Ive got a 410 merc in my 74 f250. Its got a mild cam, forged pistons, and a carter 625 carb. Other than that it is pretty much stock. My problem is that it has always fallen on its face if i got on it really hard, just for a split sec and then ran out like a raped ape. Now all of the sudden when i take off mildly it will spuder like its missing for a couple secs and smooth out and run perfict. It sound like it has to do with the carb. Does anyone have any suggestions?

 

1850 Holley, 600 cfm. Buy 'em all day long at swap meets for $50, get the quick kit, go

 

I had a new edelbrock did sputter when when smashed on it from a stop, my understanding at the time was i needed to change stepup springs. Anyways the problem is common, and many others have said the same.

The carter is super easy to rebuild, i prefer holleys though..

 

Out of all the carburetors I've modified etc the only two I couldn't get the
stumble out of were two Carters and just so happens I've only messed with
two Carters. Battin' a thousand on those. :/

Always wondered if Edelbrock had Carter be sure that wasn't a problem with
the stuff with their name on it. The two Carters were a couple of the coolest
looking and well-made-looking carburetors on the inside too. :) They both
would go like nobody's business right after they got done fartin' around, just
like you described. I'd like to know what needs to be done besides getting a
Holley. :)

I richened up the low speed circuits and closed down the air correction holes
and raised the fuel level and all sorts of dangged stuff, even stuff that couldn't
be left like I change it to, just to see if it'd help. Nuthin' worked. :(

Alvin in AZ

 

Accelerator pump need tuning? (second time I've said that today)

 

Maybe its just me but im not getting much useful info here. I've already tried the things that were suggested. Ive been looking at getting a Holly sence I got the truck. Does anyone have anything good to say about the Holly Truck Advenger? I'm wondering if it performs just as well on the street as they say it does four wheeling. My engine is not built to the nuts but its go some ***** and i dont want to just throw a cheap carb on there. Thanks for all of the info. Its all appreciated.

 

The 1850- 600cfm isn't a "cheap" carb quality-wise, but is quite affordable, as there's always a few at swap meets, run very well with little maintenance, are very tunable, and have the side-hung floats you want for off-road. You can pick up a decent one, clean it up with the quick kit, and be on the road for less than $100. Parts almost anywhere, and rarely need more than cleaning, gaskets, needle and seat, and adjust the pump. Very adequate size-wise to feed your mild 410, and get decent mileage. You can spend a lot more, but not necessarily get more

 

I think i have decided that i am going to try and find a Holly 750 CFM. All of the people that ive talked to have had good luck with those on there FE engines. What do you think?

 

I think a 750 is going to be too big. It's too big for a 390. And if you do use it, it will take a lot of tuning "out of the box" to get it right.

 

A 600 will feed a mild 410 just fine, a 750 will be more than you need- especially in a 4x4. And the 1850 600 has the correct side-hung float bowls for a 4x4, and a 3310 will have front and rear hung cathedral bowls, and if you do any serious hillclimbing, will flood & starve on you. Bigger isn't always better- a 600 will have great throttle response on that 410- night and day from what you have now