i have a 4bbl. Was wondering what the diffrence is.

The truck came with it. So im just wondering.

I found in some palces, the 2bbl gives a but more low end power, the 4bbl more mid/high end, also ones more capable of s/c and nos?

 

I thought bbls is for carburators
the 2bbl has two butterfly valves that are large
the 4 bbl has four, two smaller than the others, but open at a higher RPM for upper-end horsepower
i'm not positive though
anybody care to correct me?

 

I didnt know that they had 4bbl TB's I know mine is only 2, but it's stock. you have alot done to your motor and maybe they changed it over to a 4bbl? I dunno. but ya, the bigger your TB is the less botom end you will have and the more top end you will have. it's almost like a teeter totter.

 

Yes i havea 4bbl M-1 on my truck with a 2bbl adapter for my TB, unless i Carbed it, My TB is stock right now, im upig it to a 52 when i get some cash.

I can use more high end power. My low end is already a monster. 1st and 2nd i can rip through no problem, its 3rd thats a killer 60-100 i think i might get a 100shot for 3rd when i do 1/4mile.

 

He's talking about the intake manifold, not the TB guys. The 2bbl is the most common. It's used for mild to moderate N/A 318/360 setups or for moderatesupercharged applications. With the supercharger it's kind of gray area, you could go both ways, but you will lose more low end torque with the 4bbl unless you're running quite a bit of boost. For most people the 2bbl is a good choice. For 408 applications or large amounts of boost the 4bbl is the way to go! They call them 2bbl and 4bbl because the intake is designed just like they used to for carbed apps. Now we all have TB's but they still name it the same because it's still designed the same. And I've only seen one dak with a 4bbl TB, but I believe it was home made, not something you can go buy.

So with you're setup, having the 4bbl is going to impact your low end quite a bit. But hey... at least if you do go with some big power adders, you'll be setup for it. You could also change gearing to compensate.

 

If you say you have plenty of low end and not enough top end, then you should grab a larger TB, and then some Mopar "R/T" heads at some point. That will help that top end quite a bit. If you switched to a 2bbl or a stock manifold you'd see how much low end you actuallylost though, you'd be surprised

 

Ya my next mod is a 52mm TB, Either fastman or holley not sure yet, and i do plan on making a 408 out of this 360 block sooner or later, and the r/t heads, along with a cam, and everything else. Only thing i dont have that i need is $ lol.. But i can save about 500 a month with my new job, so i will be getting this baby a mackover soon. I have TONS planned for it.

The plan this year is "hopefully" to get..

New TB
Full MSD Ignition
Underdrive Pulleys (actually about to buy the ones from this site)
Rebuilt Tranny
and hopefully a set of r/t heads..

all that by the end of the year. Thats my plan. And some little stuff here and there. Fix some blemishes on the outside, new imblems and fixe my rollpan and tailgate.

 

Read up on the R/T heads - Hughes seems to think that the HD Magnum iron heads are better out of the box.