One of the great reasons IGT is so fun to Race/Bash is because it’s hard to put a “wrong” Engine in it.
Many of us have a old 3 or 5 port .21 or .28 laying around from a buggy and they just slide right in and work great, after all these are buggy’s with a 2speed and slicks. At worst you might have to change your pinion gears to adjust for the type of power your engine has.
I would stay away ALL RTR Engines they tend to be more hassle then the few dollars u save is worth.
Pick your favorite Engine and let it rip….

I also agree the Werks is a very good engine for this class.
TecnoPower has a few .21 engines left at Amainhobbies cant get a better engine for the money. Less then 200.00
Whatever engine you decide on just remember the one rule,
Smile when you pull that trigger.