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Location:
Sydney
Registered:
May 2002
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ajustable cam gears
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Sun, 20 October 2002 13:50
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what gains can be had in paying with the camgears on a closer to stock engine??? how hard are they to get working correctly and set up right
ie my 1J
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Location:
Finland
Registered:
June 2002
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Re: ajustable cam gears
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Sun, 20 October 2002 16:00
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You need programmable engine management to benefit from adusted cam settings.
Even very light port 'n' polish headwork preferred too.
-A.
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Location:
North Sydney
Registered:
May 2002
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Re: ajustable cam gears
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Mon, 21 October 2002 12:34
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I'm hoping to gain about 10rwkw's with a cam timing adjustment on the exhaust side with about +3deg adjustment.
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Location:
Sydney, Australia
Registered:
August 2002
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Re: ajustable cam gears
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Tue, 22 October 2002 02:53
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My limited experience indicates that not much can be gained with stock engines by adjusting the cam timing, but you can move the torque peak around in the rev range by advancing or retarding both cams. So if you want more peak power you can move the torque peak higher in the RPM range, you can gain a little here at the expense of mid range torque.
Some minor gains are available by really accurately timing your cams as there is always some small error from a factory setup. i.e Finding TDC with dial guages etc.
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Location:
Sydney
Registered:
May 2002
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Re: ajustable cam gears
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Tue, 22 October 2002 10:09
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I run an adjustable gear on my exhaust cam. As Will states, it allows you to move the torque curve around a bit. We got up to 6rwkw on it but sacrificed a little to bump the torque curve up and left the gain at 3rwkw.
Don't know about a stock engine though - I had exhaust, intake, fuelling and minor boost mods already.
HKS and JUN do adjustable cams at about the $300 each mark but I've also seem custom jobs using machined/modified stock gears.
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Location:
Peakhurst, Sydney
Registered:
May 2002
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Re: ajustable cam gears
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Tue, 22 October 2002 12:06
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What I have heard about playing with cams (esp replacing the cams for longer duration ones) is that during the course of engine modification, it is generally about the last thing that you would do after everything else, because a) high expense b) minimal gains c) more gains to be had from an engine with all the other mods done first anyway...although I don't know much about just changing the cam timing. SUPRAGTE, I'd be very interested to hear your results both power-wise and driveability.
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Location:
North Sydney
Registered:
May 2002
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Re: ajustable cam gears
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Thu, 24 October 2002 12:52
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Ill keep you guys posted with the results.
Also the latest microtech which im running i can choose the exact point at which the injectors fire within the 360 degree crankshaft revolution which will hopefully take even more advantage of the cam gear adjustments.
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Location:
Brisbane / Gold Coast
Registered:
May 2002
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Re: ajustable cam gears
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Thu, 24 October 2002 13:14
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Sequential injection doesn't do anything to improve the power of the engine, only improve the emissions and fuel economy.
(From the guys at Motec)
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Location:
Sydney, Australia
Registered:
August 2002
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Re: ajustable cam gears
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Fri, 25 October 2002 00:31
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and improved idle quality. (From MoTeC's competitor  )
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Location:
North Sydney
Registered:
May 2002
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Re: ajustable cam gears
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Sat, 26 October 2002 09:06
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But with the adjustment of the cam timming if i then align the injector timing to take advantage of the altered intake valve opening there would be some gains.
More thorough cylinder filling hopefully and a resulted increase in power.
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Location:
Sydney, Australia
Registered:
August 2002
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Re: ajustable cam gears
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Sat, 26 October 2002 23:04
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But don't forget that as revs go up, the window for correct injection timing gets narrower over time (stays the same as an angle) while your injection times are getting larger. Ultimately, as your injectors approach 80% duty at max power for example, your injector is open for 80% of 720 degrees anyway which makes any advantage of correctly timing the fuel pulse negligable compared to your A/F, ignition timing etc.
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Location:
gold coast
Registered:
May 2002
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Re: ajustable cam gears
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Sun, 27 October 2002 05:39
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I ordered one for my engine(1JTT) last night. It will be here on friday, i'll tell you how well made it is.
It costs $230.
I want to improve the midrange torque.
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