Here are afew tip for those of you tuning your naturally aspirated engines
1. Tuning N/A engines is all about getting the air in and out of the engine best as possible with little flow restrictions and well thought out and designed add ons such as air filter kits, exhaust systems, manifolds and mild head work.
2. N/A engines will work alot more efficiently with a higher compression ratio (C/R), ways to achieve this are simple at first then become very exspensive! but sticking to doing it cheaply you can have the cylinder head face skimmed to its max markers or just before for safty, this will give noticable increases in economy, bhp and above all,,,,torque.
3. Use a good qualitly engine oil!!! very important for performance and engine life, thinner oils give engine more bhp due to having less friction, thicker oils seal combustion chambers better for better compression on old or older designed engines giving improved running and power.
4. Once modifications have been done to your engine get it set up with an adjustable fuel pressure regulator to give the extra fuel required to make more power from the added airflow of filters and exhausts, most ecus will only have minor correction factors to deal with added flow, on some cars just an air filter will upset the standard map due to the added flow, and a map sensor will have no idea you have increased the air flow into the engine so it will keep functioning the same leaving the lambda to see a weak mixture and constanlty running on mixture adaption maps in your ecu,,,,,this isnt an ideal tuned state trust me.
5. get as much cold air into your engine and try to make it so the air isnt heated up much on the way into the engine, this will give great figures,,,,,a test was done on a mondeo st220 v6 with the standard airbx and filter with good cool air supply,,the the result was 226bhp, swapping it for a green cone filter in the same place lost it 4 bhp!!! a simple pannel filter gained 3bhp and a full CDA airbox kit gained 8bhp!
6.DONT just turn your fuel pressure up on an N/A! turning the fuel pressure up on a failry standard engine will kill power, its unknown to most but rich mixtures loose power and weak mixtures gain power (within limits) so dont do it, signs of rich mixtures are black smoke, poor acceleration and bad fuel economy and this will ulitmatly leed your engine to its grave by washing oil of your bores!
7. A quick tip if you fit a fuel pressure pressure reg, find out the cars standard fuel pressure and set it to that!!!, the way a vac pipe equiped pressure reg works is to richen the mixture quicker than a standard item not flood the engine with fuel all the time meesing up all the correction factors!
8. For ultimate power and revs fit lighter internals and high compression pistons, its costly but if your seriuos about n/a then its the way to go!
