Hey guys, just finished building my a12 turbo and I am having troubles getting it to rev, it seems to idle well but as soon as the primary jet squirts fuel in it dies. It doesnt seem to be a fuel supply issue because fuel pressure stays on 4psi and the needle and seat are closing, I have also played with the float level and it made no difference

heres the details:

stock a12
t28bb turbo
blow through setup
surge tank with facet lift pump
vl fuel pump and malpassi rr reg
weber 32/36 carby has had rebuild kit and have added boost reference line into float bowl

Any help would be much appreciated
Thanks

I may be wrong but the size of the carby may be too small to support a turbo that size on a smaller engine like the a12. I could be wrong... i havent really played with turbo carbys before.

But how does the engine act wen you open up the throttle? Does it cough n splutter? or does it ever so slowly rev up and then plateau?

Heres a pic of the setup

engine

It seems to die (as in engine wont fire) as soon as you press the accelerator pedal, and it doesnt seem to be turbo related because it still does it with the carby hat off, also you can look down the barrel of the carby and see as soon and the fuel is squirted into the primary barrel the engine dies

Nice and neat setup mate! I would start looking at the basics, check a blockage in the intake/exhaust track and fuel. Whats the behaviour of the engine when you rev?

Id try to shorten the float bowl reference line as much as possable and make sure its not tee`d off for any other purpose. Its just a guess But if there is any delay between when when the carb venturi gets pressure and the top of the bowl gets pressure the fuel wont flow till it balances out. Bit of a wild guess really!

Try and get hold of a wide band oxygen sensor. This will help diagnosis and will be needed to get mixtures right.

Keep us informed

EDIT: the referance line must go to the top of the carb/hat area. If its going to just after the turbo it will seriously flood as boost starts.

I dont think the carby pressures are the issue because i cant get the engine to rev up at all to spool the turbo, also the problem still happens when the carby hat is removed and the float bowl boost line is unplugged

sounds like lack of air or lack of fuel... maybe a line is crossed or put where its no supposed to be which cancels out the vacuum?

Timing? Cam or ignition that is?

Did you (or anyone else for that matter) build the motor or was it a runner before? Just wondering if the cam or ignition timing is out it will be very flat.
Even very rich it should still rev a bit, just chug a lot of black smoke..

Its suposedly idling fine...