Timing/distribution chain

J

Jens

Member
Does anyone know which timing chain is most stretch (elongation) resistant: the genuine (Land) Rover 3.5 ltr. V8 timing chain or the Cloyes TRUE roller chain ?
and
what is the benefit (if any) of a (Cloyes) roller chain compared with the genuine (Land) Rover 3.5 ltr. V8 timing chain ?
Pls. your suggestions.
 
Hi Jens,

The factory timing chain sets are of the Morse type, running on a nylon toothed gear wheel. These stretch very rapidly, and the nylon teeth will eventually break off.
Any true roller chain set will be vastly superior, be it Cloyes, J & P Performance, or another well regarded brand.

If you are going to replace it, then a true roller set is by far the best option.

Ron.
 
I replaced my standard one after it had completed 60000 miles. it was stretched but how many miles do you intend doing.
 
I have the experience that a Cloyes Street true roller is completely elongated after 3000 km about 2000 miles even more than a genuine chain after 300.000 km.
I can send you a clip of this elongated Cloyes chain to your personal email adres if requested because the forum does not upload VLC media files.
 
Really aren't Cloyes chains pre-stretched? I thought they had a superb reputation in US classic car and rodders circles? Certainly many of the Rover engine specialist in the UK recommend them.

The original Rover item is unlikely to give very accurate timing much after 50,000 miles.
 
Oh Dear . I replaced mine a year or two back . Only because I took the front cover off to upgrade the oil pump. The chain was 40 odd years old and stretched. So I would say I got a good run out of the original factory jobbie.
 
GRTV8 said:
Oh Dear . I replaced mine a year or two back . Only because I took the front cover off to upgrade the oil pump. The chain was 40 odd years old and stretched. So I would say I got a good run out of the original factory jobbie.
Click to expand...

You sure did Gerald ! Were many of the nylon teeth missing? Of course, with a stretched timing chain comes retarded camshaft timing, and whilst that means a reduction in low end power, it also means an increase in top end power!

Ron.
 
I recently acquired a 4.6 that has had a rebuild. I completely torn it down to inspect it. The timing set was a new double roller set from J&P, available in the UK from RPI. The slack on the chain was the worst I've seen on any old used set.
I was unable to get any sense out of either RPI or J&P in Australia as to why this was so, the block has not been line bored.
I contacted Turner Engineering who rebuilt the engine in the past and the very helpful guy there said that they only fit factory timing chain kits on their engines.
I bought a factory set for it with steel gears as they don't come with a plastic gear anymore and the chain is tight.
So moral of the story is - 'upgraded shiny' is not always better.
I do not have any concerns regarding longevity, the car is a limited mileage classic.
 
Well, I'm really worried now, this seem to go against everything I've read over the last decades. I bought the Cloyes true roller - the full one, not the "street" model as I have colleagues who go on business to the US and this one is usually available off the shelf. I'm finding this all very strange RPI, V8 tuner and any number of Land Rover specialists must have seen 1000s or more of these. Not only that, the self same chains are used in practically all US V8s and the reputation from 10s or 100s of 1000s of application is also fairly unanimously positive. So it'd be interesting to get to the bottom of this.

Perhaps the issue is with an all steel set-up, you really need those two holes to allow oil to drain back over the chain? The nylon gears I assume are gentler on the chain and (perhaps) to a degree "self lubricate".

All I know is my nylon one has done 100,000 miles and is completely finished.
 
I have a J & P Performance chain set on my 4.6, now having covered 154,000 miles. The last time I removed my mechanical fuel pump, I could see the double rows of the nice shiny silver chain. I gave it a poke with a screw driver, there was a degree of movement, but I cannot say it that was excessive or not. My Rover's original engine ran for just over 203,000 miles (327,000km), and upon inspection, all but two nylon teeth were missing. The chain was incredibly loose, with the gent who built my 4.6 saying that it was the worst he had ever seen in over 30 years of working on Rovers and Range Rovers.

Ron.
 
SydneyRoverP6B said:
You sure did Gerald ! Were many of the nylon teeth missing? Of course, with a stretched timing chain comes retarded camshaft timing, and whilst that means a reduction in low end power, it also means an increase in top end power!

Ron.
Click to expand...
Hi Ron. The teeth were all accounted for - just the chain stretched to Africa.
Certainly lifted her skirts after the new unit went in.
 
Reviving this slightly as I'm at the point where I'm buying new components to rebuild my 4.6.
Cobraboy, was your 4.6 Gems, Thor, or converted to an early type front cover?
I've been researching options of fitting vernier timing sets to blocks with later front covers (when not using the cam sensor). As far as I gather many of the double roller chain sets foul on the covers and require some modification of the aluminium inner casting. Apparently the Kent sprocket clears with the 4.6 horseshoe cam retaining plate, along with J&P and cloyes, with minor modification necessary in some combinations.
It's interesting that someone got Turner to rebuild an engine and then they or somebody else replaced the standard timing set which Turner would have fitted..unless they used to fit the J&P and this is one of the ones gone bad? Perhaps the chain was the wrong part? Or used?
Was there any evidence of rubbing? That could have lead to premature wear
As far as expensive and shiny, yeah they surely need to perform better or money could go on other areas of a rebuild. Standard Gems chain set is very cheap in comparison
The key use of an adjustable set on a rebuild of course, and why I want one, is to achieve optimal cam timing
Jim
 
Well, part way through my cam fit. The nylon gear looks like new BUT the standard chain is flapping around more than 5 degrees of cam timing. When it's all back together we'll see how she runs.

Even the removed cam looks fairly newish. All very strange.
 
How were the lifters Peter?
Since stripping my 4.6 I found a couple of mine were very noticeably domed, plus the rearmost cam lobe was severely rounded. Bearings look good so far, as do the cylinder bores. No obvious head gasket breaches either. So far the seller's description from a few years back is proving to be an honest one. Nevertheless it's getting the flanged liner treatment.
Jim
 
Lifters looked pretty good. I'll put some pictures up. The engine has 160,000km or 100,000miles. I'm suspecting these are not original parts.

No idea of the condition only that from the oil change records, the car's done 10,000km since 1993.
 
corazon said:
Reviving this slightly as I'm at the point where I'm buying new components to rebuild my 4.6.
Cobraboy, was your 4.6 Gems, Thor, or converted to an early type front cover?
I've been researching options of fitting vernier timing sets to blocks with later front covers (when not using the cam sensor). As far as I gather many of the double roller chain sets foul on the covers and require some modification of the aluminium inner casting. Apparently the Kent sprocket clears with the 4.6 horseshoe cam retaining plate, along with J&P and cloyes, with minor modification necessary in some combinations.
It's interesting that someone got Turner to rebuild an engine and then they or somebody else replaced the standard timing set which Turner would have fitted..unless they used to fit the J&P and this is one of the ones gone bad? Perhaps the chain was the wrong part? Or used?
Was there any evidence of rubbing? That could have lead to premature wear
As far as expensive and shiny, yeah they surely need to perform better or money could go on other areas of a rebuild. Standard Gems chain set is very cheap in comparison
The key use of an adjustable set on a rebuild of course, and why I want one, is to achieve optimal cam timing
Jim
Click to expand...
Jim
The engine I bought was a collection of parts that I spent several hours picking through to try to make out what was there.
The block is a 4.6 46D --------- HPR so is probably a GEMS block. This was reconditioned by Turner engineering in the past and Turner were kind enough to look up the job sheet and tell me about it. It has their top hat liners with seals at the bottom. Turner did the work a while ago, so the engine has had a life since.
The heads are quite nicely worked SD1 heads, but not from the Turner build. The front cover is SD1, but I got the rare intermediate cover as well. The cam is fast road.
A Holley and Offy came with it, along with Offy rocker covers and a dist.
I have since calculated the CR and have since had the heads skimmed to give 10.0 :1 CR, and have carefully set up preload and spring heights and all clearances.
I am undecided as to whether to fit the Holley or jet up the SU's.
As I said the timing set was J&P double roller, which was so slack. The sprockets are unmarked as is the insides of the chain so I believe them to be new. I have read posts on the net about slack J&P sets.
I spoke with J&P and RPI neither seemed to want to give much info away.
Turner on the other hand could not have been more helpful and told me that they only ever fit stock timing chain sets, I bought a new stock set and it is tight confirming that the block has not been line bored.
The SD1 front cover seemed to go over the J&P set OK . I will run the SD1 cover as I feel familiar with it despite the intermediate cover having the better oil pump. The car is not a daily driver so I don't see a problem.
I took a gamble on the purchase and have found an issue upon inspection since, time will tell if I have got over it or not.
Mark
 
Thanks for the info Mark,
You can't fault Turner, they seem very good in every respect. They are also very close to me geographically which makes them the obvious choice to do my liners. However with the VAT they charge £1600 for the work which is just not possible for me currently. I'm looking into someone else doing the machine work with their Darton O ring liners.
I'll post some photos of my 4.6 dismantling discoveries in my project build thread
Jim
 
Just so it's all in one place as part of a discussion, here is the bad lifter and cam lobe from my 4.6

image.jpeg image.jpeg image.jpeg

Jim
 
Yup, not much in the way of lift on that...

My removed lifters look like your "good" one 3rd from the left in the first picture. TBH all of yours are worn, the "bad" one merely being worse.
 
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