is regular fuel ok for the LS1 engine
Originally Posted by Fishv12
Bad gas causes carbon deposits that needs a hell lot of work to get it removed. My other car required super and I just guess the previous owner used regular fuel all day long and it ended up with major loads of carbon buildup and the car couldn't pass emissions anymore.
Maybe I'm misinterpretting your post, but this goes against my understanding of gasoline octane. Lower octane gas burns quicker and detonates easier than a higher octane gas which burns slower and resists detonation when being compressed. Hence the whole reason for higher compression motors requiring higher octane gasoline. Nothing new there.
If one were to run low octane in a motor requiring higher octane (due to compression), I would expect a lot of pinging and damage as a result, not necessarily a deposit buildup.
But running a high octane fuel in a low compression engine will result in a deposit buildup, because of the slower burning nature and resistance to detonation of the higher octane gas. The engine's compression ratio doesn't take advantage of the fuel and doesn't burn it as complete. A lawnmower engine is a prime example (running 93 when it's designed for 87). Although I think the prime factor for deposit buildup is the quality of gas from it's detergents and refinement quality more than anything else. Engine design and how well the engine is maintained has a lot to do with it as well.
Originally Posted by 98TAauto
93 here is 2.07
89 is 1.99
87 is 1.89
89 is 1.99
87 is 1.89
$2.59 91
$2.49 89
$2.30 87
California and a few other states deffinatly gets the **** end of the stick when it comes to gas quality and price. A person with a 200+ mile commute per week and an LS1 powered car as the only source of transportation will probably fill up at least once a week if not more. The difference between 87 and 91 could be $300-$400 per year.
I think there is a common misconception that 87 octane fuel is "bad" fuel. 87 octane has a lesser flashpoint than 91, but that doesn't mean it is bad. My truck is right at 10:1 compression, but I will run 87 octane on occation. Twist the distributor a bit clockwise or yank the vacuum advance and I have no detonation issuse. Much the same as the knock sensors pulling a bit of timing when neccessary.
If you must run 87 keep your lead foot off the floor and if you have to pull a long hill, select a lower gear so you don't lug the motor down.
