Do you need to worry about emissions? If your going to be tested you should get the EGR. If your state doesn't care, then I would go with the non-EGR.

You may also want to think about watching ebay for an edelbrock. Sometimes you can find decent ones for a pretty good price.

I installed a non-EGR Edelbrock Performer on my '78 L82. My car was missing the AIR pump when I bought the car so that wasn't an issue. I also took off the EFE actuator and the vacuum switch that threads into the thermostat housing. I replaced the thermostat housing with an aftermarket one. I also had my Q-Jet professionally rebuilt. Doing all this cleaned up the appearance under the hood quite a bit and eliminated any number of potential vacuum leak sources. The car ran much better afterwards.

One option is Edelbrock also makes an intake specifically for use with the Quadrajet. It's called the Performer RPM Q-Jet and they give it better performance numbers than the standard Performer, but I'm sure it's more expensive. I wasn't aware of it when I bought mine, but I'm quite happy with the standard Performer.

As far as aftermarket intake manifolds go, the Edelbrock Performer is likely the least expensive quality unit on the market that I've seen. As gmurray said, you can do better on a used one on Ebay, but a new Performer is about $115-$120 new, so unless you get a real bargain on Ebay, I'd stick with a new one.

I'd be interested in how close a performer RPM fits under a stock hood.  An easy way to find an intake leak is to take a hand held propane torch, turn on the valve, but don't light it, and move it around the running engine's intake areas... when you get up to a leak the motor will run up because it is sucking in the propane instead of air.  Why pull an intake when it can be a hose or carb plate leak.

Edelbrock says their Performer RPM won't fit under a stock Corvette hood. Maybe a drop base air cleaner may allow it, but I don't know. A lower profile carburetor than the stock Q-Jet may make a difference as well.

You definitely have a point...find the source of the vacuum leak before replacing parts.   

I put this one on my car. Kept the Q-jet. Used a GM drop bace air cleaner and it fit under the stock small block hood with no problems. Looks great, woun't break the bank and a nice preformance gain. Check it out.

 

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem& ;category=36474&item=7981232477&rd=1

  I have the Weiand 8004 manifold. Fits fine with stock air cleaner. Also you can run the Q-jet or a square bore carb................Relatively inexpensive too...................

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