Rover P5b engine conversion

If you have a Rover P5B V8 model like I do, you’ll probably love the car, but it could use some more power. The original engine of the P5B is of the 3500 cc variety. The nice thing when it was first released was that it had a higher compression ratio than some of the later engines, but because the heads had smaller inlet and outlet valves, it still limited power a bit. The other con was the problem that LED fuel was not available so you have to keep adding lead additives to the fuel which many P5 owners know is a bit annoying since you are always at the gas station with a such a big engine

My first trick was to replace the cylinder heads with cylinder heads from the Rover SD1 which with the larger valves and unleaded valve stems saved me the trouble of putting the fuel additive each time, but I really didn’t notice much extra power. The Rover P5B is a very heavy car anyway and I suppose you shouldn’t drive it fast, but I was hoping for a small change in performance. I then added a Weber carb and changed the ignition to a Lumenition electronic ignition system to get rid of the old point system. This made a bit of a difference, but the performance was not what I would call a start.

So I decided to rummage through my pockets, steal the piggy bank and opt to install the 4.6-litre engine from the latest Range Rovers. Now this engine is actually the same stock block as the 3.5 ltr from the Rover P5, so it’s actually almost a direct swap. If you keep the stock distributor from the P5, you should keep the same front engine cover because the oil pump teeth are different for each model. Other than that, everything is going very well. The engine mounts line up and all the exhaust manifolds are back together like the old one. If you’re trying to keep your Rover looking original, you can even use the original rocker covers so even the insurance man can’t tell the difference. Until he drove it, of course.

How do you drive? Well, between the two engines it’s like night and day. You’ll be grinning from ear to ear for days afterward. So if you have a few spare bobs and need your Rover P5 to pick up its heels and go. Your only option has to be the 4.6Ltr V8.