So just how good are these SBM engines

Howdy.
I'm new to Mopar had Fords all my life. Just finished my first engine - 360 + .040 KB190 pistons, Racer Brown ST 21 solid cam, Std "J" heads but with 1.96 & 1.60 valves,decent springs etc. Also has an old Vertex magneto and a toilet style mechanical injector. Will be running methanol in a slingshot dragster with a 904 TF 4800 stall converter, 4.30 gears and a 31" slick. A very basic budget deal. I was impressed by the Standard rods and just up graded the bolts. The block looks beefier than SBC or Ford windsor but had a fair bit of crap casting flash. Liked the 273 adjustable shaft rockers I picked up at a swap meet. Don't like the exhaust ports and couldn't believe the original pistons were dished tops and .125" down the bore! Anyhow just have to sort a set of headers now - anyone have a set or some zoomies that they would part with? Chrysler stuff is scarce here in Australia - most shops don't want to talk to you about anything other than SBC or Ford. Read a few books looked at the web - including some here, and applied a life times experience and I hope it works out OK. Bought some stuff from Dave Hughes very happy and even with freight cheaper than here in Aussie. About to by a couple of bits tonight from Alki Digger then ready to fire this thing up for the first time in a week or so.
What is my combo good for? Who has some first hand experienced Mopar input.