Porsche 914 1.8L to 2.0L

[BTalbs]

What steps do I need to take to convert a 1.8L to a 2.0L? Do I need to get new heads? Do I need to get any machine work done on the heads? Or do I just need to get bigger pistons and jugs?

[raygreenwood]

You need the 2.0 cylinderz and pistons and a 2.0 crank and rods. The 1.7 and 1.8 had a 66mm stroke and the 2.0 had a 71mm stroke.

You "can" flycut the 1.8 heads to "fit" the 2.0 cylinders.....but it will require a little work to get deck sorted out.....and it will be more similar to a VW bus 2.0 but with slightly better compression.
It will be nowhere near the same as a 914 2.0 because the 914 used different head castings. Better splug plug angle, slightly different intake tract angle and ckmbustikn chamber shape.
But.....I say similar to a bus 2.0. If you get the compression right and cam it properly it will run very well.

To really make it work its best with this combo.....if you stay with injection....either D or L....use 914 2.0 intake runners with a 2.0 bus plenum and TB or a 412/914 plenum with a bus 2.0 TB.
You will also most probably need new pushrods ut just check the geometry. Ray

[914werke]

Lets start with a few questions?
What are you starting with? 1.8L
Carbs or OE FI (which was L-jet)?
If Carbs was the cam changed?
The answers to those Q's will help lead to your best options.
As already described to change a 1.7 or 1.8L to a 2.0 requires splitting the case and swapping the crank/rods.
Heads while not as good as the 2.0 variety will work w/o modification.
Another possibility to consider is going big bore -> 96mm =1911cc's.
no splitting the case, some CR and valvetrain work will net you as much as a stock 2.0L.
Diff than the stock 2.0L, slightly less tourque more revvy.

[malcolm2]

Depends what YOU want. Do you want a true 2.0? Then you need to get a crank, P/C, Heads, cooling tins, correct injectors and DJet stuff (if FI). If you are just looking for HP, then you can pick and choose.

I went with the 1911 cc set up. Uses the same 66mm crank as a 1.8, just 96mm pistons. that is the only change and I went from 1756 to 1911. The heads can be changed, but don't have to be....

You could just put the 2.0 sized valves in. That is where you need head work. IIRC the 93mm pistons and the 96 have the same cylinder OD, so cutting there would not be needed. But check my memeory on that. The spark plug hole does not have to move.... but it won't be a true 2.0.

Have fun.

[raygreenwood]

Or you can simply buy New heads on new castings from HAM inc...that have been CNC modified and had proper welding done to be exact replicas of three bolt 2.0L 914 heads.

They have exact combustion chamber shape, valve size, plug angle, three bot intake pattern etc. Not cheap...but worth every penny...and the new castings from what I hear do not have the cracking issues of the original 2.0 heads.
Ray

[Wolfgangdieter]

Very informative thread. Is changing the cam from FI to one better suited to carbs worth cost (i.e gives performance benefits?) What is best choice for a distributor? Should 009 be considered at all? Can FI distributor be used?

I have both a converted 2.0L engine with the 3 bolt heads but 1.7L case and dual Holley-Weber dual throats and a 1.8L 914 with bus duals Solex carbs. Both have been sitting and need to be gone through. I'd like to rebuild both - one would go in CMC Speedster and other in a Dolphin Mod-T buggy.
_________________
CMC '57 Porsche Speedster Replica and Dolphin boat tailed full pan VW MOD-T Street Buggy

[raygreenwood]

[BG`s`71sunnyfun]

I have original 914 wheels to put on my `71 convertible bug. A while back I
had seen a seller that had seemingly multitudes of the necessary lugs that I
needed for that application at quite a reasonable price. unfortunately did not
grab those at the time, and now I don`t see that seller in the wheels section.
Does anyone know about that or where to get these longer lugs? Thanks,

Brad:)

[bluebus86]