Hi

A work mate "Robin Hood Owner" is having major problems with his car
basic setup is 2.1 pinto, stage 3 head, twin 45's, standard ignition
the car has been used for 3-4 years and has all of a sudden developed a problem

The car will run very smoothly up to 4k
and with gentle throttle application will rev to 7k when the rev limiter will cut in

but on medium to hard throttle, the engine splutters, and will not run very well at all, and very flat

things we have changed
plugs, leads, dizzy cap,earth straps(they were dodgey) and coil
both carbs rebuilt and blown thru, but we have pretty well discounted a fuel problem

also overcharging is not the cause as per my posts on a very similar problem earlier this year,

regards

steve

couple of ideas

you didn't mention the timing, could be a fault in the dizzy, also is the compression good in all the cylinders.

Hi-Steve. .could there be a fuel filter in the pipe line which is partly blocked allowing fuel through when on low to medium throttle, but not enough for full throttle. Jacko.

sounds like accelerator pump not werkin

I had a Fiat 127 Sport with the same problems - it was a dead sparrow in the air intake pipe before the air filter!

Once the air demand exceeded the little corpse induced reduced capacity, the engine misbehaved. I replaced almost everything before I checked the stupid things

Sorry , no photo of the dead sparrow