4bbl vs 2bbl intake for tbi

Hi guy, been a year that i made my Tbi conversion on my amc 360. Been running well since them.

I'Ve been offered a edelbrock 4bbl intake to replace my stock 2bbl one.

Tbi unit is from a 1989 chevy van, so it's a 2bbl.

My question is, does it worth swapping the 4bbl intake in place of the 2bbl and using an adapter for my tbi?

Will i gain some power or i will throw my money by the windows?

Thanks for advice.

 

I would pass. The 4V configuration is specifically made for the carburetor secondaries that remain closed for most driving. This strategy insures that the small primaries make a lot of vacuum at low speed and cruise. High vacuum means precise fuel control, for a carburetor that is essentially powered by vacuum. With fuel injection, manifold vacuum is only a control signal, so it only needs to be large enough that it can be reliably measured. So a throttle body already has very low restriction, compared to a carburetor. No need for secondaries.

The 4V manifold is made to flow well when topped with a 4V carburetor. I would guess that the pathways are optimized to flow well for both the primaries and secondaries. So do you position the throttle body at the primaries location, at the secondaries location, or somewhere between? I suspect a lot depends on how the TB is positioned on the 4V manifold. My guess - you will not feel much seat-of-the-pants difference between the two manifolds.

 

Depends on the manifold. If its an open plenum you could loose low end.
The reason you might think about it is that I suspect the bores on your throttle body are larger then the bores on your manifold.
If the manifold accepts a spread bore type carb there are adapters that place the throttle body over the larger bores for less restriction.

 

If the adapter or intake you are using is restricting flow as many do you could be losing performance. Many TBI units have very large throttle plates and restricting them down can be the same as running too small of a carburetor.

 

If it's the common Edelbrock Performer intake, it's a split plenum design....no split between the primary and secondary bores, just between the two halves of the intake.
I don't have experience with the AMC V8 specifically, but I have done several swaps of a factory intake for an Edelbrock intake and noticed an improvement in power and throttle response...plus it's a whole bunch lighter!
If the price is right I would not hesitate.

 

I am running an Edlbrock on my 304.. It is much lighter than the cast iron stocker. Mine is the 4bbl one. You will need an adapter to unstall the TBI body to the manifold I know of a few places that sell them.

I am more than happy with my TBI. Will it give gains in performance? I can't answer that as I installed the Edlbrock during my TBI conversion.. I will say that throttle response and performance are far better than any carb I had on there, and I had 3, including a Holley..

 

Thread revival and hijack...hope you don't mind Johneyboy.

So...if starting from scratch and going to a TBI from 2V carb, does it make sense to go with the Edelbrock Performer intake, then choose the right TBI to go with it?

Thinking Affordable Fuel Injection.

 

I'm running a Howell and Edelbrock performer manifold..
can't say anything but good things.

 

I used Affordable.. Cust service leaves a bit to be desired, but it is affordable.. Knowing what I know now I would go with Hamilton TBI.. Cost more but he won't leave ya hangin like Affordable did me.. I made up my mind that since I was going TBI, might as well upgrade he manifold..

 

Sounds like I'm heading down the right road then with the new manifold. Was thinking new Holley carb too, but by then I'm ~$800 into it and for a few hundred dollars more I can have TBI...so now to choose a good TBI supplier.

 

I'M running the Affordable fuel injection system on my 360. Those guy just stripp down complete tbi system from 89-94 305-350 gm. IT's all oem part so if you need part it's pretty easy to get them trought auto part.

They prepare all the wiring, taking all uneccesary stuff.

 

I had a Holley on my 304.. It was great in town.. Offroad it sucked.. I bought a MC 2100 and life was good. Then switched to TBI a few years later. And the Holley? Gave it away

 

I had the mc2100 before going tbi, i don't have much complaint on the mc2100, works well on and off-road. The reason why i went Tbi was the cold start, we have often -22 f during winter so carb was having a hard time to start the engine. With tbi i just turn the key and it start right away.

 

MC2100 here too. I'm tired of "dry bowl" syndrome and the occasional out of tune issues. Spent a few hours last weekend tracking down a stuck choke that was flooding the engine. The carb is great when it's working, never had a problem, even at extreme angles, I guess I'm just getting too old and cranky to deal with it when it gets out of tune.