What machine work needs to be done on an early 1.7 case to convert it to a stock 2 ltr motor? thanks for any help, Jon

Well, I am not sure what they make any more, but they used to make slip in 96MM cyl. for a 1.7l case.
The crank, and rods should need no machining as they sacrificed journal size to get the additional stroke.

So, depending on what you get for Cyl, you would need to machine the case to have the cyle fit in and that is it.

The heads would need machining as well, but you didn't ask about that, so I figured you have that covered!

Good luck, welcome and I hope that helped.

None

The 2.0 914 was achieved by using the old time procedure of off-set grinding to increase stroke with a 66mm crank to 71mm,the big end journal was reduced in diameter in the process ,and then with an increase of 1mm in the bore made under 2000cc .
I understand this development was done by Porsche engineering genius Hans Mezger (RIP) which would have been a "walk in the park for him "considering the amazing race engines he designed.
I honestly don't now the benefits of doing this conversion because I've never done it,some say a big bore 66mm crank motor is better as it revs easily in our (light) cars.
Engine builders please chime in,rant over

Short answer is none. And 1.7 case apparently has some more desirable properties in terms of structure and durability. I just did a 2056 out of a 1.7 case.

Longer answer is - it is still a good idea to get your case checked for bore alignment and ensure the registers (holes for the cylinders) match within .002" of each other. So it's still a good idea to have access to a machine shop nearby that knows these engines.

I think the shorter stroke set up right is more fun to drive. I.ve driven both.

That means a 1911.

seems to me I remember that there is a bit more relief in the 2.0 case where the piston skirts fit, and we had some problem years ago with the 2.0 NPR piston skirts interfering with the 1.7 case, yet the stock mahle 2.0 pistons fit the 2.0 case just fine.

Only a memory so do not quote me on this one.

I believe the thinking behind using the 1.7L case is that the 1.7 case is less stressed and therefore less likely to be damaged or need a lot of machining to be usable.

Jake Raby has also mentioned they had better metallurgy and he uses them to build his big hp engines.

I have a 72 1.7 that's now a 1911 and pulls just like a 2.0. It is noticeable.

What is the 1911cc configuration often referenced on this site?

2.0 head chambers or 1.7/1.8 head chambers?

Stock cam, RAT 9590, WEB cam 73? (Assuming using stock yellow injectors, D-jet)

Has anyone ever built a 1.7 with relocated spark plug (to 2.0 location) or with WEB cam 73, RAT 9590 or is that displacement not large enough to gain from those improvements?

Basic 1911 is 96mm P&C (slip right in, with no machining) and stock 1.7 crank (66 mm). Changes the stroke ratio so it revs up quickly. If you swap to the 2.0 crank (71 mm) you get 2056.

Excellent reference: http://www.914world.com/bbs2/index.php?showtopic=141448