Alright. I have been running 92 octane since I got my car. Now, granted, I have a heavy foot, but I have also been getting about 10 mpg. I think that is bad. I was broke this week, so I filled up with 89. Alright, after 2 days of endless knock, it appears the knock has stopped (knock sensor shot?). Ok. Well, I hit my trip odometer when I filled up. That was 59.7 miles ago. I have used about an 1/8 of a tank so far...Now, dont we have 15.5 gallon tanks? If so, I an getting about 30 mpg...that CANNOT be right. Someone please point out my error, cuz I know its there...If info not here is needed, lemme know! Thanks!

 

If you ride is like mine, as well as many others, you are just experiancing the typical fuel gauge problem. For instance, If I top off when filling up, and highway drive, I get 100 miles before the needle even reaches the full line, and another 150 miles before it shows half a tank. Then it only takes about 50 miles before it goes down to a quarter, and 30 miles before it reaches the empty mark. I've made it 30 miles on "E" before I filled up-I know bad for the injectors, but I had no choice!! Anyways, a friend told me it was because the way the gas tank is made, larger volume on top then shrinks the lower it goes. This could be the reason it may seem that you're getting 30 mi to the gal. run the tank down a little further, and it should start to average out. Also, if you've only measures your milage from half a tank, this could be the reason it's only coming out to 10 mi to the gal.

Generally, before I bought the Thermomaster chip I'd get about 23mph highway and about 17 city. Know that I have that d@^% chip, on top of the cold weather, I get about 18 highway and only 10 in the city! The only thing the chip is good for is keeping the engine cooler, which is great for summer, but sucks in winter!!!

 

That is exactly what happens with me. Yeah. Also, I figure gas milage by dividing number of gallons need to top off by number of miles since last fill up, not by using gauge...It just seemed like I was getting good milage, so I guessed today using gauge...Thanks

 

Oh brother, the 305 TBI will RUN on 87octane without problems...

87 has the same detergents as Premium. Unless you have a high performance, compression/big cammed motor, which you do not, you are wasting money putting anything more than 87 in it.

 

I don't mean to be a smart a$$ FRMULA, but the 305 TBI has a descent compession rate of 9.3:1. You are right, Premium is not required however, it definetly makes a difference. Runs a lot smoother. My L03 runs MUCH better with premium; add descent quality octane boost (5-7pts), and there is actually a small SOTP difference. Granted I run a Thermochip and maybe it is effected more with using the boost than the stoch chip. But maybe BUCK268 is running one as well....which requires Premium. All I'm saying is that you shouldn't jump on Buck's case for using premium....if it works for him, let him go with it.

 

92 does give more ooomph. Its noticeable. Is it worth it? Its up to the individual. I put 89 in unless gas gets cheap like it does every now and again. I also put 92 in when I want to give it a good floging once in a while.