470 4 barrel conversion, one cylinder missing

[HorizonblueDK]

Ok, here is the final answer to the question: Can you install a 4 barrel carb and intake manifold(from another 3.7 engine) on a 470, without changing anything else and get more power and a smooth running engine?

NO YOU CAN'T, IT WILL NOT WORK !!

As mentioned earlier in the thread, my 470 didn't run well, after I installed the 4 barrel, even though it is rebuild. After going through the ignition system, I didn't find anything wrong, so I decided to change back to the original 2 barrel. And what do you know, it runs like a champ again.

To make it run with the 4 barrel, apparantly some internals must be changed also. But that is not going to happen in my case. I will be satisfied with 170 HP for now.

 

[nola mike]

Ok, here is the final answer to the question: Can you install a 4 barrel carb and intake manifold(from another 3.7 engine) on a 470, without changing anything else and get more power and a smooth running engine?

I'm not satisfied that that's the final answer. Seems that the earlier 4xx used different cams for the 2bbl/4bbl. Later models clearly all used the same cams, which were different from the early models. Interesting thread though. I can't recall another 2 -->4bbl conversion actually being done here, can anyone else?

 

[shiloh87]

The cam specs for the 3.7 are similar to the 488, the big problem with a four bbl is the engines ability to deal with that extra boost of fuel.
With out the engine being set up for it ie, cams lift and duration, valving etc it just wont work very well.
In the end the 3.7xl is 170hp, the old 485 was 190hp, not much gain, maybe 5mph, and more fuel if running with the secondaries open.

 

[HorizonblueDK]

I'm not satisfied that that's the final answer. Seems that the earlier 4xx used different cams for the 2bbl/4bbl. Later models clearly all used the same cams, which were different from the early models. Interesting thread though. I can't recall another 2 -->4bbl conversion actually being done here, can anyone else?

I have not done any investigation, but I would suspect that the jetting in both carbs (2 & 4 barrel) hasn't been the same, from start untill the end of the 3.7 engine life.

 

[Subdriver592]

Ok, here is the final answer to the question: Can you install a 4 barrel carb and intake manifold(from another 3.7 engine) on a 470, without changing anything else and get more power and a smooth running engine?

NO YOU CAN'T, IT WILL NOT WORK !!

As mentioned earlier in the thread, my 470 didn't run well, after I installed the 4 barrel, even though it is rebuild. After going through the ignition system, I didn't find anything wrong, so I decided to change back to the original 2 barrel. And what do you know, it runs like a champ again.

To make it run with the 4 barrel, apparantly some internals must be changed also. But that is not going to happen in my case. I will be satisfied with 170 HP for no

Ok, here is the final answer to the question: Can you install a 4 barrel carb and intake manifold(from another 3.7 engine) on a 470, without changing anything else and get more power and a smooth running engine?

NO YOU CAN'T, IT WILL NOT WORK !!

As mentioned earlier in the thread, my 470 didn't run well, after I installed the 4 barrel, even though it is rebuild. After going through the ignition system, I didn't find anything wrong, so I decided to change back to the original 2 barrel. And what do you know, it runs like a champ again.

To make it run with the 4 barrel, apparantly some internals must be changed also. But that is not going to happen in my case. I will be satisfied with 170 HP for now.

4 barrels simply feed fuel into the air as the engine is sucking the air during the intake stroke. The engine doesn't care what carb is on the engine and doesn't know what carb is on the engine. The carb simply has to be set up right for the engine. Everything comes into play here. Float bowl level setting, jets in primary and secondaries, choke settings, etc. It can be done right but its not a bolt on modification. Best way to get the results you want is with an emissions analyzer with engine running. Most people aren't going to go through with that much effort. But it can be done if done right.