My question is there any measurable difference between the stock 1.7 and 2.0L banana mufflers?

I have a 1911 with weber 40's so it is not a monster of an engine.

On my car now I have stainless 2.0L exchangers and the stock banana muffler. I like having heat, the noise level is fine and it sounds good. I also have a set of perfect 1.7 stainless HE and an early stock banana type muffler. I also have 2 other options for the 1.7 a modified banana with the 2 straight pipes and a bursch with a glass pack (LOUD). I wouldn't mind having the option to run different mufflers periodically but would likely run the stock system most of the time.

Stay with what you have. Banana mufflers only fit to 2.0 exchangers. SS 1.7 and 2.0 have the same size pipes.

There is a banana-style muffler for the 1.7 style exchangers.

The conversions of banana mufflers to center-outlet are RATHER LOUD. I ditched mine for a Bursch, in fact.

The difference from the driver's seat between the 1.7 SSIs with stock-type muffler and the 2.0 SSIs with stock-type muffler is too small to notice, IMHO. In theory the 2.0 one will flow better, but in practice it doesn't seem to be enough to measure.

So yeah, stay with what you have.

--DD

Agree with the previous posts, also if you go with the 1.7 SSI's and another muffler, you will need another muffler hanger ( one for the fit of the 1.7 HE's). 2.0 and 1.7 muffler hangers are physically different.
Tom