Any performance loss using 1.8 heads on 2.0 Options

[Badass43]

Hey Guys,

I bought an engine from the classifeds here and was told it was a good engine but have found out it needs to be rebuilt.

I need to know if I get 1.8 heads for this 2.0 will I suffer any loss of power?

I found a small crack on the one head I have removed so far. the crack is right next to the plug hole.
I know I should have this fixed if I reuse these heads but has anyone reistalled heads with these small cracks with success?

I can get these heads that are pictured that say they are 2.0 heads but they look like 1.8 heads. Do you think they might be 2.0 bus heads?

What do you guys think?

Randy

[Rav914]

From Jake's 1.7 > 2.0 conversion article:

"Other heads" that can be used with the 1.7>2.0 conversion:
Now that you have upgraded to the 94mm cylinders (or 96mm) you are no longer limited to the small 100mm OD registered heads of the 1.7 engine. This means you can bolt on a set of 1.8 or 2.0 heads and if you go this route you won;t need to do ANY machine work to the heads at all for them to match perfectly to the 2.0 cylinders.

Ultimately I feel the best heads for these 2.0 conversions come from the 1.8L engine. These have the largest stock valves of any OEM head and the lack of machine work that is necessary make them a bit cheaper, especially for guys that are choosing to work on a budget, keeping as much "stock" as possible. Of course you should have any head completely rebuilt with new seats added- If you choose 1.8L heads you can keep the valve sizes stock at 41X34, or you can upgrade the components to 42X36 (my favorite valve sizes for small displacement engines) and use our modern parts for the job.

The 2.0 Bus or 914 heads are also worthy units, but most of them must have repair work made because the Bus heads come from overworked engines that have been pushing 5,000 pounds for 30+ years. We stay away from rebuilding any heads that came from a Bus engine as most have irreparable damage or damage that will cost more than the heads are worth to repair. The 2.0 914 heads are the only real "Porsche" heads found on the Type 4 engine. They feature 3 stud intake manifolds, the largest chambers and their own spark plug location. These are the most rare heads and also the heads that have the weakest combustion chambers, 95% of the time they are cracked and require machine work and a full rebuild. They are the most expensive heads to work with- period. They will make the most power of any stock head, due to the plug location, valve sizes and combustion chambers but the performance comes with a cost."