Duplex chain alignment issues

[Gadgetman]

I’m just installing a duplex chain and gear set on my 1600 vitesse during the engine re-build. 

The new cam gear is biased / dished  one way by 170 thou. 

When im trying to time the cam this offset eliminates the ability to turn the cam gear over to get the cam timing adjustment I need as it throws out the chain alignment 

Anyone got any ideas???

i can’t turn the crank gear around as it is machined our on one end to fit snugly against the crankshaft nose. 

 

[JohnD]

Shims behind the crank pinion will bring it into line.

John

[Gadgetman]

I’d need a lot of shims as it’s .170 out of alignment!!

[Pete Lewis]

The joys of aftermarket supposed upgrades , question , why do you want a duplex..???

And have you asked the supplier how this is designed to work as  its not suited to the engine  if you cant turn the gear over I guess you are stuck with  only 1/2 tooth incremental adjustment not  1/4toorh of the turn over single sprocket ?

Pete

[rogerguzzi]

Hello

        Just as all the TR6,s

You just have to get the nearest you can!

A bit advanced gives either more torque or is it top end and late is opposite!

Roger

[JohnD]

56 minutes ago, Gadgetman said:

I’d need a lot of shims as it’s .170 out of alignment!!

I just love people who ask advice, and then give reasons why good responses won't work.

A thick shim is a thin washer - what's the difference?

OR, and unless as Pete suggests you send it back, a machinist could soon take 170 thou off the back of the sprocket on their lathe.

John

[Anglefire]

1 hour ago, rogerguzzi said:

Hello

        Just as all the TR6,s

You just have to get the nearest you can!

A bit advanced gives either more torque or is it top end and late is opposite!

Roger

Mines slightly out - and it's got more grunt lower down, which is fine for my style of driving.

[Gadgetman]

Sorted 

I pulled the cam out to find out what was up and checked which part number it was, I’d fitted my new 306785 by mistake instead of my new old stock 308778, no wonder the timing looked odd! 18/58 when it should have been 25/65 !!!

re timed with the 308778 and all is spot on, equal lift at overlap / tdc and correct lift!...

thanks for the advice though.