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Discussion Starter #1
Newish to me not running 1977 spider that I have to go over because it has sat for a long time and previous owner said that the car ran but it would cut out and be very hard to restart and I removed the plugs today and they are bosch platinums and all 4 are black from running rich and I wanted to know what a good starting point for Italian weber 40 carb jets are so I can pull mine and compare and thanks for the insight.
 

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This thread post 48 has a scan of the Shankle table for Weber jetting. Column at right has the most common 2000 jetting based on 32 venturis. I think Shankle created the adapters to install Webers on Spica manifolds.

What are the carb numbers? There are some varieties of the 40DCOE that were intended for very specific applications and that have weird progression holes patterns. They can be a challenge.
 

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Discussion Starter #3
Looks like I have 40dcoe 151 carbs and I have the mirelli electronic ignition with the GM regulator and wanted to know if that is a good or bad setup?
 

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go to the tech section of Centerline Alfa and find Weber data. Your jetting should be the same as 40DCOE32.
Your Marelliplex ignition is a good system if it is in working condition.
NGK BPR6ES are good plugs if you don't drive the engine hard.
 

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Thank you very much to all that have chimed in. I ordered ngk BPR7ES and hope that I did not make a mistake.I do run my cars pretty hard on the street sometimes.Should I be ok with this plug?
 

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Discussion Starter #9
Actually I ordered BR7ES. I read that the BPR sits a little lower in the head. Guy that I bought the car from didn't tell me that the mice liked his electrical system along with his plug,coil, and mirelli electrical wires to sharpen their teeth on and who knows what else.
 

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Just be careful because while the BPR or BP7ES are fine they protrude into the combustion chamber more than the B7ES. I'm just wondering why the previous owner had platinum plugs fitted. Usually nothing to worry about but I thought it was worth mentioning.
 

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Discussion Starter #11
The bosch platinum plugs were like welded in there and I had a heck of a time getting them loose yesterday. I guess a reason could be because the PO had let water pool in each spark plug area for some time that was bad enough that it left rust marks on the head and am keeping my fingers crossed that no water entered the combustion chamber. Not putting a bunch of money into this car till I see if I can get it going or not.
 

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Yeah they can really bind up. A small about of lubricant on the new plugs and don't overtighten. Plugs are mostly always over tightened.
 

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Discussion Starter #13
I used bp blast and tapped on the metal of each spark plug for a little while with a punch and hammer to kinda shock them a little bit and used a shop vac to suck out the bp blast right after I got each loose. I was sweating a little bit on #3.
 

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You have to be careful with extended nose plugs if you have oversized intake valves and high lift cams, in which case you have to index them. They provide better combustion than non extended plugs which is explained in the Bosch Automotive Handbook.

"6" heat range plugs will reach self cleaning temperature faster than "7" range plugs and are less prone to fouling if you make short trips in your car. 7's are better for plug life if you do hard driving, particularly with a leanish mixture.
 
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