I have a 01 civic lx two door what will be the best swap I could put on it and a good automatic tranny.

 

If you want to stay with an automatic transmission, you're stuck with using a D17. You'll get slightly more hp from a D17A2 out of an EX model Civic... but the gains are negligible. If you want to gain noticeable hp, check the FAQ's thread on engine swaps. This has been covered before, countless times.

 

What will be the best k series and transmissions to put on my 01 civic lx

 

k20z1 or k24a2

 

I wonder if anyone has ever done an automatic K swap into an EM2/ES1/ES2

 

^ i really don't see the point of an automatic k swap... i mean, for the money you spend on the swap, you would think everyone would go 6 spd...unless you won the lottery or somethin and you have money to blow.

 

anything is better than your d17

 

In order for the transmission to fit, you'd have to do some notching on the frame rails. Also, you'd need to get the K20A3 automatic transmission axles, if you want to retain your stock brakes. It's a huge amount of work for an auto-swap, especially when you consider the necessary changes to the wiring harness.



I suggest doing some research. Start with the FAQ's here: https://honda-tech.com/forums/honda-civic-2001-2005-78/faqs-guidelines-read-before-posting-2101211/

"Best" is such a relative term, that its impossible to answer accurately without knowing more details in to what goals you're looking to achieve.