thireshan said:
with regards to the airflow up top,car is standing on a dyno so wouldn't
that be the reason for the engine not sucking enough air compared to driving on the road?,if not,would a drop in filter(K&N or BMC) be a good place to start with intake upgrade or will software be the answer?
Quick tuning lesson
An engine is really super simple when you break it down.
1. Open can
2. add air and fuel
3. close can
4. spark
5. BOOM
6. Open Can
7. Remove exhaust fumes
8. Close Can
Rinse and Repeat
In its simplest form, "tuning" an engine simply does 2 things
1. optimizes the AFR (Air Fuel Ration) and,
2. allows more air and fuel into the "can"
- More Air and Fuel = More power
- AFR ranges from rich to lean where rich is safer and less economical and lean is hotter and more powerful (and dangerous)
Now that you know the basics, what does this mean for tuning the M3?
Well.. for starters the stock fuel pump is good for delivering fuel at up to 600RWHP (with race gas) which is WAY more than most will ever need. Over 400RWHP you will need to upgrade your injectors to deliver more fuel to the cylinders... so fuel delivery is not your issue
That leaves Air. Now de-catting helps SLIIIGGGHTLY as it helps the removal of exhaust gasses and cooling, but without flowing MORE AIR into the cylinders, you can tune till the cows come home and you wont get much more power.
That leaves induction and there are 2 ways of improving it
1. Timing
2. Increased Airflow
1. Timing... it sounds like wizardry but all it means is the intake valves are open for longer to allow more time for air and fuel to enter the cylinder = more air/fuel = more power... simple
2. Increased airlow. This is where you need to choose NA or FI (and btw NOS is FI as it simply adds more oxygen in the form of NO2 which allows more fuel to be added)
SO.... in summary, until you optimise airflow, you can remap but it will be a bit of a waste of money and effort as you are still dealing with the stock airbox and setup which is fairly well optimized already
Add a performance filter and the DME will notice the higher airflow and add more fuel = more power
If you tune on top of a new filter your will notice really nice gains... of course adding compressed air (Supercharger/Turbo) is the best, but that starts to get very expensive
Does this help??