MPG drop?

[S77CCP]

I'm currently running a 172 FF on Super unleaded which returns around 38mpg, the car is off for a upgrade to around 200bhp, how much of a drop in mpg can I expect?

 

[edde]

Depends who if you use the extra power won't amke much difference realy as a decinet 200hp upgrade gives you extra low eng power so you chnge up earlier etc so it would even out.