I rebuilt my 351m a year ago, never have gotten it running tip top, don't run it much. In disgust, I replaced the Holley 4160, just couldn't tune it, but end up with a totally different issue. The Holley was flooding, caused gas in the oil, ran so rich you couldn't stand next to it. The Carter AFB was used, no I didn't rebuild it, just directly installed it, it fires up without issues at times, electric choke is far better than the manual it replaced, but it has issues running down the road. I drove it today, feels real sluggish and atarted popping out the exhaust when i'd get into it. The metering rods are #16-241, could it be too small causing a lean issue? I put an RV cam in this thing and I'm getting pissed since I haven't been able to tell any difference than before the rebuild.
I don't believe that I need to upgrade from the origional Dura-spark, my problem has to be something simple, like tuning, but turning the distributor isn't improving it, must be else where. I put the large port on the front of the carb to the PCV, the small one next to it is on the distributor vacuum advance, I bought caps to plug up everything else, the brake booster and transmission modulator are on the intake port.
After rebuilding, I found the machine shop that done the heads had swapped intake/exhaust spring on a cylinder, caused me to bend a push rod, the intake spring combined with rotator on the valve caused it to run out of room for lift. When the head was pulled to correct it, I decided to go ahead and pull both, replace all spings with new, should have decided it when I did them first.

 

Are you sure that you have no vacuum leaks?
What is your vacuum at idle?
What color are your plugs?

Is it a 600 CFM Carter?
If it is go to the Edelbrock website and download the tuning procedure for a #1406, then determine which edelbrock metering rods the Carter 16-241 rods are the equivalent. Then follow the edelbrock procedure for tuning the carb.

 

I saw on a list once that my rods are the smallest made for those carburators, it's a 600 CFM from a 351 Windsor I believe.
I need to get a vacuum gauge, don't see where I'd have a leak, intake is tight and all ports are capped with new caps.
The plugs could be foulded out, thanks to the Holley, I'm going to get some new ones, guess I need to go ahead and get them, they were new when the engine was first fired, after my rebuild.
Wife has to do all the work under the hood, sits far too high to reach from my wheelchair, I do the over hauling of parts once she gets them off, I try to keep things simple for her.
I would think it should near peel the rubber from the tires once it's right, before rebuilding it, it almost spun the heavier TSL 35x15.50 tires, the MTR 35x12.50 should be easier.

 

How does it idle?

 

Seems high, in gear the truck shakes, almost vibrates, holding it at red lights is odd, affraid if I turned the idling back, it won't stay running in gear.

 

I have an issue with my brakes too, I'm affraid one is sticking, almost impossible to back up, after trying it in 4 lo I'm positive there is a brake problem, just not sure how bad it is in drive, it's just obvious backing up.
I'm hoping to get at the brakes first, before throwing anymore cash under the hood, I just want to know where to put it. The plugs were new, but knowing the oil was so drown in fuel, I'm sure they are fouled out. I've replaced almost everything under the hood on that engine, the distributor remains origional, I cleaned it but, but and starting to question the pickup in it now, ign box is new and I have an MSD Blaster II coil.

 

Was there any material milled off the heads?

You may need to shim the rockers. It is possible that your valves are not closing fully.

 

That can't be it, wasn't running this way after the rebuild, was flooding, but no popping and stumbling. When I drove it before the rebuild on the Holley, it ran incredibly well, the 4 barrel wasn't operating, so there was no throw back power, but ran and drove great, then after rebuilding, I couldn't get it set back up right.
Just wondering, I had her reuse the 1/4 cardboard spacer, could it be leaking, causing this, I have the one with 4 holes, it was on with the Holley.
I'll get the plugs changed and the gasket, then see if it clears up, and go from there.