Bogalu

The engine inside is a replacement. Isn't new but was running fine for the first month I had it. I do believe I have an accel brand coil. Though I really want to try and spray some carb cleaner. I thought it was the coil when I started having my carb problems. So I replaced the coil. Didn't help. Still kept it inside though. Got the new carb and it made a world of difference. But still have the problem Im having now. Ive messed with the carb quite abit with no luck. I really think It has nothing to do with fuel delivery because there is a tremendous pressure in the hoses to the carb. The engine has not had anymore then 3000 miles on it since I got it and got a oil change when it was put in. Also my gas milage is horrible. No more than 4 miles to the galleon. It was a lot better before that. It was at least near 10 miles to the gallon. So I can bearly afford to drive it now. I dont know how to tune for vacume advance or much of anything like that. Some tips would be helpful. I got a holley 670 double pumpstreet avenger. Im gonna try the carb cleaner trick first. It will probably be the cheapest route before I go and start replacing parts.

Daze

Have you put a timing light on it to check where the timing is set, I would start there. I hate to sound like a broken record but it sounds like your vacuum advance is not working. Your timing needs to become more advanced as the RPMs go up. If the vacuum advance is sticking or leaking the timing will hardly change as RPM goes up. Had the exact problem on my fathers 351W. I fought with the carb for a week before I did some other testes. First thing I did was pulled the vacuum advance hose from the advance and plugged it off. I then went for a test drive and there was no change at all that told me that the advance was probably the problem. If the car had gotten worse than I would have known that it was not the advance. I then put a hand pump on the advance and pulled a vacuum. In the case of my fathers set up the advance was just sticking and pulling a strong vacuum fixed it. Often times when a vacuum advance goes bad it will leek. This can be tested by hooking up the hand pump and pulling a vacuum while you watch the gage on the pump. If the vacuum does not hold than the advance needs to be replaced. If it does hold, put a vacuum gage on the hose going to the carb and make sure it is pulling vacuum when the motor is running. Do these tests and let me know what you find.

falconfixer

^Good advice - even easier than pulling the advance vacuum line and driving is - putting a timing light on it and seeing if timing advances when you hit the throttle.

Pull the plugs - is it running rich or lean?

ONE more thing to check - i have had a new/less than a month old Holley (albeit single pumper) start to run rich/bog on acceleration until the revs came up... Are the secondaries opening too soon? Not at all?

Daze

Good point, I said something similar in an earlier post but I don't think he has a timing light, so I presented plan B. When I was banging my head against my father's 351 I did not have my tune up kit with me and had to improvise and did the same thing.

Bogalu

your right I dont have a timing light. I want to try the vacum advance trick you told me but you need to give me the same instructions you just gave me but in the "beginners vacume advance for dummies" form. Thanks.

falconfixer

Still pull the plugs and report condition!

Standing BY.

Daze

I don't know how simple you need this so I am going to brake it down as simple as I can please don't get offended if it is to simple. You are going to need to buy or barrow a hand held vacuum pump make sure it has a built in pressure gage.

First disconnect the hose that goes from the Carburetor to the distributor at the distributor and plug off the end of the hose. Go for a test drive and take note of how it drives. If it is worse than pull over and reconnect the hose. If there is little to no change than the problem is probably in the advance. To check the advance put a hand pump on the advance and pull a vacuum. If it pulls and does not leak than reconnect and go for another test drive and see if it had been sticking. Often times when a vacuum advance goes bad it will leek. This can be tested by hooking up the hand pump and pulling a vacuum while you watch the gage on the pump. If the vacuum does not hold than the advance needs to be replaced. If it does hold, hook the pump on the hose going to the carb (do not actuate the pump) firen up the car and watch the gage on the pump as you increase throttle. If the gage is not showing any vacuum than that is the problem.. Do these tests and let me know what you find.

Bogalu

I just replaced my spark plugs a couple of weeks ago. The ones I took out looked fine and ran fine. I just thought some bosch would make a difference with the problem I am having. The only problem is I dont know what or where a advance and vacume are located.

Daze

The vacuum advance is the silver part, with the hose nipple sticking out of it, that sticks out of the side of the distributor and has a vacuum hose going between said nipple and the carb.

TexasAxMan

How do you "loose" power? I understand how you can "lose" power. Does that mean you "let it loose"?