engine

[Boydskyking]

I have a 1.7 engine and would like to convert it to a 2.0. Is this possible and if so what would it I have to do to do this .
Thanks

[beatnavy]

Are you talking swapping the engine for a 2.0 or rebuilding your existing 1.7 into a 2.0? Either way the answer is yes, it is possible and quite common.

Rebuilding your 1.7L into a 2.0 (1911) is straightforward conceptually: bore the case for the 94 mm pistons, get the stock 2.0 crankshaft (71mm), and have the heads machined to 105mm register size. Obviously more in terms of parts, machining, and other details, but it has been done a lot. This assumes your existing case and heads are in decent shape.

Are you currently or planning carbs or FI?

[Boydskyking]

No I am going to carbs can you tell me the best setup

[beatnavy]

That could fill a book (and probably has). Do some research, as there's plenty of info online. Having said that, for carbs most people seem to prefer twin Dellorto 40's or Weber 44's. Both setups are easily good to 2056, IIRC. Of those, Dellortos seem to be preferred by most for what is perceived to be smoother transition from idle to WOT. Do not go with a single carb whatever you do, as that's way suboptimal.

At this point, I check out. I'm really not a carb guy, but there's many people who can speak more to it.

[Dave at Pelican Parts]

There are several different ways to make a 2.0 engine. They are all doable.

First, you can find a 2.0 914 engine and bolt it in, complete with its fuel injection. (Or convert it over to carbs, since you apparently have those.) The dimensions are 94mm bore and 71mm stroke, for 1971cc displacement.

There are Bus 2.0 engines that have the same displacement, but lower compression and lower-flowing heads and possibly a less-aggressive cam all mean it makes less power. Not to mention the oil filler and dipstick are in the wrong location, and will require modification.

There are 96mm P&Cs that you can bolt onto your 1.7 to bring it up to 1911cc displacement. The ones that fit in the 1.7 heads are quite thin at the top and prone to distortion. It is usually better to fly-cut the heads (or swap them) to fit the 96mm cylinders that fit a 1.8.

You can swap in a 2.0's crank and rods and either get some high-compression 2.0 pistons to give you 1971cc displacement, or go up to 96mm P&Cs for 2056cc displacement.

Note that the real 914 2.0 heads have a better spark plug location and flow better than any of the other stock 914 (or VW Type IV) heads. So you are leaving power on the table if you don't get those. The 2.0 heads are somewhat more fragile, and like to crack around the spark plug bosses, so it's not the worst thing in the world to stick with 1.7 or 1.8 heads, and of course those can be modified with larger valves and such.

Anyway, it can all be done. You can build any displacement of 914 engine on any 914 crankcase. No machining required for anything with stock dimensions, and 96mm cylinders fit all but the 1.7 heads without machining also. If you're willing to cut into things, you can get more displacement and spend a lot more money...

--DD