had a great rolling road session 11bhp increase but after we got home the car aint started since theres fuel and spark and its turning over fast enough but it wont start ,before it went in it started on the button and ran mint so is the 11bhp worth it or is there something wrong ive not pick up on

in my humble opinion must be timing..

what did they do with the jets..

unless they upped the main jets to much and its flooding..

Are you trying to start it using the choke ?

If i use the choke on my pinto with bike carbs it will not start i just turn the engine over a few times then press the throttle one or twice

Which RR did you go too?
I think it maybe as Graham said,dry the plugs and try it without the choke.

I had a similar problem when i fitted bike carbs to my 205 Pug only liked to start on half choke and ou could almost knock the choke off straight away and keep it running.

If the plugs have been wet then it may be a waste of time drying them out . Sometimes the only answer is a new set of plugs

Yup I had a similar experience ended up with one grade hotter plugs and switched the cold enrichment off