im about to convert my turbo to the earlier set up so im using the earlier cam wheels cleaned them with wire brush and saw what looks like a hair line crack going all around the cam wheel one wheel is more obvious than the other is it possible it could be a hair line crack or more likely the mould of the metal or maybe a joint mark, are these solid structure wheels.
would someone please take a close looki at there valver or earlyturbo you need to look at the cam wheel on the inner edge just below the teeth.
please some one have a look to put my mind at peace as the rest of the kit is costing 250 pointless if the cam wheel is knackered water poump 40 quid cam belt 21 both rollers 156 quid lower sprocket 42 quid.
does that sound about right.
Sorry if I have misunderstood what you are trying to do, but if you are only wanting to convert from the plastic idlers to metal ones it would be far cheaper AND easier to buy replacement sleeves (metal) and bearings etc from SBD Motorsport, I recently looked into this and below is an extract from the Email they sent me in reply:-
There are two types of cam belt idler fitted to the C20LET. The earlier engine up to approx. 92 had steel idlers, one slotted adjustable type and one fixed lower type. After 93 they fitted an auto tensioner and two plastic idlers. If your engine is of this type the components cost as follows:
Inner bearing x 2 £19.60 +VAT
Idler sleeve £23.20 +VAT
Idler sleeve £23.20 +VAT
Circlips x 2 £1.96 +VAT
Total price £79.85 not including postage and packing.
The above converts the plastic idler wheels to metal, alot simpler and cheaper than they way I think you are going about it.
ILL HAVE TO BUY NEW BWCAUSE THERE IS NO POINT PUTTING IN OLD METAL ROLLERS I HAVE THE CAM WHEELS BUT SEEN A HAIR LINE CRACK LOOKS MORE LIKELY TO BE THE WAY THE METAL JOINS, HAVE A LOWER SPROCKET BUT IS RUSTY AND HAS A LITTLE INDENTATION ON ONE OF THE TEETH A LITTLE PARANOID ABOUT USING THIS CAMBELT AND WATER PUMP WILL HAVE TO BE NEW.
autotensioner & two idlers (later layout), square tooth profile
manual tensioner & one idler (early layout), round tooth profile
akaik, the latter setup never came with anything but metal rollers, whereas the former intially came with GF50 plastic ones.
The fact you say you need to change cam sprockets means that you are changing from the late to early type yes ?
If so, you will need a new backplate, as already stated - an those rollers you intend to buy new may not come with the requisite standoffs or bolts - plus there is another piece you'll need for the cambelt cover fitment, but you might already have some of these smaller bits from the old layout.
And what about the alternator and PAS pump drives ? - you'll have to change these, not to mention the whole PAS pump and it's bracket - the early layout uses a double V groove pulley which you'll also need.
i have back plate but i dont know which part you are referring to with regards to the cam cover at the moment the engine has the polastic rollers ie later cav turbo kreg i will need the round tooth set up.
there are 3 studs that stick out of the block, one to the left of the crank sprocket, one above the front engine mount, and one between the cam sprockets. Gary is on about these when he refers to the cambelt cover. this is what the cover is fixed to, and you need the correct rubber spacers and the 10mm bolts to hold the cover to the studs also.
you need the studs yeah, of course if the rubbers are the same re-use yours. Ijust dont know if the studs are in teh same place on the two different engines. in relation to the wholes in the back plate.