MG ZR: Cams & Maps

[devils_fuel]

Okay a bit of a bombshell of an update:
A big thanks to Jammapic goes out today for helping get some more insight into this car with a compression test and taking me out in his gti +hdi, both of which sound amazing and pull like no mans business. Just a shame the roads were wet so the power couldn't be put down fully
Plugging the car into a reader showed the map sensor being a bit off with readings which could explain the blip when you press the throttle
The compression test showed that although the cylinders were within tolerances of each other 3/4 ran at 250psi and the other 240....a standard engine should be 160psi.
There also appears to be no repair gasket so James is thinking that the head has been skimmed and no gasket to make up for the loss of material has been put on resulting in the pressure bumping up making the ecu retard the timings so as not to knock orrrr the exhaust camshaft is timed badly and holding in the exhaust gases for too long. Either way something is afoot.
Removing spark plugs as well showed a lot of oil in some of the holes covering the plugs, possibly a rocker gasket which have been like that for a while since there's bathroom sealant around the area it should be.

In terms of future power mods, I want to stay n/a maybe with throttle bodies or something But for now it looks like it's going to be a bit of work getting it right again

Something's more than afoot Steve, really sorry about the bad news! As it's a rover I'd get the head off ASAP and get it sorted before things break and cost mega bucks .
Once it's running bang on again any mods will make a difference