I've got a set of early 1990s Range rover heads to replace my standard P6 heads and I'd like some advice and to fill some gaps in my knowledge. This head has the single valve springs and the large valves and know unleaded compatibility (as do all V8s most probably anyway).
I'd like to fit the later style of valve stem seal which fits both inlet and exhaust valves as these actually work unlike the washer style guides in the head currently. Now in order to do this I can either replace the valve guides with those with a step in the side or the existing ones which are in good order can be machined.
Now the guides and seals are cheap enough and it's a guarantee that I'm unlikely to need it done again probably in my Rover motoring lifetime. However Am I correct in saying the valve seats must be recut and possibly replaced to match any newly fitted guides?
Is the alternative that the guides are machined in situ (is that possible?) and the valve seats left alone, merely needing a light grinding in of the valves on refitting to ensure a good seal? If so, how much (length and width) needs to be machined from each guide?
Advice please.
I'd like to fit the later style of valve stem seal which fits both inlet and exhaust valves as these actually work unlike the washer style guides in the head currently. Now in order to do this I can either replace the valve guides with those with a step in the side or the existing ones which are in good order can be machined.
Now the guides and seals are cheap enough and it's a guarantee that I'm unlikely to need it done again probably in my Rover motoring lifetime. However Am I correct in saying the valve seats must be recut and possibly replaced to match any newly fitted guides?
Is the alternative that the guides are machined in situ (is that possible?) and the valve seats left alone, merely needing a light grinding in of the valves on refitting to ensure a good seal? If so, how much (length and width) needs to be machined from each guide?
Advice please.