What is this turbo?

[caterpillar]

tooo small anyway....

[prj]

400-420hp turbo on pump gas, and full boost around 3800 rpm in 3rd.

Looks like bog standard K26/K27 to me.

[Colesy]

If the smaller dimension was 45.6mm it would be a 3060. If it was 48.3mm it would be a 3064.
Measure right at the top of the wheel and see if its nearer the former dimension.

Have had another measure, right at the top is 45.98mm so looks like a 3060 then.

[Colesy]

400-420hp turbo on pump gas, and full boost around 3800 rpm in 3rd.

Looks like bog standard K26/K27 to me.

Thanks, good, that's what it was sold to me as which is a good start.

[twoqu]

Have had another measure, right at the top is 45.98mm so looks like a 3060 then.

Measure the tip width of the the larger dimension near the plate. That might help.
I cannot find a wheel with that dimension.
I was told by a reputed individual that a 3064 with a #6 would do 400bhp. The favoured comp wheel appears to be the 3072 which is what I believe MTM used to get the 428bhp of the RSR in conjunction with an #8 turbine.
Think thats what others such as Sonic/Steve H are running.
Once you identify the wheel you should be able to get a compressor map that should answer the question to how much it will make assuming its not some odd ball truck/diesel one!

[prj]

The KX500 is a fair bit bigger, it can do 2 bar to redline easily.

[twoqu]

The C dimension is what I was after!
3060 should be 6.3mm.
3064 should be 7.4mm.