Removing Smog Gear on a stock carb'd '80....Anyone?

Flash

Flash

Daily Driver
I'm sure this has been covered before but couldn't find specifics when searching the archives...sorry. If you know of resources in the archives I'd be happy to check it out; just post a link.
Anyway, I have to do my water pump and T-stat and thought while I had half the smog gear off it would be a good time to just remove it all permanently (I live in an area that doesn't require smog testing). The only thing I'm initially leary of are the side effects of removing the electrical connections to the carb and EGR valve. Are there ramifications I need to be aware of here? I feel comfortable with the fuel, vacuum, and water issues but if there are "tricks of the trade" to impart here as well, or any other words of advice, I'm all ears. TIA
 
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Hey Buddy, can you spare a tip?

I know this isn't the sexiest topic in the world but I was hoping to try and get this done over the weekend. Anyone....?
 
I transplanted a carbed 1500

I transplanted a carbed 1500 into a '74, and didn't carry over any of the smog stuff. I can tell you everything I removed/plugged.

The good news: It works fine, this is a simple honest engine that is easily tuned to run without its smog stuff. It's just a matter of disconnecting and plugging and removing the right stuff, then going back and setting timing, idle speed, and idle mixture. The engine runs better, and it is way easier to work on with all that snot out of the engine compartment.

The bad news: Because I was transplanting into a '74, I ditched the 28/30 DHTA that was stock on the carbed 1500 and used the 32 DMTRA that came with the '74. So if you have the 28/30 DHTA that is stock on the US 1500 and you want to keep it, I won't be able to tell you what exactly to do with your carb... and there is a lot of emissions stuff bundled into the DHTA.

OTOH there is no reason to use the restrictive strangling low-performance emissions-toadying DHTA on a desmogged car. If I were you, I would locate a 32 DATRA which is a simpler and better performing carb - and I or plenty of other people here can tell you how to hook it up. These are fairly common because they're what came stock on the 75-78 US-spec 1300; Matt lists them for $50.

Ideal would be the 34 DATR that came on European 1500 cars or its cousin the 34 DAT, but you won't find one of them for $50 in the US, and they'd likely want a European cam as well.
 
Heading in the right direction...

Thanks Eric; that's a start and more info than I had before your reply. My Haynes manual just doesn't always give me the detail I need. I ran across a link you posted to the on-line X workshop manual in another post and I think that's going to be a tremendous help.
Back in the day I desmogged my '78 but that was before engineers got the bright idea to combine the electrical system with the intake/exhaust system...Must have been the same person that combined numbers with the alphabet to come up with algebra! :dunce:
It's usually easy to see where a vacuum line or fuel hose goes and what it interconnects but not always so with an electrical connection/component. Looks like my weekend is set...now if it will just stay above freezing....
 
Dave... Once the car reaches...

... operating temp... the only difference between a car with operating smog devices and one without, is the EGR system.

Everything else will have been neutralized and is out of the picture. Only a portion of your exhaust gases are now being recirculated. How good is that??? Well, I don't believe the FI cars use it... if it was that good... why did they not keep it on the later models?

As for the 32 or 34 versus the 28/30 carb... I too went to a cheap 32 and used the tubes/rods from the 28/30 for a great tune. Get a 34 for if you can find one, but 32 are a notable upgrade for very little money.

Bottom line... all my smog stuff is off the car which resulted in an average of 4 more mpg, about 70 pounds less weight, and better overall performance.
 
Works for me.....

Thanks for the pointers. I guess it's time to break out the :hammer: and :drink:; not necessarily in that order!
 
Smog Removal

On my '80 X, I started removing the air pump and all associated plumbing and brackets, removed the entire EGR system and plugged the resulting coolant passage esposed in the block as well as the EGR hole in the head, removed the entire vacuum block assembly with 4 vacuum switches, replaced the intake manifold with its EGR fitting with a non-egr model (you can also plugthe EGR hole), replaced the exhaust manifold with its EGR fitting with a non-egr model (you can also plugthe EGR hole), replaced the chardoal canister with its multiple emissions ports with a simple 1 port model, replaced the carb initially with a 32 DATR, then with a 34 DATR, both modified to provide ported vacuum to the distributer. For esthetics, I removed the air pump timing cover and backing plate and replaced them with non-air pump units. The engine compartment looks better and the car runs great.

Dave
 
desmog

here a old thread about smog removal http://xwebforums.com/forum/index.php?threads/3831/ I removed all the old piping and plug all the opening a oil pan drain plug fits nicely in to the exhaust manifold. Do change out your carb. and if you can weld a plug into the water pump tube due to theirs a hose that run down to the EGR valve and plug the water passage going back into the block. good luck and just think it out of what you don't need EGR, Glup valve thermo vacume switch block all the small hoses.
 
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