When I recently tuned up my 302, I noticed the ignition timing was set to 14 BTC. The factory setting for this on my '77 is 12BTC. I did not worry about changing it because I know that advancing your ignition timing is one thing to increase HP. However, recently I have been using the car as a daily driver and the gas mileage has now become a concern. I have heard rumor that when the timing is too high pinging or high gas consumption is a problem. Well it never had a pinging problem but I am thinking maybe that is why my mileage is bad. Does anyone have an opinion about my timing setting?
Personnaly I don't think that extra 2deg would adversly effect your mileage, did you check the total advance to see what it is? I am going to guess that maybe because your engine is a little more peppy at that setting, you are getting into the throttle a little more agressively and this is always a mileage killer. Of course there are a bunch of other factors that could come into play also, just have to do a lot of trial and error to come up with a happy medium. Try the 12deg setting and drive a tank full to check that mileage against what you get now, change spark plug gap and try it again, if all else fails, spend the few bucks and have it put on a scope. Almost forgot, how old are the ignition wires? Just my 2cents worth.
I think you are right that I am using the throttle a little too much but i try to take that into consideration. I have replaced my spark plug wires, spark plugs, the distributor cap and various other small things just recently. I believe the gas mileage has improved a considerable amount, but I believe it is still too low. I will try different things. Do you think things like wheel bearings will help?
I have another crazy question. I went to change my ignition timing and could not figure out how to get to the bolt used to loosen the distributor. It is in a tight area and with the wrenches I have in the shop, I could not get to it. Does anyone else have this problem. If so, how do I get to it? I am not sure if I need a special tool or just some knowledge.
david, i've never had a problem as long as i used a distributor wrench, they are available at any parts store, like pep boys. the wrench connects in the middle and can be offset to go under the distributor cap. hope this helps.
oh that helps alot thank you. I will hopefully get down to pep boys today to get one. You see I never changed the timing on my maverick. However my dad's truck has points so I almost always had to re adjust the timing on it, but for some reason I never had a problem getting to the screw.
A distributer wrench would be handy, but with a couple of bruised knuckles, a lot of swearing, and dropping the wrench on the ground, I have managed to get to the timing bolt with a standard wrench.
Am I the only one that doesn't have any trouble getting to the distributor hold-down bolt with a regular box-end wrench?
I use a regular craftsman 1/2 in. wrench and have no problem either. Althought when the A/C was on it was a little bit of a pain. Also the gas line runs right in the way. Hey you know guys we can't complain to much because those chevy guys out there have to go all the way to the back of their motors to get to their distributor bolt. HAHA
I think if I did not have a/c, I would also be able to use a regular wrench, but I do have a/c and the compressor gets in the way.
poor mileage Some things that effect mileage also, is dirty or poor quality air filter, and a restricted/plugged exhaust system. How old are they and does the exhaust system look a little small for the engine you running now?
Sorry for the late response. My exhaust system was just replaced. I ran dual 2" pipes out the back. (it was a pain because I had to run dual cats on it!) The air filter I replace often. I went to autozone, pepboys, and napa. All of then kept trying to give me this little piece of crap they said was for my car. Its diameter was right but it seemed too narrow. I went to carquest and they provided me with one that was twice as wide! Oh a
I had the same little air filter on my 77 when I got it. I replaced it with one of the taller ones, like was on my 76 Granada. The book always did show the little short one. was it the Fram 3424? I dunno, been a while...
well the one that was too small was the fram, but I never looked into buying another fram. The one that finally worked was car quests own brand. I stock piled them when I found them.
