Does a original 75 dart swinger with a 318 have EGR?

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Stucker152

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Just purchased a all original 75 dart swinger with a 318 and auto Trans. Looking to upgrade the cam, lifters, carb, and intake to the edelbrock performer series. But I'm unsure if my 318 has egr or is without it? Someone please help I'm new to classic restoration but willing to learn. Thanks
 
Yes, your '75 would originally have come equipped with EGR. Depending on the vehicle's equipment and build specification, it might also have come with an OSAC valve (described here) and/or a catalytic converter. You will probably be happier without EGR, and it is unlikely you (in Great Falls) will ever face emission tests picky enough to flunk you for not having it on a '75 car. For a quick brushup on the various emission control devices and systems you may find on your '75, see here.

Because you are new to the hobby, as quickly as you can, get and read the three books described in this thread (which mentions slant-6 engines, but the books apply regardless of what kind of engine you have).
 
Worse yet, on the first couple of years, you CANNOT tell by just looking at the external engine. The first couple of years, Ma simply drilled "leaking orifices" in the floor of the intake, right into the exhaust crossover. Only way to tell on those early cars (72, 73?) was to remove the carb or open the throttles and look inside the manifold plenum

http://www.forabodiesonly.com/mopar/showthread.php?t=169776

29w4wtz.jpg
 
One year only for that POS Floor jet system with no valve. It was '72 only, California only. All '73-up EGR systems had a readily visible EGR valve.
 
You'll never know if the jet is working or not. Even if it was recently cleaned out and working properly, you would never ever know the performance difference. Idle or cruise difference either.

the EGR valve is only open when there is vacuum. So this means that at wide open throttle (WOT) the valve closes. The jets in the floor show no appreciable difference in performance (Low performance) when removed. If anything, removing the equipment will have the engine run worse since the carb is so set up and jetted for the smog equipment to be there.

The OSAC valve should be thrown as far away as possible, into a garbage can headed for China if possible.

The cat, if needed, should be replaced with a high flow unit, again, if needed. If it is not needed, you can live without one and the engine will run fine.

If your looking to upgrade the engine with dual exhaust, twin cats can be use without issue or any performance loss worth mentioning or noticing it missing.

Been there, done that, to many times to want to remember talking about. I have made this MOD to my vehicle and friends vehicle which all passed emissions tests.
 
Also, stay away from the Edelbrock cam. Look for something better in the RPM range your driving in. Headers are a excellent upgrade, not a "Need to do" thing. Dual exhaust is a great idea and I highly recommend it.
Use a MSD or equal box to get the best mileage out of the car. Tune that carb well.
 
slantsixdan said:
One year only for that POS Floor jet system with no valve. It was '72 only, California only. All '73-up EGR systems had a readily visible EGR valve.
Click to expand...

While this may actually be technically correct, "it may not be." That's because even in the 70's you just might find an engine that had been rebuilt/ swapped, and find a different engine or intake in a given vehicle. Now that these cars are 40 and more years old, moreso.

Hell my own 70 sixpack RR got a 71 340 dropped into it in about 72-3, and I got a LOT of what is THIS?
 
slantsixdan said:
One year only for that POS Floor jet system with no valve. It was '72 only, California only. All '73-up EGR systems had a readily visible EGR valve.
Click to expand...
The '73 340 and 400 4bbl engines didn't.......they still had the floor jets.
 
Interesting -- I learn something new every day! Factory manuals disagree at least in part; there is an EGR valve called out for 400-4bbl applications (p/n 3671 420, not used on any other application). None called out for the 340, though there are two for the 360 (California vs. 49-state), one for the 318, and one for the 440. There are some additional valves listed as "8 cyl" without a displacement spec; I'll dig out my '73 emissions manual (w/details on each configuration spec) and see what it's got to say.
 
Cool well I'm gonna take out the egr system when i switch manifolds. Now I'm in the process of swapping stock headers for a set of block hungers by patriot and dual exhaust. Just can't figure out what muffler I wanna run. I was thinking thrush turbos or a flowmaster? I don't wanna get too pricey like borla or anything about 75 bucks a muffler. Just something with a real loud and deep sound. The louder the better in my opinion.
 
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