carb recommendations?

[jeepboy45]

Hey guys...

Havent been on in a while. Life has gotten in the way lately. Job changes, etc...

Have a question about carbs though. Last summer I rebuilt a 360 and it runs beautifully... only 900 miles on it. Running a fairly mild Melling cam with 448 / 472 lift and 204 /214 degress @.050........Also using an old school Offenhauser 4 barrel dual port 360 degree intake. The carb is an edelbrock (basically a Carter) 4barrel 600 cfm... It needs to be rebuilt. Engine takes about 30 seconds of continuous cranking to get fuel from tank because it bleeds down when not run in a day or more. It runs horribly rich and currently cannot be leaned any more than it is.

Before I put $$ into it, I have been thinking about changing carbs, and considering a 2 barrel carb.

I've been reading that a 2 barrel is good for low end torque.... And it would possibly be better on gas mileage.

There is a basic formula ( CFM= CID x RPM x VE / 3456) for determining a good CFM match when plugging in the numbers for engine size, max rpm and volumetric efficiency. After checking that formula, I only need about 400 cfm. From what I've learned, most people over-carb their engines. If I am not mistaken, if I used a 2 barrel, at WOT the cfm would be where I need it, but at lower rpm, I wouldnt be wasting as much fuel... Is this correct.????

BTW, I am NOT changing the intake back to a 2 barrel intake.

Any recommendations?

thanks in advance,
brian

 

[Jimbos76cj]

How about a old school quadra jet? I am by no means a carb expert so that is just a random unfounded thought based on the fact that the secondaries would only open under a certain amount of vacuum allowing it to tool around actiong like a 2 barrel until you jump on the skinny pedal and then the bigger secondaries open up. Hopefully theres other carbs that work in the same manner that some one else can help with. Good to see you back and that block worked for you.

 

[cj7inthetwigs]

X 2 with jimbo, daddy always ran quadrajets.nothing like hearing the 4 barrel come alive.

Sent from my DROID RAZR HD using Tapatalk 2

 

[jeepboy45]

Thanks for the imput on carbs, guys...

For some reason the site isnt sending me an email letting me know there were responses. I had no idea until I was looking at my own posts...

It looks like I am going to try TB injection and see how that works out..

thanks again
Brian

 

[Flex BT]

To piggy back on this post, how can you solve the problem with the gas going back into the tank? Mine isn't as bad as this poster but it definitely takes more cranks the longer it has been sitting. I have a new fuel sending unit, fuel pump, and it seems like my connections are all tight.

 

[harleydragon]

To piggy back on this post, how can you solve the problem with the gas going back into the tank? Mine isn't as bad as this poster but it definitely takes more cranks the longer it has been sitting. I have a new fuel sending unit, fuel pump, and it seems like my connections are all tight.

I swap over to an electric fuel pump

 

[chris989604]

To piggy back on this post, how can you solve the problem with the gas going back into the tank? Mine isn't as bad as this poster but it definitely takes more cranks the longer it has been sitting. I have a new fuel sending unit, fuel pump, and it seems like my connections are all tight.

Mot likely the gas is not going back into the tank but evaporating or possibly leaking out into you intake. This is emptying the bowl and that is why you are having to crank the mechanical pump over to refill.

 

[harleydragon]

Mot likely the gas is not going back into the tank but evaporating or possibly leaking out into you intake. This is emptying the bowl and that is why you are having to crank the mechanical pump over to refill.

correct..the gas in the line might could get sucked back but there is no way it could suck the gas out of the bowl