69 440 detonation issues

Posted By: 440 4 me

69 440 detonation issues - 06/24/12 06:56 PM

I have a 69 440 that is fairly stock. It has a few updates/upgrades including an electronic ignition, Hughes camshaft (basically an upgrade over stock HP camshaft), forged pistons (flat tops) and Mopar dual plane intake. It runs stock exhaust and carb. I had it out for the first time in a couple years last night. I put fresh fuel in it (pump gas - 91 octane) and I added a container of octain booster. Still, it detonates when I accelerate. I have not checked the timing on it yet (I know, I need to do this) but I would think if I had it advanced too far that it would crank over hard - which it does not. Any suggestions would be appreciated.

Thanks,

440 4 me

Posted By: 440dart

Re: 69 440 detonation issues - 06/24/12 07:04 PM

Quote:

I have a 69 440 that is fairly stock. It has a few updates/upgrades including an electronic ignition, Hughes camshaft (basically an upgrade over stock HP camshaft), forged pistons (flat tops) and Mopar dual plane intake. It runs stock exhaust and carb. I had it out for the first time in a couple years last night. I put fresh fuel in it (pump gas - 91 octane) and I added a container of octain booster. Still, it detonates when I accelerate. I have not checked the timing on it yet (I know, I need to do this) but I would think if I had it advanced too far that it would crank over hard - which it does not. Any suggestions would be appreciated.

Thanks,

440 4 me

Octane booster does nothing! You need to check timing first.

Posted By: viperblue72

Re: 69 440 detonation issues - 06/25/12 02:21 AM

I agree with 440dart. Also the mp distributors they sell have way way too much advance in them if that is what you have. You will need to get it recurved if so.

Posted By: JohnRR

Re: 69 440 detonation issues - 06/25/12 02:29 AM

Quote:

I agree with 440dart. Also the mp distributors they sell have way way too much advance in them if that is what you have. You will need to get it recurved if so.

Exactly , if it is the old MP distributor it will have close to 30 degrees of mechanical advance in it , you need to get a timing light on it , also disconnect the vac advance if you have it connected till you get it all sorted out .