Here is where my engine stands now:

http://www.youtube.com/watch?v=tzaFK9lQlqA

Would the colder weather (about 31F when I shot this) make it idle different? Back in July when I blew the oil seals, it wouldn't run like this period (without my foot on the gas).

Getting a rebuilt motor, parting out my old one (if it isn't seriously messed up inside and scoured)

What differences are there in engine mounts? I'm getting an S5 engine, and putting it into an S4 chassis. Huge difference? Or is it only the turbo motor mounts that are different from the N/A motors?

 

If you plan to part out what is good, i wouldnt start that motor again

 

It's being pulled this weekend, will sit till then.

 

All motor mounts are the same.
I hope you mean you are swapping your s4 accessories onto an s5 short block, otherwise you are in for a world of headaches.

 

I'm getting the S5 engine, engine harness and ECU, but I will also have everything from my old engine/harness

 

your best bet since youre starting with s4 is to just use the s5 keg and all s5 electrical components. otherwise have fun..

 

Keg? I'm assuming that is the rotor housings and ends? What's the difference between the S4 and S5 NA? They're both 1.3l but they have about a 20hp difference (supposedly).

 

the rotors themselves are different and have different compression ratios.

 

If you take advantage of the S5 engine's VDI system, yes. But that is beyond the scope of a simple swap, but not too challenging to do.

 

Ok, I'm kind of confused. I can put the engine in there with no mount problems, and I know that most of the electrical system is different, but what should I keep and what needs to be replaced?

This is correct[?]:

http://www.rotaryresurrection.com/2n...o_s4_swap.html

Things you MUST keep
(originally on the old engine, which plugs into the car) are:

Throttle body with TPS
Oil metering pump and front cover
Wiring harness with fuel injectors
ecu
airflow meter
water pump housing, water pump, fan

Looks like it isnt plug and play, but it looks alot easier than my rb20 swap...