Merry Christmas guys.

I have a 428 in my truck. Most likely a Q series. I bought the truck back in June. The engine has a Carter AFB carb on it, not sure of the CFM. When I got it it seemed to idle high. I played a little with the carb adjustments without much change in the idle resulting. When I had her on the highway above 40 mph and then got into it, it would "ping" like crazy ( just a note: the ping existed before I played with the carb ). So I played around with the timing and retarded it by ear. This brought the idle down somewhat and the pinging went away on acceleration. I have also noticed that it tends to be a little more sluggish as a result. It seemed to be a bit more spunky with the timing advanced. Also, when it has been running for more than twenty minutes (est. ), when I turn off the ignition she sometimes diesels and sputters ( no back fires ) kind of like: chugga-chugga brt-brta-brta hissssssss ( best I can do in replicating the sound ).

One thing I couldn't see when I went looking is any timing marks?

In the spring I plan on putting a new Holley 650 - 700 CFM on her and getting a tachometer. I had a compression test done back in August and the compression is solid across all eight ( 155-165 ).

Aside from what I have stated she runs fine and she definitely has a drinking problem!

If anyone knows anything about this AFB carb (4V ) I'd appreciate any input. It only has two adjustment screws that I could find and no other points ( obvious ) for adjustment.

So, do you guys think I need to advance the timing somewhat or just run her like she is? I know one thing for certain, she is definetly running rich. My dual exhaust is black as coal at the tail pipes.

 

sounds like you need a little more timing and BETTER GAS. That 428 would probably like a 750 holley or demon carb better. It's going to be real thirsty no matter what carb is on it. Can't help you with the carter though.

Did you clean the balancer real good and not see any marks? If so, you can get it to number one and put some timing tape on it.

 

Ranger589, let me know about your decision on carb selection. I'm completely in the dark on selecting a carb for my 410 project. Have been looking at the road demon, holley avenger, and stock autolite 4100. Seems I get a different answer to cfm recommendations from every site. Everything from 570 cfm holley avenger to 625 road demon.

 

Hey tater, imo demon or holley is the best decision you could go with. If you're just looking for just a street carb, I'd go with about a 650cfm. If you want a little more performance I'd go with a 750. I'm assuming this is on a fairly stock build, not too wild. 600's a little too small imo.

 

It is basically stock, .030 over, with the Crane 901. Everything else is stock. I have a performer intake but by the sounds of things I'm just as good to run the stock intake. I'm a little worried about CR being a little high, I'm figuring around 10.5 but I don't mind buying premium fuel. Thanks for the reply, Tater

 

Sounds like you need to recurve the distributor. Not enough advance at idle and low RPMs makes it fell "sluggish", while too advance above 2000RPM and you'll get that pinging.

Either that, or the vacuum advance isn't adjusted right, or just plain not even working anymore, and someone played with the initial timing to get it "peppy" again and caused the pinging.

Time it at like 6 degrees BTDC at idle, and while watching the timing, bring the RPMs up to 3000 and see what it does. Try to write down what the advance is every 500RPMs or so, and report back with the numbers and the guys will definitely have more to go on.

Go over the damper, find the "0", and every 10 degrees BTDC another line, and use white paint with a thin brush to mark each line and maybe a number if you can get it on there. It should be very easy to see with the timing light after that

 

Here's a great website if you should decide to recurve your distributor yourself. I think it's pretty informative and complete. Duraspark_distributor_recurve_instructions_index

 

Thanks Krewat.

Not sure what equipment I need to do what you said in the third paragraph above. I only have a timing light. What do I need to read the advance? Is there a portable ( cheap ) tach I can get to hook up under the hood to get RPM readings as well?

Being a shade tree mech. I am used to basic stuff. I love to learn though. And I can say with all honesty that I do love working on my old girl. Can't say that about the new stuff!

 

Thanks Krewat.

Not sure what equipment I need to do what you said in the third paragraph above. I only have a timing light. What do I need to read the advance? Is there a portable ( cheap ) tach I can get to hook up under the hood to get RPM readings as well?

Being a shade tree mech. I am used to basic stuff. I love to learn though. And I can say with all honesty that I do love working on my old girl. Can't say that about the new stuff!

 

Ooops! I think I know what you mean now. Check the reading on the damper @ 500 rpm intervals and document? Still need advice on gauge for tach under hood. Thank you, Todd.

 

Older parts stores probably still stock a tach/dwell meter. Or you can borrow one from someone. Or, take a regular tach gauge, put alligator clips on the leads, and connect red to + at the battery, black to - at the battery, and the green goes to the (-) side of the coil. Just be careful you don't drop it or it's wires into the fan or the belts

 

Thank you sir! Still a little rusty doing stuff since I had my 65 F100. Perishable skills as they say.

I'll check out NAPA for the tach/dwell meter. Curious? Does a dwell meter work with electronic ignitions? No points = no dwell?

 

There's still a "dwell" with electronic igntions, you just can't change it

The "dwell" is the amount of time that the points are closed, energizing the coil.

The reason I said a tach/dwell meter is that you are probably going to be stuck buying something that does dwell as well (pun intended). Still shouldn't be a big-buck item though.

I have an idea, from Napa, you're going to get this:

Store Locator | NAPA Online