Does my cam look worn? Should I change it?
Discussion
TVR Beaver said:
if its still in you'll not get a micrometer around them.. you'll need a DTI to measure lift (that has more travel than the lobe )... I think screw fix sell them quite cheap.. also a base / holder of some kind 
I could roughly measure the height of each lobe from the shaft using the end of the micrometer, then compare with the next lobe. Edited by TVR Beaver on Monday 4th November 15:32
zed4 said:
I could roughly measure the height of each lobe from the shaft using the end of the micrometer, then compare with the next lobe.
its a rough cast shaft.. you need to be more accurate than that.. I take it you're talking a depth micrometer?...A DTI on the lobe or side of the lifter is your best bet.
TVR Beaver said:
zed4 said:
I could roughly measure the height of each lobe from the shaft using the end of the micrometer, then compare with the next lobe.
its a rough cast shaft.. you need to be more accurate than that.. I take it you're talking a depth micrometer?...A DTI on the lobe or side of the lifter is your best bet.
zed4 said:
I could roughly measure the height of each lobe from the shaft using the end of the micrometer, then compare with the next lobe.
I'll be honest, I just measured mine at the rockers.I know this isn't exactly best practice with hydraulic tappets, but when the cam came out my measurements correlated very closely to the wear on the lobes.
So as far as giving you a rough idea on wear, measuring lift at the rockers actually worked out Ok.
I paid more attention to how the figures varied than the measurements themselves, like a compression test your more looking for variation than a figure.
But with the inlet manifold off you're currently able to measure the wear properly, so all that's stopping you is a cheapo Chinese made DTI off Ebay that you could have by Wednesday/Thursday if you order it today.
Buy a gauge like this for £8.00 delivered.
http://www.ebay.co.uk/itm/401120-0-10MM-Precision-...
And a clamp like this for £11.00 delivered, (a magnetic clamp is better but it's not going to hold on an ally block)
http://www.ebay.co.uk/itm/Universal-Adjustable-Ind...
So for less than £20.00 you can find out if all this is just panic on your part, or you really do need a cam change.
If you do, in my opinion trailering it up to Rob is still a good option, if you really feel you can't tackle it yourself that is.
First things first though, you need to prove if the thing is actually worn or not.
Edited by ChimpOnGas on Monday 4th November 16:37
jojackson4 said:
Derick was after some work may be worth giving him a prod you may end up with nos as well
He's busy. I'm hoping the Southways price is reasonable as I’d prefer they did the job – (nudge nudge Rich if you’re reading this!) I’ve had a quote from another specialist which I’m happy with, but they’re a bit far from me. I’d rather not trailer it any further than an hour really.
Sorry to bring up an old thread but did you get your cam changed zed? And if so how bad was it when it came out?
The reason I ask is I've just took my valley gasket off and the cam lobes look ok but there is some discolouration and I read on RPI eng. that this is the first indication of wear
The reason I ask is I've just took my valley gasket off and the cam lobes look ok but there is some discolouration and I read on RPI eng. that this is the first indication of wear
Twistygit said:
Sorry to bring up an old thread but did you get your cam changed zed? And if so how bad was it when it came out?
The reason I ask is I've just took my valley gasket off and the cam lobes look ok but there is some discolouration and I read on RPI eng. that this is the first indication of wear
Hi,The reason I ask is I've just took my valley gasket off and the cam lobes look ok but there is some discolouration and I read on RPI eng. that this is the first indication of wear
Yes I did change the cam. It wasn't really that worn to be honest, but it was halfway apart anyway and I managed to get a very good deal on a new V8D MC1 cam which I couldn't turn down. I then trailered the car to Southways, they fitted the new cam and timing kit and then put it all back together again. For the money, it was worth doing seeing as it was most way apart anyway.
I'm really pleased I did it, the MC1 cam is great, it drives really smoothly now and it makes very good power. I find it a lot easier to drive slowly around town now.
I did a few bits whilst it was apart, changed the valley gasket was it was leaking, changed the waterpump, upgraded the trumpets and induction hoses.
I didn't actually get to see my old cam, I seem to remember Southways saying it was a bit worn, but not too bad. However, I did have a broken rocker, so it was a good job I had it apart.
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Good advice on cam choice here. An indication of worn cam is signs of concave dishing on the under side of the hydraulic tappets.
A debate here on MC1, Stealth, TVR power 885 (Taraka Piper?) cams, for good drivability with least shunting at low RPM.
Stealth said to be a good option by some?
Wish we all knew the depth and quality of case hardening on cams. Perhaps too much to ask the cam makers.
Good advice on cam choice here. An indication of worn cam is signs of concave dishing on the under side of the hydraulic tappets.
A debate here on MC1, Stealth, TVR power 885 (Taraka Piper?) cams, for good drivability with least shunting at low RPM.
Stealth said to be a good option by some?
Wish we all knew the depth and quality of case hardening on cams. Perhaps too much to ask the cam makers.
Edited by EGB on Wednesday 24th September 12:40
Plus one for V8 Developments..
My cam did not seem too bad 1 year back, but the old girl seemed tired.. After numerous conversations and photos with V8 developments… I decided to go for a drive, all the way from France to Robs place to replace my cam…
Rob and Ray great team, they worked flat out all day, When the cam was removed the first two lobes were worn, the new cam went in followers etc great care was taken to dial it in correctly with a DTI, the cleaned timing case and oil pump were checked, all my rocker gear was stripped, checked and rebuilt by Ray. My job was to supply endless cups of tea..
With the new cam the result was a complete change, the car was more drivable and pulled like a train. On the recommendation of Rob I have since changed the spark plugs to hotter rating (no track days for me), new dizzy cap and rotor arm and changed all the HT leads to MOROSO.. She runs so sweet now, thanks Rob and Ray..
My cam did not seem too bad 1 year back, but the old girl seemed tired.. After numerous conversations and photos with V8 developments… I decided to go for a drive, all the way from France to Robs place to replace my cam…
Rob and Ray great team, they worked flat out all day, When the cam was removed the first two lobes were worn, the new cam went in followers etc great care was taken to dial it in correctly with a DTI, the cleaned timing case and oil pump were checked, all my rocker gear was stripped, checked and rebuilt by Ray. My job was to supply endless cups of tea..
With the new cam the result was a complete change, the car was more drivable and pulled like a train. On the recommendation of Rob I have since changed the spark plugs to hotter rating (no track days for me), new dizzy cap and rotor arm and changed all the HT leads to MOROSO.. She runs so sweet now, thanks Rob and Ray..
EGB said:
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Good advice on cam choice here. An indication of worn cam is signs of concave dishing on the under side of the hydraulic tappets.
A debate here on MC1, Stealth, TVR power 885 (Taraka Piper?) cams, for good drivability with least shunting at low RPM.
Stealth said to be a good option by some?
Wish we all knew the depth and quality of case hardening on cams. Perhaps too much to ask the cam makers.
Mine doesn't shunt at all now. In fact, I can do 25mph in 5th if I can't be bothered to change down!Good advice on cam choice here. An indication of worn cam is signs of concave dishing on the under side of the hydraulic tappets.
A debate here on MC1, Stealth, TVR power 885 (Taraka Piper?) cams, for good drivability with least shunting at low RPM.
Stealth said to be a good option by some?
Wish we all knew the depth and quality of case hardening on cams. Perhaps too much to ask the cam makers.
Edited by EGB on Wednesday 24th September 12:40
Dave, you mentioned earlier that zinc content in an oil destroyed the catalysts? Have you got hard and fast technical evidence for this.
I don't wish to throw away my Penrite HPR15 full synthetic + best for zinc.
For longer life, Rover tappet and cam lobes were meant to be protected by zinc. Double valve springs in the 500s put extra strain on cam lobe to tappet interface. Thanks. Congratulations Z4. I'm still debating whether to have Stealth an 885, or the MC1 cam.
I don't wish to throw away my Penrite HPR15 full synthetic + best for zinc.
For longer life, Rover tappet and cam lobes were meant to be protected by zinc. Double valve springs in the 500s put extra strain on cam lobe to tappet interface. Thanks. Congratulations Z4. I'm still debating whether to have Stealth an 885, or the MC1 cam.
Edited by EGB on Wednesday 24th September 21:10
phazed said:
l6rth said:
I thought the only reason to have an mc1 was if you couldn't have a stealth? I'm not expert but I am intrested in your dilemma.
the Typhoon doesn't require fly cut pistons either.
OleVix said:
but the stealth does, that probably means it has higher lift and a bit longer duration than the mc1/typhoon? I want to get valve reliefs cut into my pistons, do you know how much is needed Peter, or might be easier to ring Rob
Rob will know or try direct, Andy at Chesman Engineering, they did mine.http://www.chesmanengineering.co.uk
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