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I got a smoking deal on a whole 360 for $75. I was really after the drive accessories and brackets for my Jeep build. However this has a stock 4 barrel intake on it. I planned on buying an Edlebrock intake for mine, but I'm thinking about using the stock one off this engine.

What are y'alls opinions on using a stock 4 barrel vs an aftermarket?

Is it a spread bore or square bore factory 4bbl intake? If spread bore, you will need an adapter to fit an Edelbrock. Not worth it IMO. Plus the factory intakes don't flow as well and are heavy. Better off with an aftermarket.

The aftermarket manifold is aluminum and much lighter than the factory iron manifolds. The aftermarket manifold is also more optimal for performance, but I would guess the factory manifolds are marginally better for the usual low-speed, part-throttle use that Jeeps see most of the time.

There are two 4V manifolds. The early one has a standard Holley square pattern. That will work with all your aftermarket carburetors. The later one ('75 on?) is for the Motorcraft 4350 carburetor, and is an oddball. The 4350 has a unique spread bore pattern and is the only carburetor that will fit this manifold without an adapter. The adapter is not cheap (ca $50-75?), if you can find it. You could use the 4350 carb, which works well if the carb top has not been warped by over-tightening the air cleaner bolt (pretty common).

If it's the early square-pattern manifold and you don't use it, someone will want it. The 4350 manifold is a boat anchor.

(Click submit once. Go back if nothing happens, and your post will be there).

The stock cast iron 4v intake is a slight upgrade over a stock 2v, but is still really not a very good intake. The edelbrock performer is a night and day difference. And I have run both on the same vehicle.

I tend to disagree about the cast iron 4bbl intake being marginally better than a 2bbl setup but that is me. Spread bore intake is pretty much a wheel chock. That said, we have a 401 with one that has the Transdapt 2199 adapter to fit the Truck Avenger. It's a damn site better than a 2bbl.

Thanks for the responses! But crap! I think it's a spread bore. I'll check it again tonight.

Nothing wrong with the spread bore vs the square bore. You just need the adapter that Flint mentions above (Transdapt 2199).

As for the 2v vs 4v, the v4 really doesn't flow much over the 2v. The difference is that the stock 2v carb couldn't saturate the 2v intake. But a 4v carb can saturate the 4v intake. So you pick up an easy 20hp over the 2v (I think thats what AMC rated the difference as). Meaning if you took the 2v intake, and the 4v intake, and used the same 2v carb, there would be virtually no difference.

But with the performer intake, you open up a lot more performance in both throttle response and power. Plus it will let a bigger cam work if you ever go that route. AMC heads are already quite good, so they aren't much of a bottleneck for mild-mid level builds.

I get you Brandon. I have both flavors of cast iron 4bbl intakes laying in my shop. Not really interested in installing them on anything here. I should drag them outside to one of the scrap heaps.

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I ran a Truck Avenger on a square bore 4v intake on my first wag, back 10 years ago or so. It was a 670cfm TA and I had to dial it way back because it didn't flow all that well. It was certainly too much carburetor for that manifold with a stock cam. I could have gotten away with a 470cfm and not pushed the limits of the carburetor.

Sometimes, even if it's free, it's not worth it.

Mine is the spread bore type. No big deal, I planned on getting an Edlebrock anyway to support the other HP mods I plan on doing.

fulsizjeep wrote:I get you Brandon. I have both flavors of cast iron 4bbl intakes laying in my shop. Not really interested in installing them on anything here. I should drag them outside to one of the scrap heaps.

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Do you have a Holley pattern non EGR intake?