i have a sierra sapphire that was converted with the 24v boa engine a couple of years ago and it has been running very under powered and i have tried numerous things and have came to the point where i dont know what else to do,

it has the egr system removed

an after market alarm fitted with engine start button on the key fob (doesnt really work that well)

has manual type 9 gearbox with lsd

modified stainless exhaust with rear silencer no other silencers

no other mods, everything else is standard, injectors, cams etc

first thing i done was changed the inline motorsport fuel filter with a new one, didnt do anything

then i changed all the air flow sensors, didnt do anything

changed the complete air manifold, didnt do anything

took the manifold off again and changed all the injectors and fuel rail including the fuel pressure thing on the rail and cheaked the wiring for injectors, didnt do anything

took the petrol tank out and cheaked pump and it was perfect and no dirt in the tank, all the fuel lines are not kinked or squashed anywhere, it is the 2.0 twincam tank with twincam pump

took the crankshaft sensor off and cleaned it, didnt do anything,

the car is running on super unleaded and recently put octane booster in it aswell incase it was shit petrol but didnt do any difference.

thought the middle silence was mabye f**ked and holding it back so took it out and put a straight pipe on it which just left the back box, very loud now but still goes shit,

all the parts i used was taken off a standard granada cosworth boa that i knew was running perfect so knew everything i took off it to try was working how it should, i bought the car with the conversion already done,

it has an lsd and escort cosworth wheels and it will spin in first but not second that well, and thats in the wet, i have 2.0 twincam sierras and they would sit with the v6 no problem thats how under powered it is, it is firing on all cylinders and i put new plugs in it when i bought it, they were just standers ones out of my local motor factors.

engine isnt smokey and has good oil pressure and doesnt heat up or pressurise, knock or rattle anywhere or choke out at the end of the road,

only other thing i can say is that when you drive it in any gear and you put your foot down it just doesnt want to pick up and go the whole way till it eventually reaches the limiter, you can nearly feel it giving a nudge now and again when you are accelerating it through the gears as if it wants to give full power but you can tell that somthing is holding it back. my standard auta granada cosworth would eat it for breakfast.

getting very pissed off with it now to the point i dont even want to drive it so if anybody on the site here has experience on these engines or any tips on things i havent tried it would be very helpful,

also i am from northern ireland and i dont know many poeople over here that knows much about them as there isnt that many of the 24v sierras as in england that i am aware of so any help is appreciated guys,

thanks for reading!