Zman

I'm almost done buying a 1.8 Beta engine (right now I have the 1.6 Beta) and I'd like to know if I have to change the ECU as well. I mean, theorically the ECU compares throttle position, rpm, temperature and other inputs to tell how much fuel is injected and the advance timing, but what I don't know is if the changes would be dramatical as to have to change it. I know the 1.6 uses the same intake (and exhaust) cam as the 1.8, and I'm almost sure the injectors are the same size.
TIA

[ April 11, 2002, 10:15 AM: Message edited by: Zman ]

Brendan

but is the timing the same? is the fuel usage maps, the sensor input all the same? no they are different, and we don't know if your ecu can be remapped into 1.8 L more, hence why you should change the ecu. Honestly WE don't know since I've never seen a 1.6L beta in person.

Zman

Yes, in fact, thats what I meant, if the cams are the same, it means intake and exhaust valves remain open the same amount of time (therefore, admited air is limited by the volume on the cilinder, not period of valve open) and overlap is the same also. In that case, between first stroke (down-admission) and second stroke (up-compression) the time is the same, AND the piston reaches Top Dead Center in the same amount of time, so ingnition spark should be launched at the same timing... or not?
What I mean is, there could be minimal differences, but I could use the car keeping my old ECU (OK, maybe not at peak performance) WHILE I get the money either to get a new reprogrammed ECU, or a stock unit for a 1.8
What do you guys think about it? Random? Red? Brendan?
rolleyes.gif