I want an intake that will flow good in upper rpms. I dont have to pass emissions, but would use egr if it is needed to make everthing run right with the computer controlled carb but if not dont really care about it. I am not planning on getting the intake right away, but am looking at getting a set of heads, and I would like to know what kind of intake I am going to get so I know whether to worry about egr and crap.

Ben

 

As far as the computer itself is concerned, it only cares that there is something to receive its EGR commands - i.e., the solenoid. So, if all you did was mount the solenoid and run the wires to it, the computer would not set a code.

The spark advance curve may be a different story, as the EGR function tends to make the engine want a little more advance. Since that is built into the PROM, not having the EGR valve may make the computer give it a little more advance than the engine wants. That wouldn't be a problem at WOT, more like partial throttle in street driving situations.

As an example, my original LG4 manifold EGR passages were plugged. When I advanced the base timing to 6 degrees, it would ping, requiring mid-grade gas to make it stop. I put the GMPP manifold on before the rest of the mods, and with its nice clean passages, the pinging was greatly reduced. However, now with the polished chambers of the World heads, I'm running 10 degrees base and running regular grade gas - in almost 5k miles, I have yet to hear a ping. The only thing I haven't tried is plugging the EGR valve vacuum line to see what happens.

You could probably run a non-EGR manifold and get away with it with the right combination of other parts, and tuning.

 

Well I am looking at running aluminum heads so that will keep the heat and pinging down some I would assume.

Any suggestions as far as a non egr manifold?

Ben

 

Without an adapter, you're pretty much limited to q-jet bolt pattern styles - Performer, Action +, GMPP (which does have EGR). I think Edelbrock once made a q-jet RPM, but I'm not completely sure about that.

If you're willing to use a spreadbore to squarebore adapter, the sky's the limit. Stealth has a nice ring to it.

 

Do you loose performance with the adaptors? I was thinking maybe the stealth. Would it clear the hood with the adapter carb on it?

Ben

 

Im not sure if i remember properly but you can use and old holley street dominator intake. its a single plane, i used it once, and there was VERY little loss of torque. It seemed as if the mounting pattern could take both square and spreadbore carbs. you can get one on ebay for like 50 bucks.

 

I have that Holley intake you speak of. It is a single plane, divided plenum, w/EGR and it takes a spreadbore carb. My carb must be bogging, my low end doesnt seem all that great. Of course my tranny doesnt like to downshift, so I rarely see over 3000 rpm on the street. I think Im gonna play with my carb and try that out.

 

I dont think the intake had a divided plenum or egr. It was a very very short single plane. Thats why it kept some resemblance to torque on the street, and at high rpm is was great. Those old intakes are great, check out that carb there thats probably where your bogging lies.

Take care man, good luck