Beggers20 said:
I dont mind being lectured lol especially when i know you are rite just that im trying to do it on the cheap so to speak. Spent nealry 600 on this now started off as a 300 quid project lol As for injectors i was told today at the Piston heads show by a tuning company that there wouldnt be much point in fitting the bigger injectors unless i was going for forced induction (if ony i had a spare 3g lol) He basicaly said thet the ecu is only programmed to put a certain amount of fuel into the engine and a lambda burn is the optimum burn that the ecu can set up so uprating them would be pointless? How much he knows about the Duratec v6 i dont know he seemed to know what he was talking about so im in 2 minds onw about the old injectors. Any help or lectures lol
No thats perfectly true, and he's the expert

!!
The 19lb green injectors fitted to the ST200 are a bit of overkill... in conjunction with the full works conversion to ST200 spec, and the ST200 ECU they do have a function... but like the guy said you dont need them at all really on a standard engine with standard heads and manifolds etc.
The standard injectors can squirt a fair bit of fuel into the engine anyhow, and i suspect that they err on the side of caution and actually squirt too much fuel in! (a lean mixture kills engines)
What he meant by lamda burn was the stoichiometry of the reaction inside the engine (when it burns the air & fuel producing the exhaust gasses) at the ideal point between lean and rich, and the lambda sensors in the cats and exhaust measure the amount of o2 so the ECU can adjust the fuelling accordingly to stop it from fluctuating either way too much. ( i think? thats how i understand it anyhow)
If you are tuning or upgrading your engine and you want more air going in, then you need more fuel to make more power, but also to stop the mixture from leaning out and making your pistons and valves overheat and melt. So your ST200 TB wont push things too far that you need bigger injectors! But if you wanted to get the most out of all the parts such as the enlarged ported cylinder heads, manifolds TB etc etc.. then they would push you to the magic 205bhp mark!!
The standard injectors can run at fuel pressures upto 100psi i think? ( im sure its theoretically whatever your fuel pump can supply??? i may be wrong though) so if you were planning a modest DIY turbo or supercharger conversion you can get more out of your standard injectors by uprating the fuel pump, and fitting an adjustable rising rate fuel pressure regulator valve to the fuel rail at the return end.
Then you could bolt on a turbo from say an extension of tubing welded up from the exit point of the exhaust Y pipe, have a wastegate actuator set to keep the turbo at a fairly low pressure like 5 or 6 psi, blowing the induction air through a small intercooler, and then up an induction pipe into the UIM (blowing through the MAF) as long as your new adjustable Fuel pressure valve was a 'rising rate' type one, a small boost reference hose plugs into it (same way you would connect a boost gauge) and it increases the fuel pressure by a set amount for each increase in boost psi... the ECU would also be able to sort out all the fuelling for you for such a low pressure setup, and you would have yourself a turbo'd cougar!!
Id try it first of course.. but!!!!!! hahahaha

it could all go horribly wrong and you would knacker up your car!
Anyhow im no expert, Jamie is the guy to talk to about anything cougar, and a fair few members on here are engineers and computer experts!!
I spoke to a tuning guy who specialised in mondeo ST24's and ST200's, and he said that the best real world tuning mod was to fit a brand new set of spark plugs, mainly because the platinum plugs dont just degrade and have widening plug gaps etc.. but they actually start to fail around the area where the ceramic insulator meets the metal plug body.. and you get a characteristic brown ring forming. That means that exhaust gasses are starting to leak between the gap through the insulation... so you're losing compression, and severely burning up your HT leads too... all of which leads to poop performance.
Get your standard fuel injectors ultrasonic cleaned and serviced with new o rings.
He also said buy a brand new MAF, just a standard one, and your car will fly... because they get damaged over time and gunked up, being a hotwire type they are meant to burn up any deposits that contaminate them... but it doesnt work 100% so a new one and a minor tune up and adjustment will see you getting the claimed MPG figures and also you get all the horses back, which will have escaped since your cougar left the factory!!
