does any one know were my calibration n tuning should be at with this edelbrock 650 cfm thunder series carb?

 

It depends on the application.

Your carburetor should be chosen and tuned to what you want to do with the motor.

Use a vacuum gauge to tune the carburetor's fuel mixture screws. Play with jet sizes to figure out which ones let your motor run best (typically you jet a carburetor based on altitude, not for the size of the motor). Adjust the float. Set your idle speed according to how it needs to be set, etc.

Play with it a bit and you'll get it right. There is no definite setting with carburetors. Just fiddle with it until it's right.

Most Edelbrocks just need a fuel mixture adjustment out of the box. If it needs more than that, let us know. There are a few guys on here that like the Edelbrocks and we have one guy on here that is a carburetor specialist.

 

When I adjusted mine I turned in the right screw a quarter turn at a time until the engine stumbled a bit and then turned it out a quarter turn counting the number of turns. Then turn the other side the same number. Take a vacuum gauge and make sure the needle is steady. If it shakes a bit that should be fine but if it wavers more than 2-3 mercury you may want to adjust the mixture screws out a bit.

 

If Edelbrock has an equivalent to the 1405 and 1406 Performers in the Thunder series we'll need to know which you went with. One of the guys on here bought a 1406, which is touted as jetted for economy, and his built 351W ran out of steam on the top end. He then bolted his buddy's 1405 on and it ran like a banshee. We've compared all of the components of the two carbs and have come to conclusion that it isn't jetting but either the size of the needle/seat combo or something to do with the secondary booster clusters, both of which are different between the two carbs.

So, assuming they have similar carbs in the Thunder series, my advice would be to go with the one that is set up for what you want the vehicle to do. There certainly is a difference.

 

Why does everyone seem to want Carter carburetors on Fords?

 

So they'll run correctly. Just look at my reposted spark plug pic's on Rusty and tell me the out-of-the-box Holley was jetted better than the out-of-the-box Carter.

Edit: Monster, Bill Vose is the guy that was referred to as a carb specialist. He is. He's forgotten more than I know about carbs. And, by the way, I'm one of those who likes Edelbrock/Carters, if you haven't figured that out.

 

Gary, an out of the box Holley O-1850-3 is jetted richer than the old R-1850 was. I used to have to jet them down for most uses. The old Carter performance carbs were jetted rich too.

 

Don't remember what list # it is, but the 4160 Holley I have is a universal fit, as is the E'brock. And the Holley is jetted the way Holley sells them, as is the 1406 E'brock. So, if you are buying off-the-self today there is a big difference between the two. As you saw, I was getting 12.25 MPG with the Holley, and now get 14.25 by just bolting on the E'brock.

However, I suspect that the WOT performance is better with the Holley, although as of now I haven't quantified that but will, but the part-throttle performance is better with the E'brock. It idles better, has better tip-in, and is crisper than with the Holley. On the other hand, the hot-start is better with the Holley.

I realize that both carbs are tunable, but I'm just comparing the out-of-the box setup. And, by the way Bill, I'm just having fun.

 

Did all this work ran great for two days, ran out back tank, hick up, n then changed tanks. When it got fuel it back fired twice, stayd idling, but absolutely no rpm response. When stoped, it died. N now it won't fire. Turns over? Don't here any bad sounds? Such as rods or valves?

 

Rejet springs n rods that is, as 'work' done. Tune in as well?

 

Have you checked your fuel filter. Sounds like after you switched tanks you dislodged some gunk and clogged the filter. Switch out the fuel filter(s) and give it a shot.

 

Monster - I can't figure out what you are saying. What does "tune in as well?" mean? When you say "absolutely no rpm response" what do you mean? Does it just stay idling? Does it bog?

Please take more time to explain so we don't have to guess what the symptoms are. I'll await a better explanation before responding.

 

Was trying to convay what happened when it just stoped working. That's how it broke down, as far as tuning in, reset idle n timing advance with the carb work. And a new cap rotor plugs and wires. Now it just won't start at all. Like I said previously, turns over, but nadda?Harsh b day morning,boooooo , this all happend yesterday.

 

Will check filters, going to tow today.

 

What is "n" timing advance? Next? New? Is there an "o" timing advance?