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Discussion Starter #1
I tried a search and did not find anything obvious. Can someone comment on the changes to the Spica system for 1981 on a Spider. Is 81 the year of the single butterflies, does a 81 run/feel significantly different than a 78 or 80

Thanks

Len
 

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Discussion Starter #2
A search on the spider page shows that this is indeed the single butterfly, does this really result in a difference in feel around town in normal driving. All the articles I have been able to find all indicate power and torque within a couple of HP or ft-lbs. Is drivability any different between the multiple butterflies and the single

Len
 

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But Mad North-Northwest
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Yes, '81 is the infamous "monofarfalla" single throttle plate SPICA.

Given that you're in CA, I wouldn't even consider buying an '81. The combination of SPICA, requiring smog, and being unable to legally modify the monofarfalla intake is just not worth it. Best thing that can happen to that car is for someone to take it out of state and modify it to Euro-spec Webers.

Your best bet is an '82-on car as they're still cheap, reasonably plentiful, and the Bosch FI isn't too bad to smog. It'll just run a lot better and be easier to maintain overall.
 

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Roadtrip may chime in with the gospel on the differences, but yes, a single throat throttle, cast airbox needed due to the heat of EGR (for the first time) air filter over on the exhaust side of the engine, different manifold, different Spica pump 3D camoid, different (three tang instead of two) lockring on the fuel cutoff solenoid. Also different setup for idle air, requiring a couple special tools.
If I had a good running one with good smog numbers, I wouldn't mess with it, I'd run it til it didn't pass smog any longer. Current cats are better than period cats, so if everything's working it might pass fine.
Andrew
 

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Yes. Single butterfly throttle. Every known smog add-on know to man. I'd avoid an 81 unless I could convert it legally to the quad intake.
 

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Discussion Starter #7
Thanks, what parts are required to go back to the 4 butterfly system. any chance a CA car could pass smog with a new cat, assuming the visual does'nt fail.

probably better of going with a 82 or 74. I had a 83 Spider and 84 GTV and want to get back into an Alfa

Len
 

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But Mad North-Northwest
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Thanks, what parts are required to go back to the 4 butterfly system. any chance a CA car could pass smog with a new cat, assuming the visual does'nt fail.
Don't do it unless you want to try to keep seeking out dodgy smog guys. It'll cost you a bunch of work and parts to convert it, and if you get caught on the visual you're going to be stuck with a car you can't sell in CA.

If you want that body style, just buy an '82 with Bosch. Or you can get a '76-'79...you'll still need to smog the SPICA, but at least you'll legally have the better intake layout. Either one of those options isn't going to cost you much more than an '81 and is going to be a lot easier to deal with.
 

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To answer your question, for the swap you'll need to upbolt the intake manifold, pump, air box, air filter, EGR, and swap in a manifold, pump, airbox, etc. from an earlier car. Exhaust changes likely too due to EGR connection. It'd be a lot of work. In CA I wouldn't make the switch, fearing getting busted at smog time.
Andrew
 

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Discussion Starter #10
Thanks, no way I would do a swap in CA, but was interested in what all is involved.

I'll probably look for a 74 or earlier.

Len
 

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1981 was also the first year of the 4.10 rear axle ratio, which blunts acceleration considerably.

I had an '81 many years ago that ran well with the Monofarfalla plenum but with all the other smog gear removed (long before I got it). I understand this isn't an option in CA but technically they can be made to run fine with the Monofarfalla set-up.
 

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Could the ERG and Air Pump be simply disconntected/plugged? I'm in the process of collecting the parts (may have found a complete set-up with pump tointake/ injectors) to convert my 1981 to an earlier set-up. I have a couple of people say its a straight forward change-over. In fact, some have said that you "can" use the '81 pump with the multi-butterfly system. Others...not so much.

Geoff
 
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