Duplex chain

[tomlucke]

Hi folks
I've made a bit of a mistake fitting an ital engine to my traveller.
I got things running and noticed the timing chain was making a racket.
I had forgotten to remove the 2 bolts under the crank gear and replace with countersunk screws.
I'm going to replace the chain and rectify the bolts.
Three questions:
How do I countersink the holes? The engine is in the car and the front panel is on. I'm not sure how I can get a drill bit in to open them out as there is not much space?
Is it worth buying a full duplex kit or just the new chain and screws?
Do I need to modify the ital timing case any further (the breather canister has already been modified)

Thanks
Tom

[bmcecosse]

Did the Ital engine not come with the rubber tensioner chain system? If so - it's MUCH quieter in the long run than the duplex - which has no tensioner at all. Duplex is for strength - high lift cam and/or super high compression springs. And sure - it will be quiet initially because it's new - but that doesn't last for ever! However - if you persevere with the duplex, the holes are countersunk (unsurprisingly) with a countersink bit in a drill gun! If you can't get in - you will need to take the front plate off. If the chain is damaged then yes fit new - but sprockets etc will be fine.