Uncontrolled revving and lack of power kinda sounds like you've got an air leak somewhere.
The K series can't deal with air leaks very well - did you plug all the vacuum hoses back in, including the brake servo?
That's the one that gets me every. single. time.
Right now the K powered freelander is running beautifully... the RX8 has started playing up though.
Left it too long between runs and I think the battery is goosed, dash lit up like a Christmas tree, electrical gremlins all over the shop and it's suddenly taking an age to start.
Usually I'd be worried about engine failure bla bla but this was kinda sudden - think I need a new battery and a proper storage charger.
Doh! Doh! Doh!!!!!!
Was prepping the wifes K series for MOT and guess what? Yup, header tank was empty! No idea why as I checked it a couple of weeks ago and it was fine, so filled it, bled it and started looking for the leak. No sign of leaking water anywhere, even took off the undertray and checked all hoses and still no sign. Have driven a hundred miles or so since and no probs so hoping it is a dodgy header tank cap. I heard it hissing at one point as the engine was cooling so changed it and fingers crossed.
Anyway right now I feel your pain.
The scoring you mentioned look acceptable. The cross hatch pattern is perfectly normal, added at manufacture to bed the piston rings in. It's presence shows that little cylinder wear has taken place.
I find the marks for TDC very confusing on these engines. When you pull the crank pulley off the mark seems to point to a different position.For your lack of power. I'd be double checking the cam timing. The crank pulley mark has been known to be in the wrong place so the locking dowel in the flywheel is better. The cam pulley markers aren't much more accurate either. It's much better to use the actual valve lift points and a timing disc to get a true timing figure.
The actual timing marks used aren't at TDC. They are set at 90° BTDC iirc. This is done to give a "safe" area for the cams to be turned during the timing procedure. However it means that timing is reliant on accurate marks, which isn't always the case. It's quite possible for either cam to be advanced or retarded by 1 tooth which is about 7°iirc. The engine will still run but not at optimum performance.I find the marks for TDC very confusing on these engines. When you pull the crank pulley off the mark seems to point to a different position.
This page is very good and worth a look.
http://forums.mg-rover.org/showthread.php?t=395705
You're one tooth out mate, probably on the exhaust cam. When fitting it I found I had to crank it back a bit (clockwise) so there was enough slack to let me fit it. You'll never stretch the belt enough to get it around the exhaust cam if it is in the correct position. Then with the belt on I tightened it so the belt could go around the inlet cam. It is a pig but needs to be right.
If you shine a torch down between the two sprockets, there's a line on the plastic that the two marked teeth on the sprockets should line up with.
Other than that, use a straight edge - it should line up with all the inner and outer marks if you've done it correctly.
This can be a right bastard to time properly if it fights back - I always time it by putting the bolt back in the timing pulley without the aux belt pulley, putting the belt on and then spinning the crank twice. Check, check, recheck.
If it's a tooth out or so, it'll jump out noticeably after the second rotation.
Also, don't turn the crank backwards during timing - weird things happen. If you miss the timing marks, go around again.
And finally, when checking the timing marks on the crank, don't do it by eye as you can't get your head in the right place, use the camera on your phone from the wheelarch or closer - in line with the crank. If you do it by eye the crank can look perfectly aligned but will be half a tooth out of place.