4 bbl carburetor

[antihero]

wondering if any one new what brand 4 bbl carb would fit on the 2.8l i was told it could be done but i not sure which one and what intake manifold i would need

[JeepcoMJ]

wondering if any one new what brand 4 bbl carb would fit on the 2.8l i was told it could be done but i not sure which one and what intake manifold i would need

 

you need a holley 390cfm 4bbl carb, with a edelbrock 4bbl intake

 

 

http://www.edelbrock.com/automotive_new ... perf.shtml

 

that should show you the intake...4th from top i believe, maybe 5th.

[hemi_comanche]

you need a holley 390cfm 4bbl carb, with a edelbrock 4bbl intake

 

 

http://www.edelbrock.com/automotive_new ... perf.shtml

 

that should show you the intake...4th from top i believe, maybe 5th.

 

Yep, that's the one. I really don't recomend the 4-barrel on the 2.8l. Your best bet is to save the money and put a good 2-barrel on the stock intake. You will enjoy the driveability much more. I recomend something like a Weber 32/36 or 38. I have been down the 4-barrel road with the Holley 390 on my 3.4l with the Edelbrock intake. I had full exhaust, MSD, and some small jets and it was too much. You really need to have a cam to justify moving to a 4-barrel when you can get a nice 2-barrel that will do the job just as well, and probably net better gas mileage.

 

This is of course just my opinion and me digging from my personal experience on the matter.

[Eagle]

All things being properly set up, it is impossible for a 2-barrel to generate as good fuel economy as a 4-barrel.

 

A carburetor relies on air velocity over the venturis to suck gasoline out of the fuel bowl and into the air stream. Faster air velocity results in more uniform fuel flow as well as better atomization. In order for a 2-barrel carb to run an engine at all speeds, it has to have the bores sized to allow sufficient air flow at the maximum anticipated engine RPM. At any {engine) speed below that, the air velocity through the bores slows down. The throttle plates are what regulate this, and try to keep the velocity up, but any time you push down on the peddle and the throttle plates open, the air velocity drops. That's why carbs have accelerator pumps -- to temporarily pump extra gas into the air column when the air velocity is too slow to suck enough through the venturis.

 

The whole point of a 4-barrel is that the primaries are small -- much too small for full throttle operation, but optimally sized for light throttle cruise. The air velocity through the bores is faster, so the atomization of the fuel as it comes out of the venturis is better. When you need more power and/or higher RPM than the primaries can give you, the secondaries (which are usually significantly larger than the primaries) open up and make up the difference.

 

If you set up and drive a 4-barrel so that most normal driving doesn't open the secondaries, there's no way a 2-barrel can touch the 4-barrel for economy. The problem is that most people set up their 4-barrels to get into the secondaries almost all the time, and they drive with a heavy foot, so they're just sucking gas when it isn't needed.

 

The new Edelbrock 4-barrels are copied from the old Carter AFB line, and I loved those carbs. Easy to tune by swapping jets and metering rods, and very reliable. Secondaries were mechanically operated, not vacuum operated, so that was one less thing to go wrong.