Greetings.
Got surging problems below 4k rpms.
I got 08 SDR only with FMF carbon slipons with no db killers. All others stock.
I have o2 eliminators installed but realised I could have used tuneecu to turn it off, as well as SAS.
I don't know yet what map I have as the original owner did not know.
I plan to use tuneecu and find out which map and maybe use a different map, and turn off o2 sensors and SAS.
but which map should i use for FMF muffler only mod.
08-10 US SDR Akra Smoothened
or
08 SDGuysCustom possibly the best map for aftermarket pipes .hex
or
should I just do a custom dynotune?

Can't use my map (Guys) dude as that is for a SD not an SDR!!!
I recommend you read up before you play as tuneecu is not a toy and thinks can go wrong if you like load the wrong map!

SD and SDR 08 has different engine insides hence the bigger HP output of the SDR model.

Dynotune is always the best option as every engine is different. My 990 changed from crap to gold with a proper dyno tune.
If you can afford the dyno session with a decent tuner do it, worth every penny!

Try James' (Jocke's) map.