1.8--->2.0 Big Bore vs. stock 2.0, Cheeper to build a Big Bore from a 1.8? Options

[thomasotten]

I need some advise as to which direction to take my project. I have a 1.8 engine that is already out of my car. It could use a rebuild. I was wondering, for a street car with miild performance increases desired, what are the pros and cons of rebuilding a 1.8 engine to a big bore 2.0, as opposed to just buying a stock 2.0L and rebuilding that? Would I come out about the same, cost and performance wise? Either system will have 2.0L heat exhangers/exhaust.

[Dave_Darling]

The 2.0 heads, in stock form, make better power than the other Type IV heads. They are, however, more fragile and prone to cracks. Particularly at the spark plug holes, and on the short-radius side of the exhaust port.

The other Type IV heads all seem to have more material in those areas and are more robust. You can probably re-work a 1.8 head so that it flows as well as or better than a 2.0 one, but of course it will cost you some money.

With a 94x71 motor (2.0), you will have 1971cc of displacement. With a 96x66 motor (1.8 with "big bore" kit) you will have 1911cc. 60cc isn't exactly nothing, but it's not a whole heap of displacement either. You can make either one the better performer than the other by throwing enough money at it...

I think the 1.9 is an attractive option, myself.

--DD