Hi.. i would like some info on turbo charging with twin su using the blow through setup. Is it possible?

I have heard ppl saying it wouldn't work.

The carbs i'm using aren't exactly su's to say they are stormberg 1" 3/4.

thanks for the info.

i've never heard of anyone doing this - and there's probably a reason why.

still it would be interesting to know.

anyone?

well i have been searching and found a little sumtin.

Su turbo

The way i see it; turbo charging just brings in more air and a faster rate.....and as the air enters the carb the piston will be forced up as normal and fuel will be delivered according to that amount......the only problem that may arise is that, the turbo forces into the air and a faster and denser(if intercooler is used) so in theory more air will be passing and the piston might not be able to 'read' it.......so if u turbo charge with a SU carb you would have to use different needles(jets) that will give u more fuel and low, mid, and high speed.Or even modifing exsisting jets to make them larger or smaller to get a perfect fuel ratio to the amount of air enter the cylinders.

what you said is quite likely true, but thats exactly the same case with every carbie out there, and exactly why injection is much more suited

im not saying go injection, im saying theres ways around it, im blowing into a carb at the moment (32/36 webber) theres no reason you cant do it, theres also a member blowing into twin webbers

the only concern would be how much boost you can use before the seals start to blow out and let fuel mixture out into the engine bay, you need to find someone who has an idea of this pressure (im not sure about the SU style where exatly it would leak)

and then if you want to use more boost than this you will need to box the entire carb(s) to level the pressure inside and out of it in order to stop the seals blowing

it has been suggested the 32/36 can take over 10 psi boost without problem, im doing exactly that at the moment 10psi with no box

ive also run it through a stock carbie with the entire carbie boxed, i had it at approx 7psi but the previous owner used upto 15psi i believe this way

[edit] dammit my nutri-grain went soggy

They would have to be contained in a sealed box to make it work I think.

I dunno, maybe you can take the carbies off the inlet manifold and make a plenum chamber, bolt it to the inlet manifold and bolt the 1 3/4 Stromberg on the inlet of the turbo and make it a Sucko carby turbo setup.

I have often contemplated this also I had an idea where I could weld on injector mounts onto the inlet manifold at each port seems like a good idea.

An SU is a CV(constant Vaccuum) carb. It relies on the vac of the engine to lift the piston. If you pressurise the lot will it not force the piston down/closed? I don't know, just food for thought.

Sell the SU's and manifold to fund the project. . . ok, keep them on a spare engnie.. .

Quote:

IT would work like a MAP sensor use the 'absolute pressure' from the manifold to the SU carb.


Isn't their vaccuum with in the inlet manifold when the gas is applied?

ps. all it needs is some sort of vaccuum to pull up the piston.su

true, but only until the turbocharger starts spooling, in which case vacuum turns to +ve pressure.

maybe if you could get the vacuum from in front of the turbo...but then you might as well put the whole carb there.

oh well get a 32/36 or twin webbers

pro-240c stop encouraging suck through