Fuel Pressure for 20v.

Okay, so basically every time I took Rolla out, I need to pump in at least RM20 of fuel, even if its just to KL from Cheras (around 15km and 20-40mins when traffic is no good). Which is not good for my walletla in other words.


And it pops a lot of fire whenever I decelerate. Few friends told me that the car was running rich. And yes, my friend already told me that they set it to a bit rich so that the car will not have any problem when high revving. And I didn't even bother to checked the fuel regulator since I got my car back.


The new bay. Bling bling. Anyone noticed some new stuffs here and something that isn't right? I'll go into it later.


Until one weekend, the battery went flat coz I left the car for a few weeks (I'm in JB mah!). So called a friend of mine, Bakat (or in English it is translated to 'Gift' haha) to jump start my car. And since he is kinda an automotive dude, he suggest me to check the regulator and told me to do some Googling to find out the standard fuel pressure for the 20v Blacktop.

Behold, something that you need for the Blacktop. At leastlah. An adjustable fuel regulator.

So we popped the hood and took the reading, guess the number? 5 effing bar! Hahahaha. And after some Googling, found out that the standard fuel pressure for 20v Blacktop is 2.7bar. That is more than double yaw! No wonder the consumption is soo bad.


Okay so some info from a 9000rpm forum, we knew that:

For 20V Blacktop
Std pressure is about 2.7 bar or almost 40PSi. Here are the results :

48 PSI (3.3 bar) - There is a def increase in bottom-mid range torque but acceleration high up is slightly slower.
50 PSi (3.44 Bar) - Greater power increase in the bottom-mid.
52 PSi (3.6 bar) - Huge increase low down but the car almost hits a brick wall at about 180kph.
42 PSi (2.89 bar)- Slightly higher than stock and small diff in the mid range.
44 PSi (3 bar)- This seemed to be the sweet spot with the stock ecu where the bottom?mid range power increased without sacrificing the acceleration or top speed. I love this setting and there is a def increase in torque in the low/mid range.

It must be noted as well that when the pressure is turned up the throttle response increases greatly as well. This was an added benefit. With regards to fuel consumption....i have not noticed any difference!  Another good bonus is that the higher pressure removes pinging on the engine. My car used to pig slightly under load below 2k rpm.....now it doesnt at all!

The next update will be with dyno graphs and power readings....BUt for now i recommend this to any 20v owner with the stock ecu.
So 5 bar was totally out of the list. And the probability for it to hurt my injectors were also high. So we detuned it to 3bar. Tested it and I don't like it coz there is no bottom power at all. Vtec kicked in after 3500rpm and was shitty below it. So uprated it a bit to 3.3bar and still no bottom power at all. There is no surge of power when I need it. Yes it saved fuel but it doesn't suit my taste.


Been driving with the 3.3bar setup for awhile, until last week when I fitted in the trumpets, I adjusted it again to 3.5 bar. Results? Awesome improvement. Vtec kicked in early at 3000rpm and the mid range power is still there except for high revvingla. The highest I tried is 6500rpm at 170km/h. Didn't have enough balls to press the throttle anymore after that.


Conclusion, I'm gonna stick to 3.5bar setting for now.