Help with 340 compression + cam change

I run a 800 AVS on my 410 stroker 5 speed manual. My brother came over with his brand new 600 AVS 2 and bolted it on for a try. It had a bit better light throttle response but lost a heap on full throttle. Just did not smoke the tyres when you flattened it in second gear as per the 800. I know this was out of the box but it did not have the seat of the pants feel.