Hello everyone I have a 03 sunfire ecotec 5speed. I recently discovered the fact thae this happens to be a 10:1 engine so I got to thinking that I'm running 87 octane in it that just shouldn't work unless the timing is incredibly retared or I am. So I am just wondering if there is any way to advance the ignition timing to help performance perferably just enough to not have to run really expensive fuel. Thank you for any advise.
you need to learn more about how engine work. I'm not being a d**k. What I mean is that you can have a 11:1 compression engine running 87octane no problem and having a 8:1 compression engine that need 91 octane. Engine desing will do alot in detonation and the need of high octane gas. IE the Quad 4, the real one, the 2.3. 10:1 and it need 91 nothing less. The ecm for the eco is program correctly and it's not backing the timming if you run 87 octane. if you run 91, the ecm will not advance the timming.
the ecm is program to run safely on 87. if you buy a stand alone or a piggy back system and advance the timming, you'll have to run higher octane gas. It's not worth the $$ and time on the dyno to advance the timming. it won't give you enough for a street car.
Gilles
2.3 Ho
the PCM knows best, it can advance timing up to 50 degrees. this is any computer controlled vehicle, and i have seem it on scan data on a mac mentor.
CAR GODS MADE THE 1.6 SOHC TO MAKE US 2.2 OHV GUYS FEEL BETTER.
Does that engine have a knock sensor? If your motor is detonating and "will" knock down the timing. So it is safe to run a lower octane. But if it doesnt have a knock sensor.. no good
the engine/ecm are made to run 87. the eco WILL NOT gain anything if you go with 91+ octane. the Ecm has a preset timming curve and it will not advance timming as much as it can by itself so it's useless to use 91+ octane. stick with 87.
Gilles
2.3 Ho
actually the engine is programed crappy for power
take the late model neon rts engine versus the regular neon
ran 91octane in the r/t and put out 150hp while regular neons had 130 hp and ran on regular
