Port mismatch

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Shamrock--WV2NC

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I have a 74 Dart with a 318 2 barrel carb. I'm wanting to get an intake to bolt on a 4 barrel carb. I can't figure out which intake would work. I'll see some that say 318-340-360 small block but then read on a post that the ports don't match. I'm not doing a whole lot of upgrades but I really want a 4 barrel. What intake would work for me?
 
An eddy performer will work, it has 318 sized ports. 318 heads have smaller ports then 340's and 360's. That's the difference. Just find an intake designed for 318 ports.
 
For general daily driving, I would not worry too much about the exact port match. And without a cam upgrade, you'll not make any real use of the 4 BBL anyway. If you end up with larger intake ports than head ports, then use the larger port gaskets.

If 'twer me. I'd buy the larger port intake in anticipation of eventually changing to larger port heads.....but that implies eventually making some substantial upgrades to the whole motor. I am not sure that is where you are going long term so my view may not apply.
 

For a daily driver and a reasonable budget the 2176 dual plane is a good intake.
I started with the 2176 and a Edlebrock 1406 (600cfm) on a stock 318 and later added headers and a dual exhaust.
Some time later I built a 5.9 Magnum with a cam and EQ heads drilled for LA intakes and am still running that 2176 and 1406.
The intake ports are about 1/4 inch smaller all the way around the opening than the heads intake ports are. (which if you are going to have a mismatch is the best way) as you don't want an intake with bigger ports than the heads have or it severely disrupts the flow.
Yes, it's holding the Magnum back from making all the HP it could but it runs flawlessly at around 350hp on my daily driver.
Later on if you want more out of a motor you can sell it to the next guy with a mild 318 looking for a good intake to start with.
 
It's just going to be a little cruiser for me and the wife. Maybe one day if I find myself scratching off a winning lottery ticket I'll do a major upgrade. But for now, it's just a little cruiser. I will take it to the local drag strip for some fun.
 
It's just going to be a little cruiser for me and the wife. Maybe one day if I find myself scratching off a winning lottery ticket I'll do a major upgrade. But for now, it's just a little cruiser. I will take it to the local drag strip for some fun.

I got a used 2176 in excellent condition and a like new 1406 Electric choke for right at 100 bucks with a bit of patience and craigslist. :D
The chrome air cleaner cost me an extra 10 bucks.

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Either port size will work just fine with ZERO ill effects. Chrysler put millions of 360 4 barrel intakes on 318s right from the factory and they worked fine with mismatched ports.
 
Either port size will work just fine with ZERO ill effects. Chrysler put millions of 360 4 barrel intakes on 318s right from the factory and they worked fine with mismatched ports.

Huh, I thought it was a bad thing to have smaller head ports than the intake had.
 
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