Doing a search for "Arns85GT carb" or "Oreif carb" will get you a large amount of threads on carbing a V-6 as well as how to optimize (hot rod) a carb'd V-6 for more power.
To answer your questions:
Offenhauser use to make an intake. Occassionally these show up on Ebay or the S-10 truck forums. The Edelbrock is still made and sold thru places like Jegs and Summitt Racing.
You can have a wedge made, But in reality it really doesn't matter as it has minimal effect on how the engine runs.
The carb to use is either the Holley 500 cfm 2bbl or the Holley 390 cfm 4-bbl. There is a 350 cfm 2bbl as well, But the 500 cfm 2-bbl works a little better.
Yes, It eliminates all engine ECM sensors. It is best to leave the ECM in the car (just remove the check engine light bulb out of the dash) because it controls the fuel pump safety feature. (If in an accident it will shut off the fuel pump) . Side note, You will need to either use a feedback style regulator or use the 4-cyl Fiero fuel pump and a regular regulator for the fuel pressure. Carb's need 4psi to 8psi. The V-6 fuel pump is around 45psi and the 4-cyl version is only 12 psi.
For the ignition you need a distributor from and 85 or earlier S-10 pick-up truck with the 2.8L V-6. These have the vacuum/mechanical advance.
The Holley 390 cfm 4-bbl with electronic choke is the recommended 4-bbl carb for use on a 2.8L/3.1L/3.4L with the Edelbrock intake.
Generally, a carb'd engine will NOT pass emission testing at the mid-80's standards. If you want to make it pass, You will need to go with the 2-bbl as the 2-bbl intake riser allows for an EGR but the 4-bbl does not. The exhaust has to have a catalytic converter. You will also need to lean out the carb and retard the timing a little prior to testing. It might just pass, But I don't know anyone who has tried, let alone passed, with a carb'd engine.
Check your local and state EPA laws. Some states allow you to classify the car as a "Classic" and you can get an exemption from emission testing for the car.
The pro's and con's are the same as any carb vs. EFI engines. There are many heated debates on those points both on here and other forums.
In the end, It all comes down to what you want. (personal preference). If you are an "old school" hot rodder like myself, You will find that the little V-6 can be a fun engine to play with. There are some decent performance parts like cams and headers for them as well as a roots style supercharger for use with either a carb or TBI injection. The 3.4L I built had the heads ported, polished, and shaved, a large cam, roller tipper rockers, the 390 cfm 4-bbl carb on the Edelbrock intake and it peaked at around 230hp at the crank. On a 2.8L if the same work is done it will be around 210hp.
Personally I prefer a carb'd engine in my Fiero. I had an "old school" hot rodded 3.4L with a carb then later swapped to a V-8 with a carb. In 5 years of running a carb'd engine in my Fiero I have never had any issues with it and enjoy driving it often.
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Happiness isn't around the corner...
Happiness IS the corner.ZZ4 Powered !![This message has been edited by Oreif (edited 12-04-2008).]
