CDI box from www.amrracing.com
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Joined: Oct 2006
Posts: 3,106
From: Misawa Japan
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Same thing, just worded differently. Just like some ignition systems have vaccum advance or electriconic through means of a TPS. CPS (Crank Positoning Sensor) is the most important for base timing. The effect is to advance the spark to get more power out of the fuel for a short amount of time.
As for the 09' KLX. I think Kawi did not install one for the 09's.
As for the 09' KLX. I think Kawi did not install one for the 09's.
You are corrent on the 09 (no TPS).
As far as advancing the timing goes, the school of thought for low octane fuels -correct me if I'm wrong- would be to have some sort of knock sensor that retards the timing to avoid heat damage to the cylinder. That's why associating the TPS with low or high octane rated fuel doesn't make any sense to me....even if you're only talking about transients.
I completely agree with the 'vacuum advance' analogy though. Regardless of octane, I'd say it's there for that very function.
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Joined: May 2007
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From: Oklahoma City, OK
You are corrent on the 09 (no TPS).
As far as advancing the timing goes, the school of thought for low octane fuels -correct me if I'm wrong- would be to have some sort of knock sensor that retards the timing to avoid heat damage to the cylinder. That's why associating the TPS with low or high octane rated fuel doesn't make any sense to me....even if you're only talking about transients.
I completely agree with the 'vacuum advance' analogy though. Regardless of octane, I'd say it's there for that very function.
As far as advancing the timing goes, the school of thought for low octane fuels -correct me if I'm wrong- would be to have some sort of knock sensor that retards the timing to avoid heat damage to the cylinder. That's why associating the TPS with low or high octane rated fuel doesn't make any sense to me....even if you're only talking about transients.
I completely agree with the 'vacuum advance' analogy though. Regardless of octane, I'd say it's there for that very function.
Back on target. If we do get an aftermarket CDI. It would be a great improvement. Especially if its programble. We would be able to surpass the 35*BTC that takes hold at 5k rpms and help increase the top-end performance. It would be even better if it includes an progam on the switch, so just flip a switch and go from stock timing to power.
Last edited by LearjetMinako; Mar 7, 2009 at 01:40 PM.
Senior Member
Joined: Oct 2006
Posts: 3,106
From: Misawa Japan
1st Gear Member
True. Just as there is a spark advance, theres also spark retarding (knock sensor). Also, not all vehicles come equiped with a knock sensor. The analolgy for higher octane fuel is because of the more advance base spark timing. Hence the reason why some vehicles say to fill with premium fuel only. If you can lower the base timing and only advance it when needed, you can run on a lower octane.
Back on target. If we do get an aftermarket CDI for 06/07. It would be a great improvement. Especially if its programble. We would be able to surpass the 35*BTC that takes hold at 5k rpms and help increase the top-end performance. It would be even better if it includes an progam on the switch, so just flip a switch and go from stock timing to power.
Back on target. If we do get an aftermarket CDI for 06/07. It would be a great improvement. Especially if its programble. We would be able to surpass the 35*BTC that takes hold at 5k rpms and help increase the top-end performance. It would be even better if it includes an progam on the switch, so just flip a switch and go from stock timing to power.
I'll say one last thing about 'vacuum advances' and say no more. The vacuum advance was never designed with lower/higher octane fuels in mind...neither was the TPS. The vacuum advance improved throttle response, regardless of fuel. The TPS was designed for the same thing, but is pretty much a gimmick.
If you want to talk about spill-over effects, you are reaching, but OK.
Last edited by tremor38; Mar 8, 2009 at 12:33 AM.
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Joined: Oct 2006
Posts: 3,106
From: Misawa Japan
1st Gear Member
HEY, it's a probably a long time till the CDI gets to the production phase, so I'm just giving the thread some filler material.
Say thank you!
