Rover V8: Cam gallery blocked and upgrades

Rover V8: Cam gallery blocked and upgrades

Author
Discussion

IPAddis

Original Poster:

2,479 posts

291 months

Monday 4th November 2002
quotequote all
I was slightly suspect when my cam failed on the number 5 exhaust lobe instead of the usual number 8 exhaust when I had it changed 4500 miles ago.

It has been making quiet tapping noises again recently but I put those down to slightly dark oil (due to be replaced last Friday). A week ago, it started making LOUD tapping noises and I had it taken to V8 Developments for diagnosis.

They are now pretty sure that the cam oil gallery is blocked as both number 5 and number 6 cam lobes are now round again. This requires an engine out job to re-bore the cam gallery.

Have any other TVR owners experienced the same fault? It only did 25000 miles on the first cam so presumably the blockage could have been bad drilling of the gallery by TVR Power.

Are there any other upgrades (cross-bolting, etc) that are worth doing while it is having effectively a full engine-out rebuild.

On the plus side, V8 Developments reckon it's only (!) about 1300 quid to fix it and they will warranty the work. It's a shame it wasn't picked up when I spent 800 quid changing the cam 6 months ago but I guess there's no much you can do to test for these things.

Regards,

Ian A.
Griff 500 (in bits).

clint888

101 posts

265 months

Monday 4th November 2002
quotequote all
Yes--V8 can do a capacity increase up to 5.3 and you could try an ACT triple throttle plenum + carbon fibre trumpets + polished manifolds. I don't know if they also do a personal racetrack to go with all this

IPAddis

Original Poster:

2,479 posts

291 months

Tuesday 5th November 2002
quotequote all
Not sure I need the extra 0.3 litres. I've got enlarged inlet manifold, widened & flared trumpets and trumpet base but I haven't got the triple plenum job yet. That's an easy fit though so doesn't need to be done at the same time as the engine is out.

Is cross-bolting the block worth the effort?


clint888 said: Yes--V8 can do a capacity increase up to 5.3 and you could try an ACT triple throttle plenum + carbon fibre trumpets + polished manifolds. I don't know if they also do a personal racetrack to go with all this


wedg1e

26,891 posts

272 months

Wednesday 6th November 2002
quotequote all
Cross-bolting is only worth it if you DON'T have it done and the engine subsequently breaks ;-)

I can't work out what you're saying here: the camshaft oil gallery is blocked? As far as I recall (and I'm just looking at a lubrication diagram for the RV8) the oil pump feeds two galleries, one each side of the block. These drop down to feed the crank main bearings; the cam followers pick up from them and the cam journals also get fed from there. If you have a blockage causing the cam JOURNALS to wear then you're possibly also looking at crank main bearing wear. If it's just the cam LOBES, I can't see how blocking the gallery would cause this as there's plenty of oil running down from the top end to splash lube the cam. You'd expect the cam followers to go tits-up in good fashion though, with no oil feed.

I doubt that TVR Power drilled the oilways: that would have been done by the machine shop that preps the blocks from rough cast. There are quite a lot of machining operations on an engine block: line-boring the crank and cam journals, drilling the oilways, boring the cylinders, threading all the holes etc., some of which require more jigs and setting-up than a small-scale operation like TVRP would want to do.
Even then, it would have to be a major cock-up if an oilway was blocked at that stage.
The later V8 blocks have replaceable shells for the camshaft to run in; it's those that get bored (or perhaps reamed!) to suit new cam journals.

You can access the galleries that feed the cam followers with a simple top-end strip; you don't need to take the engine out.

Ian

IPAddis

Original Poster:

2,479 posts

291 months

Wednesday 6th November 2002
quotequote all
Hmm, thanks Ian. It's the hydraulic tappets that are not getting filled with oil, which obviously then destroy the cam lobes in a short space of time and taking out the rocker arms and two valves with them.

Where do the tappets get their oil feed from?

Ta,

Other Ian.

wedg1e

26,891 posts

272 months

Wednesday 6th November 2002
quotequote all
Ian:
Mail me direct so I get your email address and I'll send you the V8 lubrication diagram. If you don't get an immediate reply, it's because I'm off to Birmingham tonight, will be back (I hope!) Thurs evening so can sort it then if not sooner.

Ian
tvr390se@ntlworld.com