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
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