I've purchased a Redline Performance 13b turbo. However I'm remote to the engine (Im in NZ and the engine is currently in the US) and can't identify it. I'd like to purchase a replacement turbo (if one is needed) prior to shipping it to NZ.

Secondly if the turbo is inadequate then I need a recommendation on what I should purchase.
It's going into a single seater offroad race buggy. As such I need a broad spread of torque and very quick throttle response. I'd also like to get around the 450whp mark running avgas (100 actane). Basic research is pointing towards the Garrett GT40'ish sizing.

 

I've worked on several of those setups. They have very mismatched turbo systems. The turbo is usually a t4 oncenter p trim in a .7ish, or .81 housing. Turbine housing a/r is too small usually, and the on center part is bad too. Compressor section is usually a v1/v2 in a to4e compressor housing. Our td61 would be what you are after, usually makes 450rwhp around 17psi with an extremely broad torque curve. We could also stuff it into the same compressor housing and you could reuse your turbine housing if you really wanted(bolt in affair)...