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Discussion Starter #1
This topic has been covered here and beat to death before. I have a NOM 2.0Spica setup in my sedan. Never been fond of it. When it's cold out, runs like a champ. When it gets hot, hard to start occasionaly and never been able to find out mistery hesitation, loss of power under load and stalling with more hard starts.

Found my original weber carbs attached to the manifold that have been off the car for about 25 years. Started tinkering around with them and started getting visions of velocity stacks and glorious musical sounds coming from them at high revs. Why should I stick with the spica (which I think is the culprit) when glistening weber's are just a daydream away? Mechanically I think I would do better with the carb setup. Comments, insults, swearing is welcomed:p
 

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IMO, if one has to go out and buy a set of Webers then it'd probably be better to have the SPICA system repaired instead. However, if you already have the carbs...

How much of a tree-hugger are you? I suspect a properly tuned SPICA system will have fewer emissions and better fuel economy than carbs.
 

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ghnl said:
I suspect a properly tuned SPICA system will have fewer emissions and better fuel economy
Likely a bit broader powerband too, or at least that's my very small grasp on the comparative.

If it's purely a noise thing, you can put stacks and such on the SPICA intake.
It won't gain you any power (might even lose some actually as the stock airbox is VERY well designed) but it'll make cool sounds simular to carbs.
 

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Discussion Starter #4
I know that a properly tuned spica system is more efficient and makes just as much power if not more than the average carb setup. I know i'm going to get blasted for being the typical guy to blame a spica setup with problems I don't have properly diagnosed.

I just think carbs would be easier for me to maintain and understand better. So with that being said, what do you think is better for the average mecahnically inclined person?:eek:
 

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I might suggest that you try and diagnose what might be wrong with the Spica system. Could be a TA going bad, a sticking Cold Start Solenoid, or just grossly out of tune.

Tuning carbs is harder and a Spica system will stay in tune for a very long time.

If you do convert the system, don't throw any Spica stuff away.
 

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Discussion Starter #6
That's the feedback I've been looking from members. Personal experiences from both sides of the camp? Why would the carbs be harder to tune over the spica? I know that once a spica system is tuned right it will stay that way longer than carbs, but aren't carbs simpler in design with less things likely to go wrong?
 

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My Spica system has been running for 10 years without anything other than routine service.

It's not a super complicated system once you read a little and understand how it works. If you want some Spica tech material, PM me an email address.
 

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Discussion Starter #8
Done! sent you a pm.

I guess I never really wanted to give the spica a chance since sidedraft webers have a certain "cool factor" for me. That is why I want someone to talk me out of this ordeal.
 

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Not never gonna talk someone out of something they truly wanna do, but some convincing counterpoints can be had to mabe make one think about it a bit more and base things more on rational decision making rather than an impulse choice. ;)
 

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Webers are easy to tune. I have never tried to do a SPICA setup but the extra complexity makes me believe that it may be harder. Webers may be the only reasonable choice if you have big cams. I average 23-24 mpg from my Spider with Webers and Richard Jemisons 12.3 intake and 11.5 exhaust cams. Even if you have mild cams now, Webers will make it easier for you to go for more power in the future. SPICA is pretty much an open loop system - the fuel delivery is not influenced by the air velocity. Carbs have a degree of automatic compensation for engine changes because increased gas flow creates a greater pressure depression in the venturi and that produces more fuel flow.
 

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I have run Alfas with both Spica and Webers. I have read and followed numerous Spica manuals, including Wes Ingram's.

In theory, Spica performs better/faster/cheaper/longer. In practice, I found setting up a Spica system to be a lot like maintaining PC software: the manual says "turn screw A and RPM's will rise", but when you do it, RPM's don't rise - the engine stalls. Or whatever. My point is that the Spica pump is sort of a "black box" - it bugs me that I can't readily get inside of it and figure out why it doesn't behave like it is supposed to.

Today ALL of my Alfas run Weber - so, you can guess where my sympathies lie. Webers are dirt simple. You can re-jet them in place. They look cool. What more could you ask for?
 

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So, what size Webers and what size chokes are you proposing to use?

Webers are easy to tune halfway close and hard to get just right. Every jet/choke/ET change requires another investment, so don't be too sure that they will be the cheapest alternative. I shudder at the thought of the retail cost of all the Weber bits I have collected over the years.

Mike R
 
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