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Carburated Motor in a 84

Dec 27, 2001
Matthews, NC USA
1984 Coupe
One of the previous owners of my 84 Coupe replaced the original motor with an carburated 350.

Most of the emissions plumming looks intact, but there are many wiring harness plugs unused.

I'm a little concerned about passing emission tests here in North Carolina.

I would like to replace the carburated intake with either a stock fuel injection system or aftermarket unit, but have no idea if the heads would have to be changed.

I'm looking for advice on the best course of action.



I'll bet it's Manifolds up that got changed ( which will be expensive enough to trade back) this will be a BIG project to get EVERYTHING back to stock.

You will have to find all the X ram pieces
( Sport Imports 1-818-765-3333 ) I know for a fact
he has 4 or 5 84 cars/engines.

The other thing is ANY of the wiring harnesses are cut that will add to the pain.

Do you want to go HI-PO X ram.. thats going to be a new cam, intake, heads, ECM etc for somewhere in the 5k area when all is said & done.

I'll bet you have cast iron heads & stock exhaust which would indicate it was manifold up conversion.

Got pictures?

Food for thought.

carburated 84


I just took some pictures, and will probably send them via email.

Not quite sure how to display them here otherwise.

My thought was to use something like Edlebrock's Performer TPI for the small block. This one is suppose to be a direct replacement for the carburated intake. Negative side of that is that it's $2k.

I realize that any replacement is will be expensive, but my primary goal is to make the car a daily driver and legal. If I can squeak by with a Carburator for inspection short term, I'll worry about the replacement later.

The harnesses do have a few splices here and there, but not a real hack job as I first feared.

Thanks for the help,

Oh By the way

You might want to check with the Smog people in your area about if what's under the hood can be altered.. or it has to 1000% factory to pass your visual inspection, IN CALIF it must be STOCK or BZZZZZZZZT you fail, and have to go down this horrible appeal process , reguardless that you actual emissions are lower than called for..
Send the pictures to my home


Just FYI

Got the Pic's

It's very hard to tell from these... but it looks like a different engine was dropped in TOTALLY.

It looks like the timing cover is orange, you need to look down under the heads if the block is orange too!

From there...it's a crap shoot...

Need more digging to be certian

Engine swap

If you really want to know what you got find the casting numbers on the heads and hopefully a serial number on the block which is located on a pad on the right front of the engine. With these numbers you can start to find out what you got. There are web sites for matching casting numbers with year model and etc. of engine.

I have an 84 and also live in NC. I don't think the engine has to be original, as long as it passes a tailpipe test you should be ok.

If you are sure the catalytic converter is good, I would take it the the inspection station and see if it will pass. You might get it to pass just the way it is.

Of course I'm assuming that your car has the catalytic converter still in place. During engine upgrades and or swaps, people like to remove these to open the exhaust system a little. The other thing they may have done, is that they may have removed the converter and busted the catalyst out. If you are not sure, I would check it to be sure before you go through an inspection

FYI, if the car is tuned well and you use only high octane fuel, it is possible to pass a tailpipe test with the catalyst removed from the converter.

Mike in Raleigh
caburated 84

You brought up a good point about the cat. conv..

The vette failed emissions this saturday. With very high HC and CO numbers.

Does anyone know if the cat. conv. contributes that much to the emissions numbers?

Sounds like a good tune up and some RXP would do the trick.

Are you a GROSS poluter

Yes the cat makes a diff...BUT
Is your carb computer controled?

Carburated 84


(Gross Polluter?? Not intentionally)
Fortuantely we don't have the same restrictions here as you do in CA.

No the carb. is not computer controled. The previous owner installed and edelbrock intake and a holley.

Just heard from my son who's a mechanic in NJ and he said that the cats would not cause the HC & CO to be high, and being that it didn't fail for other gases, he suspects that a good tune up and premium gas would help it pass.

Regardless, I've got 30 days to drive it around and get it tuned up for the next inspection attempt.

I still can't get over how well the vette corners.


Does it still have the air pump? Very important to get the Cat to kick off and burn it all out. One of the biggest difference in a CA car and any other is the extra Air Pump equipment.

Get the engine as hot as possible, good quality gas, and you can actually shop for and buy different additives specific to improving emisions. You want to be lean, hot, and clean.

Now a days, you have so many choices in fuel injection systems. Expect to spend $2-$4K to get it right.

Good luck.
The engine does not have to be original. BUT it has to be newer than the vehicle.85 up AND it has to pass emissions for the year model of the new engine. I went through this with a 81 malibu wagon we put a 454in where a v6 was .
We had a similar problem when we had a larger engine than what the vin said.( When we still had testing here). I mainly did what your guy NJ said. Added some of that Octn. boost to a 1/4 of gas , made sure the timing was good and car good warm before we got there.

A little advance Like 2 deg & a small vac leak never hurt.( not suggesting that you cheat or anything)
Hum...... 2 deg adv. ,small vacuume leak & RXP additive.

That's the ticket.

But how is this cheating when the machine says it passes?


If the BOOK states 6 deg and you run the car @ 8 deg due to cam chain stretch, Harmonic balancer slip, milage, age, lunar position etc.

The car will fail for observed timing....

So that's cheating.

However in reality it's closer to running correctly
as per specs.

The vac leak....
it will lean things out a bit to make the engine run better but technically the vac system need to be completely sealed. Cheating..

And the additive... Well that's a gray call
the formulations of fuel & additives changes SO often who knows.

But ALL OF THIS.......

Is a great example of your TAX dollars
hardly @ work


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