Alfa Romeo Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
47 Posts
Discussion Starter #1
Is there such a thing as a single Weber carb conversion for a SPICA injected Spider (as opposed to the dual carb setup)? Before the purists get on me for even asking, I have a reason. I am restoring a 79 for me. I am going to restore my 78 and give it to my daughter as a graduation present in a couple years. I am keeping SPICA on mine, but a single carb on hers would cut back on performance, which for a 21 year old is a good thing. It should also be easier to keep maintained and tuned. A side benefit would be a complete SPICA system sitting on the shelf in my garage waiting for things on my car to fail.

-Wayne
 

·
1966-2013
Joined
·
13,741 Posts
You might get away with the Solex single carb manifold with a Weber on it. (it seems someone offered a single Weber as a replacement for the Solex, but I can't quite recall right this second who it was)

Then again, they might have a single Weber rig out there somewhere as stock.
 

·
Registered
Joined
·
8,982 Posts
but would it have any performance??if you do not like your spica..insted of useing a carb.. why not just get a bosch L-jet off a dead car and instale it..not really hard..
 

·
But Mad North-Northwest
Joined
·
10,085 Posts
I don't think you're really thinking about this right, Wayne. I mean, it's what, 120-130HP in stock SPICA form? That's not exactly too much power for a 21 year old. A Rabbit has more power than that. My buddy's freakin' 10 year old Civic has more power than that.

You'd be better off teaching her to drive it properly, since darned near any other modern car she drives is going to be faster. Besides, it's not like she's going to be doing burnouts in it even with the SPICA. Cut the power and all you're going to do is make it suck to merge onto the freeway.

If your main concern in this is safety, you might rather focus on something more significant like...oh, I don't know...that it's a 30 year old convertible with no air bags, no roll bar, no ABS, and minimal safety features, perhaps? Engine power should be the least of your concerns.
 

·
Registered
Joined
·
2,984 Posts
There was Single Carb setup for some of the older Alfas.
I think all you need is that setup. I think it used a downdraft. but as far as I know it will boltup. and I do not even think you will be down very much power.
The extra CFM only comes on in the Hi RPMs anyways.

If you can not get the whole setup cheap. I would say go EFI, carbs are a pain. MPG with the cost going up every day would be the thing to try for.
 

·
Registered
Joined
·
532 Posts
Not to point out the obvious, but, there are two (actually 3) throttle stops on a Spica car. One is on the intake manifold itself, which limits rotation of the bellcrank, and the other is on the floor of the car, to limit travel of the throttle pedal itself.
 

·
Premium Member
Joined
·
21,383 Posts
There were single carb 1300 and 1600 engines, but never for 1750 or 2000 engines. No reason you couldn't do it, as long as the carb was jetted properly. It would probably be smooth and torquey, but run out of breath at the high end. Single-carb manifolds are noted for causing burned valves on 1 and 4.

Andrew
 

·
Registered
Joined
·
1,056 Posts
There were single carb 1300 and 1600 engines, but never for 1750 or 2000 engines. No reason you couldn't do it, as long as the carb was jetted properly. It would probably be smooth and torquey, but run out of breath at the high end. Single-carb manifolds are noted for causing burned valves on 1 and 4.

Andrew
Back when I worked for a living (about 40 years ago) I serviced quite a few single carb Alfa's. I don't ever recall any special problems with those cars. They had a Solex 2bbl carb with progressive opening. The air inlet was an odd oval shape so I bet it would be tough to get an air filter that would fit. There may be a Weber downdraft retrofit carb for the application.

Back in another life I have installed dual down draft Weber carbs on cars like 240Z's. One would think that the dumb looking carb adaptors would hurt peformance but I couldn't tell the difference.

Maybe someone offers a dual Weber downdraft adaptor kit for the Spica manifold. Might be worth looking into.
 

·
Registered
Joined
·
47 Posts
Discussion Starter #9
I don't think you're really thinking about this right, Wayne. I mean, it's what, 120-130HP in stock SPICA form? That's not exactly too much power for a 21 year old. A Rabbit has more power than that. My buddy's freakin' 10 year old Civic has more power than that.

You'd be better off teaching her to drive it properly, since darned near any other modern car she drives is going to be faster. Besides, it's not like she's going to be doing burnouts in it even with the SPICA. Cut the power and all you're going to do is make it suck to merge onto the freeway.

If your main concern in this is safety, you might rather focus on something more significant like...oh, I don't know...that it's a 30 year old convertible with no air bags, no roll bar, no ABS, and minimal safety features, perhaps? Engine power should be the least of your concerns.
My main concern is dependability. A simplified fuel delivery system would require less maintenance... This is important for a young woman going out into the world where daddy will not be there to keep thing tuned and most mechanics these days probably think SPICA is where the sound comes out on an Italian radio.

-Wayne
 

·
Premium Member
Joined
·
2,811 Posts
The Solexes used on the single-carb cars were fine, as long as they did not have a lot of miles on them. The spindle holes tended to wear and allow air leaks. Just doing the standard rebuild did not help, and the driveability got progressively worse.
One good replacement (for Giuliettas, anyway) was a properly-jetted Weber 36DCD.
 

·
Registered
Joined
·
120 Posts
Weber 36 DCDs and DGVs have been successfully adapted to original Alfa intakes for Giulietta and Giulia models. The only question on these older Alfas involved hood clearance and air cleaners (minor issues). If smog laws will let you do this swap I think you, and not your daughter, will be coming up with the short end of the horsepower stick. I did the Solex to 36 DCD swap on my '62 Giulia 1600 and got very near dual Weber 40 DCOE numbers (I also swaped the stock cams for cams from a stock '73 2L). Picked up over 14 HP from the Solex equipped w/ the same 2L cams. Major attitude change for the car!! My advice, do the swap but you keep the carb. car!

The old intake manifolds and DCD/DGV carbs can be frequently found on ebay.

Randy Harris
'62 & '67 Spiders
'78 Sport Sedan
 
1 - 11 of 11 Posts
Top