VACUUM-MA...CarParts_SM&hash=item56483f5f03#ht_1991wt_956
and a petrol turbo engine probably spends more than 95% of its life off boost (mine is running half a bar of vacuum even @ 80mph)

 

[pork]

Hi frank, does look very tidy, but (excuse my ignorance) where would I plumb it to? Surely all air going into the engine will be pressurised, so no vacuum? Or am I jus being simple

 

[frank]

its plumbed into the mani pork (downstream of the throttle slides/plates) and like i say, there will be negative pressure there for 95% of your daily driving

 

[pork]

Ok, cool, I understand you now,

 

[pork]

Would u need to do anything to the ignition system? What's available to an ma12?

 

[frank]

Would u need to do anything to the ignition system? What's available to an ma12?

you might want to retard it 5 or 10 deg

 

[pork]

Cool, the more I think about it, the more I wanna attempt it.

If I may pick your brain a tad more
How much difference in spacing between the cg and an ma? Looking at the glanza manifold that a few people have used?

 

[frank]

Cool, the more I think about it, the more I wanna attempt it.

If I may pick your brain a tad more
How much difference in spacing between the cg and an ma? Looking at the glanza manifold that a few people have used?

the bores are the same eh (ma12/cg) so the spacing should be close, but the bolthole positions are more important than the spacing tbh

 

[pork]

I'd have to weld on a new flange either way wouldn't I? Is there any other manifolds you would suggest that may fit better?

 

[pork]

Looks simple enough

 

[karlj]

When I was looking into this the plenum chamber in the second picture was the type I was concidering

 

[pork]

Yeah that's the sort of design I'm leaning towards too

 

[pork]

Jus another quick pondering, which engine would be best suited to this ma10/12?