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HZ 308 Rebuild Running Sluggish

Gday need help from the experts because I am not one.
I have a HZ 308 Prem which has been rebuilt and the following changes have been made to the stock motor. Electronic ignition, changed to unleaded, original factory aircon installed and new cam put in apparently for greater power because of unleaded (sorry not sure what cam but a bit tinny at the low rev end)
The car seems to be running so sluggish and crap and just doesn't sound right. There also seems to be a stronger than usual fuel smell from exhaust.
I checked the timing for the first time since getting the car back and it seems to be about 16-17 degrees advance (btdc). There were no more marks left on the advance side to accurately measure. Is this right....should it be this much? Or if it is sluggish does it need more which I thought would have been too much. Also my spark plug gaps are at about 1.35mm. Is this ok and does this greatly affect timing and would I need to change standard heat range plugs after all the changes (The original factory spec says 12 degrees at 1350rpm and plug gaps .08mm)
Any help would be greatly appreciated.

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Comments

Plug gaps don't sound right, but I'm no expert.

What I can add though is that sometimes the timing marks on the harmonic balance can move. The rubber deteriorates over time, and the outer part of the balance moves. Which might explain the unusual initial position.

Cheers, Steve.

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Steve so even with electronic ignition or performance like cam do you think the initial setting is a bit too much? Do you kow what it should be more like?
Any ideas about the plug gaps? Because of the electronic ignition should it still be more than the normal old points setting? (.08mm)

Cheers

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I'd take the points back to .08, and see how you go. Won't take long, and if it doesn't change anything, you can always change them back.

Timing will always be different depending on the cam profile, and if it's been dialed in properly. So it could have been spot on. Check out Reapers work guide in the gallery on tuning.

Cheers, Steve

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It sounds like your plug gaps are too big. I run my 308 with electronic ignition with 0.8mm plug gaps. I wouldn't reccommend over 1.0mm. As for timing mine is happiest at about 8 to 10 Deg BTDC initial. It does depend more on your total advance which should be about 32 to 34 deg.

Hope this helps.

Cheers

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Thanks D-Lux will give these specs a go.

By the way can you tell me what is the simplest piece of equipment to buy in order to check the engine rpm while fixing the timing. I have a timing light but obviously its impossible to know what the idle rpm is. Is there something easy to use and can be bought from any auto store.

Cheers
P

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Checkout Jaycar, http://www1.jaycar.c...

DickSmith also do a unit.

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