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Old 05-01-2004 | 09:25 AM
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orangbaligila
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Joined: Feb 2004
Posts: 368
From: Bali, Indonesia
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this is how I run-in my CVX about 3 years ago,...

heat cycling:

with the setup you mentioned before (turn the LSN 90degs in when difficult to start):

7 mins running (leave glow-starter for 30 secs to help the engine gain some temp), then stop and cool down (car on a stand, wheel is free, set the idle so the wheel are moving only slightly,... no movement is better), after stopping the engine, make sure the piston is not at top dead center (TDC) by turning the flywheel,... the "tight" position is TDC,... move further till you pass it, then stop the piston (approximately in between the lowest position and TDC) I did heat cycling for 2 tanks

Constant idle:

Lean HSN 1/8 turns, fill tank, start engine and leave it idling for 3 tanks wheel still off-the ground, keep filling), try to set the idle as constant as possible without leaning the engine,... after the third tank almost finished,.. stop the engine (by covering the exhaust outlet) and let cool (don't forget to align the piston out of TDC)

Slow run:

Lean HSN by 1/8 turns every each tank for this run.
try to get the car moving (wheel on the ground),.. short burst of throttle (partial, max 25%), if difficult to move or dies,... lean the LSN by 45 degs, I did 2 tanks on this,.. let cool and align piston


Mid run:

same as above, but you can apply 50% throttlr, remember, short bursts only,... don't let the engine stay on the same rpm range for a long time. did thid for another 2-3 tanks (non-stop), let cool and align piston

Now, after it all cools down,.. remove the plug,... and turn the flywheel,... if you still feel the engine tight at TDC, repeat mid-run procedure,... after installing plug of course


if not very tight (some tightness is good,.. a lot is not good),... you can start to tune it for top performance, start from HSN, then LSN,... don't hold it at high rpm for a long time with the wheels off the ground (I know it's cool,... but overheating may occur,.. and it's bad...) don't get it as maximum as possible yet,... try to run it up and down the straight,... if throttle response feel sluggish,... lean LSN bit by bit,.... if it still revs after you release the throttle,.. LSN might be too lean already,....

as a guide, the HSN setting is normally around the 1.5 turns out +/- LSN is up to your liking but don't be too lean,....

a healthy engine should spurt out thick white-blue smoke on rev,... if only white mist,... probably too lean,... if fuel spitting out (or your eyes becomes watery),... that's rich,...

I hope this helped
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