I have a 74 1.8 that will soon be 2056. I have my original 1.8 heat exchangers and stock muffler. I also have a set of 2.0 exchange and a Bursht muffler but this set is rusty.
is there any advantage in using a 2.o over the 1.8 ?

a stock 1.8 set has a slightly narrower I.D. than a stock 2.0 set - but i doubt there is a feel-able performance difference.

my guess is the 2.0 set would be slightly lighter too.

jim

shameless plug - see my 1.7/1.8 sshe set in classifieds.

I think that the 2L exchangers have a larger ID, but that may just be the SSIs. The Bursch may yield a couple extra HP. Which one do you have - the one that looks like a conventional muffler or the glass pack? I can tell you that the glass pack is pretty loud.

I have the stock 2.0 heat exchangers and a Bursch that looks like a rust bucket. It's all surface rust but I don't know what's inside the rust

So the lower one is 1.8?

From what Jim has posted above, I think that if you are looking for performance gains, go with the 2.0 hardware. If your Bursch muffler is round, rather than oval, it is going to be louder. You may or may not like it.

What year 1.8, and what year 2.0?

All of the US-spec 75-76 914s had the same exhaust, whether 1.8s or 2.0s. The 74 1.8 had (basically) the same setup as the 70-73 1.7, while the 73-74 had its own exhaust.

The stock 73-74 2.0 version seems to be the best of the lot. The diameter of the exhaust pipes is larger than that of the 1.7 pipes. The 1.7 setup (same as the 74 1.8) is next best, and the 75-76 exhaust the worst.

All of the SSIs have the same diameter, which is larger than the stock 2.0 pipes.

A real header will outperform all of the above, but you lose all semblance of heat. (With one or two exceptions, which can be quite expensive.)

--DD