Tried a few tanks of regular gas--and it runs better.

Since gas prices are going through the roof, I decided to run a couple of tanks of regular
in my '74 MGB roadster and see how it ran. I've always used premium, though I'm not sure why. I was expecting to get engine knock or pinging (pinking) with regular gas.

My car normally runs on a little when I shut down and it always backfires or 'pops' especially when slowing down quickly.

With both tanks of regular gas now run through the system, not only do I not have any knocking/pinging at all, but I have had noticeably fewer backfires or pops, in fact almost none at all over the last two weeks of both city and freeway driving -- about 300 miles.

I like it: Cheaper gas and it's running better. Any idea what's going on here? Now if I could just find some of that 1970 35 cents a gallon gas, I'd have all my fuel problems licked.

Hmmm. A sharp contrast to the thread about octane booster.

Absolutely. I've poured in a few tanks of various brands of octane "booster". My feeling is it's a can of gasoline. Never seen any performance difference at all.

I'll have to keep running regular gas for a while longer to really be sure I've seen the improvements I've mentioned. But, so far so good. No negatives to report at all. Now, if regular were just a buck or two cheaper than premium, I'd be really happy.

It is a buck or two cheaper. Than here! Paid $5.60/USgallon yesterday.

I have always used regular gas with no ill effects. It's not as though we are running high compression engines; well at least most of us aren't.....

You were probably a bit retarded anyway while using the premium. (nothing personal, lol)
How about going back just a couple more years for that 100 octane at Clark for 29.9 cents per gallon?
RobS.

I use regular unleaded in my 76 B and have no issues, get about 28 mpg. Only fuel additive I ever used regularly is dry gas in the winter (not in the MGB - it's asleep all winter). It gets REAL cold in Buffalo.

When I bought my first new car in 1986, I could fill it up in Massachuetts on super unleaded for 89.9 cents a gallon. Yeah...

My "B" is a 1975, I've always ran regular with no problem. I've recently changed carb from ZS to Weber 45MCHH, still using regular and running great. Thought I'd try mid-range 89 octane to see if any difference after running regular through new carb, no difference. I'll stick to regular.

I've gone on a few runs with guys who insist on finding that Sunoco station with the high octane gas, funny thing is, they are the guys that seem to have the most running problems with their cars.

Keith, I'm not a big bling fan of braided lines and alloy covers, but that engine room of yours really pulls it off. The blue and the braided/chrome really looks good.

Unless you're running 10:1 compression with an iron head, premium gas is a waste of money. No factory MGB had anywhere near that and the later ones were lucky to reach 8:1. MGB's were designed to run on crappy gas, so that's where they run the best. Modifications make this null and void.

My only problem with low-octane gas is that it burns a little hotter, as does unleaded vs leaded, plus I have 10% ethanol added here, which burns a little hotter still, so I worry about valve seat problems. Anyone have thoughts on that part of the trade-off? The performance difference is small, a couple of mpg better w premium, less than the cost differential.

Hey Wray,

To be honest I wasn't a big fan either, but once I put the new carb on the more dingy the engine bay looked and as I got into it the more it sort of grew on me. I tried to keep some sort of logic to it by just using the braided hose on fluid lines. Then an engine bay cleaning was in order, then paint, then the engine and so on and so on and so on. I just wanted to get to the point where I wasn't ashamed to open the hood at meets etc.

Thanks for the compliment. I just finished up installing the rest of the hose ends and now it's done........... no more tinkering ...........I promised my wife, but she knows better.

My old MG needed premium, it would run on pretty bad with regular. Don't know why. I tried regular as an experiment after I used some regular gas from my lawn mower can last week and didn't have any problems, and I continue to not have any run on or pinging.

John Hamilton Wrote: