Getting back my dad's Giulia Sprint in the next couple of days. As I recall, there used to be a popular upgrade to 1400cc for the 1300. The lady selling me back the car insists that her late husband upgraded the 1600 to larger displacement while keeping the original block. So, question is, has anyone heard of a big bore or stroker modification for a stock 1600?
Well.. Yes and no. It is possible to bore a 1600 to 80 mm, if you can stand paper thin skirts at the bottom of the liners, been there done that. If you have money to finance a machinist's kids college education, you can open up the liners bores in the block to take shortened or custom 1750 shorty liners that can be opened up a little more.
With cranks, about anything is possible. I have been exploring big bore 1300's that require short stroke crankshafts, 67.5 or 68.5 mm. I found that custom stroker or de stroker are ONLY a couple of grand for real good ones. Limiting factor here is rod big ends hitting the inside of the block. Splitting them at an angle helps a little. Carello can make you custom ones, $1000 + each, but you only need four.
Finally, Alfa offered the following 1600's; regular flavored 78 x 82, or ( ) 86 x 68.5, using the 1900 mono-liner set up, though I believe this used a special 1750, not 1600 block.
If you are a machinist, or have money, about anything is possible I suppose! ( I didn't tell you about the head work, or pistons, did I?) Gordon Raymond
Last edited by Gordon Raymond; 03-23-2008 at 07:07 PM.
Reason: left out a little.
Boring the 1600 liners to accept 1750 pistons is a pretty standard modification. While the liner walls will be 1 mm thinner (you are going from a 78mm bore to an 80mm), for street use they will still be plenty strong. Displacement increases from 1567 to 1649.
Stock 1750 pistons will work OK, but as Gordon said, you will need to do some head work to accommodate the larger piston diameter. Use modeling clay to check clearances.
I did this for fun on my Giulia spider, and the resulting engine runs great. Given the light weight of these car, the stock displacement is very adequate. My point being that the car doesn't exactly "cry out" for this modification. But, if Ian's car already has the mod, then great - most likely it was done with 1750 pistons.
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Jay Mackro
San Juan Capistrano, CA
Big bore 1600's?
Limiting factor here is rod big ends hitting the inside of the block. Splitting them at an angle helps a little. Carello can make you custom ones, $1000 + each, but you only need four
. 
) 86 x 68.5, using the 1900 mono-liner set up, though I believe this used a special 1750, not 1600 block. 
I suppose! ( I didn't tell you about the head work, or pistons, did I?)
Gordon Raymond
Linear Mode
