my car has a 9:1 compression ratio.what octane of gasoline would be the best?
2006-12-07 06:40:22 · 3 answers · asked by El Nueve 2 in Cars & Transportation ➔ Maintenance & Repairs
regular to medium grade gas should be fine. unless this a modified engine, check your owner's manual for recommendations.
2006-12-07 06:50:15 · answer #1 · answered by badbill1941 6 · 0⤊ 0⤋
Compression ratio is not the only consideration for determining what level of octane is necessary.
A stated "9:1" compression ratio is not necessarily correct. If the pistons, head gasket or head has been changed, the compression ratio could be quite different. Even if the engine is factory original, production tolerances could alter the ratio from the specification sheet. Also if the combustion chamber has deposits this will change the ratio.
The camshaft, fuel/air mixture, turbo/supercharging and altitude also have a significant influence on octane requirements.
Therefore I would try the lower octane gasoline first and see if the engine pings or loses power. If the answer is yes, increase octane until these problems disappear. If these problems do not disappear with the highest octane, you have a problem.
2006-12-07 16:58:45 · answer #2 · answered by db79300 4 · 0⤊ 0⤋
Regular. If it knocks or pings a bit under load, such as going up a hill, then go to the next octane rating.
2006-12-07 14:52:19 · answer #3 · answered by Anonymous · 0⤊ 0⤋