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Hi Folks

My big end bearings on my 2lt '74 Nord went to Alfa heaven. I am thinking about making some upgrades to the engine while everything is in pieces. I just don't know if it is worth it at the end of the day.

I am considering skimming the head and some hotter cams. What power gains could i expect from these modifications? Anything else that needs to be done if these modifications are done?

Thanks for the help.
 

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71 Berlina 74 GTV 17 Giulia Q4
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First off, how is the crank?
Motronic pistions for sure, much better dome design, more efficient=more power.
I'd be interested to see what others have to say on this but at what point would adding say higher lift cams, etc run into the limits of how much fuel the spica pump can get into the engine to take advantage of all the mods? or put another way... at which point does one need to talk about getting an HP pump from Wes?
 

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You can do almost anything to it if you are running Webers. My Spider is faster than my GTV6 and it has perfect manners. I agree with gigem75 that you should probably contact Wes Ingram if you want a hot SPICA engine.
 

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I have Motronic pistons, a prepared cylinder head, RJ cams, Shankle headers, 123/MSD ignition, and Webers with 34mm venturis. My understanding is that skimming the head is at least as good as installing Motronic pistons - I would go that route if I were starting over. I tried 5 different camshaft combinations and my current setup is by far the best RJ136 intake and RJ785 exhaust. I also think that cams make the biggest difference.
 

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It is my understanding that the higher the "dome" of the piston, the less efficient it is. So, I would go with the stock pistons and shave the head to increase compression.
 

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71 Berlina 74 GTV 17 Giulia Q4
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Which is why the motronics have a flat top, well as much as a nord can have a flat top. They also have higher compression but I suspect the greatest advantage of motronics is the shape of the piston and flame propagation. Once you shave the head you can't get that back and if in the future you have shaved it to the max height limit you will need a different head whereas if you just take the minimum amount to get it flat and a good sealing surface you can get a couple of rebuilds out of the head, something you or a different owner would appreciate. Not to mention the gas we get is not going to get any better, just worse so a high compression engine for track sure but for a daily/street driver it'd be a drag not to be able to get decent gas for it or have to retard the timing so much all the other mods don't have a chance to do what they do best. just my 02
 

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You should be able to run 10.5 on pump gas. I have Motronics and I tested my engine for pinging when I was trrying out the different advance curves in the 123ignition distributor. If an engine is going to start pinging it will be a full throttle, high load and medium revs. I used a 50/50 mix of premium and mid grade gas so that I would have a safety margin with premium. I was able to set the max advance to 40 degrees with the Bosch 041 curve with no pinging and 38 degrees with the Shankle curve. I will probably skim a little from the head on the next rebuild to get me to 10.5.
 
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