Hi again,
Been a bit preoccupied lately , Fitting out a camper truck and doing a engine build for a triumph stag. Any Whoo Ive had the turbo motor running.
But no matter what I did I could not get it to play nice. Rough idle , no power, wacky air fuel ratios, low low manifold vac at idle. As well as a stuck injector that filled the motor with fuel and caused a hydraulic lock when cranking.
So I pulled the motor and striped it down to bare bones to check for damage.
Fortunately nothing other than a bit of carbon from overfuling.
So I bought a degree wheel and a dial gauge so I could check the cam timing (remembering that the engine is built from a parts bin)
Looked up the cam specs in a vp/vr manual I had and guess what. It states intake duration including ramps starts at 26 deg BTDC and continues for 314 crank deg. MY cam from a supposed stock engine starts 50 deg BTDC and continues for 325deg.
I couldant believe my eyes. So I measured the duration in crank deg at 50 thow lift and came up with a duration of 295 deg.
This cant be right so I double and triple checked and then checked again.
Blown away I had a look at the crow cams data for their cams and even the wildest ones they sell don't have 295 deg of duration at 50 thow lift.
So what to dooo.
Ordered a new standard cam and timing set.
I am surprised the beast even ran. Serves me right for assuming a second hand cam from a dodgy mate would be as described (probably not his fault ) It is hard to tell what a cam is just by eye.
So when the bits get in Ill bang it back together and have another hit.
Can anyone speculate on where such a wild cam might have come from ,It had a wild idle and it must have been carbd not efi.
If it was custom efi it would have cost a heep to get tuned, or maby it proved too lumpy and was swaped out quickly ,which would explain why it looked so good.
moor to come soon.
Cheers Nath
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