Sorry to hear of your woes, Greenman. I’m no expert with RV8s. Out of interest, what car is it in? Have you tried the Engines forum on PistonHeads?

My pet V8 is an AJP which had a top end rebuild recently after cracking a valve spring (luckily 2 springs per valve so it didn’t drop). To pay my wallet back for its kindness, it’s now lunched it’s starter too. Oh what joy!

Hope it helps, chap.

I just tried “rover v8” and “rv8” to seach the engines forum and got 5 and 6 pages of threads respectively.

Alternatively, just create a login for yourself on PH if you haven’t already got one and post a new thread with your specific question. The amount of knowledge & peoples’ willingness to help on PH really is quite staggering.

Good luck.

What are the symptoms of the problem on your V8 … I know a bit about them

Its not easy diagnosing a car problem without actually seeing the thing, but if you suspect its firing on only 4 cylinder, a couple of points to look into is, One, if it’s carb problem, it will knock off two cylinders on each bank, not 4 on one bank only! …. If you suspect the inlet manifold, it will pi** oil out due to there being a slight pressure in the crank (its there to stop oil seal deformities, and a couple of other reasons not worth going into) the design of the inlet manifold is crap …..

The flame trap on the rocker cover is prone to blocking up … it should have a wire type filter in it, if you suspect this, then gouge out the wire and refit and test, if it is, that then replace, this is a serviceable item anyhow! … some depending on chassis number had an over rev limiter on the ignition, this knocks off one bank! … I’ve come across them going wrong before, if you can substitute a known good distributor then try that, it will save you lay out cash on something that might be ok.

A common fault on the Range Rover V8 engine, which incidentally, might not be fitted to your car? (has it got the original engine fitted, it might have had a swap in its life, some have been exchange with the SD1/SD2 motor … the compression ration is stamped on the block, RR V8 compressions are lower! … anyhow a common fault on the RR V8’s was that they flattened the cam lobes, this was prominent on the back cylinders, this cause sluggishness and a course engine. The Hydraulic tappets were not pressurised enough and therefore the values never opened enough and the duration was far too shorts.

Run the engine and start systematically checking it, start from the beginning again, don’t jump in!

Get engine to normal temp, is it running ok, Y/N? … If not check CO levels, check spark plug colours and comparable condition. Check cylinder compressions, all should be within 15lbs of each other. When does the problem occur? … static at idle? … under load? Etc … when you took off the rocker covers, was there a noticeable high build up of carbon? … if so suspect follower malfunction, this will show up on a compression test! … do you know someone that has a cylinder leak tester? … if so get a test done … are there any abnormal engine noises? … Rocker have hardened inserts that rest upon the push rods when operating the valves, these at times become loose (more noticeable on idle)

As mentioned it’s not so easy to diagnosis a problem from afar … I worked at Land Rover/Rover for quite some years and even with the vehicle in front of you it at times can be baffling, that said the vast majority of the time it was something quite straight forward.

Good luck and don’t jump ahead of yourself, it can be a costly business not looking into the basics