I just purchased a '65 coupe that has a 351 Cleveland w/auto transmission. Everything runs fine at idle and when ran under normal conditions. Starting the engine cold will somtimes result in it shutting off, unless I give it some gas for a few seconds, but overall, it runs pretty good. But out of curiousity, I wanted to see how much torque the thing had so I pushed it hard to feel the power. First time, I was cruising about 40 and once I gave it the gas to go, it made a pop pop noise (not sure where it came from) and the power froze, and I smelt some kind of smokish smell. Let off the accelerator a little, and it ran fine again. It did this a few times I tried, with about half the attempts being successful and giving me the power I was looking for. So to test it some more, I tried it from a dead stop. This attempt only left it with the engine shutting off instantly. Now, I don't plan on riding the thing hard like this often, but it does make me worried that something is definately not right here. I'm not much of a mechanic, so any help would be appreciated. Does this sound like a serious issue, or just something that might need to be adjusted? Also, seeing as this is the first old car I've ever owned, what grade octane gas should be used in an old engine as such?

 

I had the same problem. Advanced the timing and it went away. The type of gas depends on your compression ratio. If it's an unmodified Cleveland I'd run regular.

 

Depends on the heads for compression.. the 70 4v heads had small chambers and need race gas to run right. Later 4v heads like 72-74 will run on regular. 2v heads should run fine on regular no matter the year they were made as they all had larger chambers and werent really considered a performance head.

Have you swapped the valvesprings yet? Stock springs are rather weak, couldnt hurt to change them. Other than that its timing and fuel, just gotta tune it so it does what you want when you want to do it. How takes alot of time and space to write, its best to read up on tuning in books.

 

Thanks for the tips. I just bought it Friday, so I haven't had a chance to do much with it yet. I'm not quite sure which year model the 351 is, but I do know it's not stock. I'll give these suggestions a try, and hopefully get this issue resolved soon. Thanks again, and anymore suggestions are still welcome.

 

I would run through two or three tanks of gas before I did anything to it. It's amazing how sometimes these engines fix themselves, especially if they have been stored and not run very much. You could have some carbon build-up that needs to be blown out, or any number of little things that add up to your current problem. Now, if it did it every time, there would be some fixes, but since it doesn't, I would just drive it for awhile before I did anything. Make sure all the fluids are fresh, and that all the filters are fresh.
Here are some other things you might want to check. http://auto.howstuffworks.com/framed...ewtrouble.html