Adjustable cam sprocket

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geminilover3236
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Adjustable cam sprocket

Post by geminilover3236 »

Found this while stripping an engine today. Has 3 settings marked 0, A, R

Guessing the A = Advanced, R = Retarded and 0 is neutral (standard)

Anyone come across this before, not sure by how much it's advanced or retarded but going to have a play at some point.

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GEMWRC
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Post by GEMWRC »

And a Kangaroo stamp . What brand had that ?
sly380
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Post by sly380 »

That there is a genuine quantas cam sprocket
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Gigantor928
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Post by Gigantor928 »

I think if you advanced your cam gear that much on the cam to advance or retard it, according to those holes, you'd have an engine that wouldn't run... If you connect your cam gear 1 tooth out it doesn't run properly. The cam gears we use in our race cars adjust by a few millimetres each way to get results...

Not sure about that...

Interesting though.
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LOK15
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Post by LOK15 »

hahahaha those holes dont quite work like that jason.. You set your cam to TDC and move the bottom end slightly till the hole lines up , effectively setting the cam timing advanced or retarded by however many degrees they have allowed.

think i have a few of those floating around at home.
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Gigantor928
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Post by Gigantor928 »

Oh right... now I actually think about it, I see what you mean. Thanks Lok :D
tobytj
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Post by tobytj »

An experienced engine builder gave me a tip on getting the cam timing right on a modified cam that has to be dialed in - but have not been game to try it.

Evidently you remove the locating pin and install the sprocket 180 degrees out so the the locating hole pin holes are also 180 degrees out. You use the cam shaft bolt tightness only to make adjustments to get cam dialed then remove the cam and sprocket in one piece and drill a hole in the cam for the locating pin.

Anyone tried this?
TURGEM
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Post by TURGEM »

was just wondering. would anyone know how many degrees you would get if you changed the cam by 1 tooth

Eg. 10 degrees every tooth

I just want an adjustable one for a single row chain... Surely sum1 can make a decent and sell it, I ask engineers and they are not interested. :(
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Turbocoupe75
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Post by Turbocoupe75 »

I made an adjustable cam gear for my gem and dialed it in correctly, with a decked block and head the cam gear was more than 1 tooth out of position.


viewtopic.php?t=24089&highlight=


To be honest it's not worth making one coz a custom one like mine would cost around $ 250 to make up for an engineering shop, personally I would look at getting a few dowel holes made up on a mill with a dividing head and an experianced machinist to measure them.
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moley
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Post by moley »

I have the same cam gear in mine, wade custom turbo grind 1.6 head 2.0 block and it dialled standard. The gear only allows +1 or -1 degrees
geminilover3236
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Post by geminilover3236 »

If you draw a line from the centre of the cam sprocket to the outside and note where it cuts the tooth. It looks roughly like it advances or retard half a tooth.
Encyclopedia Ronnie
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Post by Encyclopedia Ronnie »

i like how you have done yours but i think i would probably do it a lil bit differently, im gonna test it out on a single row and if it works im gonna do my double row rollmaster, when i do it ill get some pics up
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TURGEM
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Post by TURGEM »

Guess I better read up on how to dial a cam in and give it a shot, I can gurantee mine will need dialing being so large...

Hence why I was curious to know how many degrees you get by moving the cam by one tooth... If its close I miget way with just moving one tooth instead of going all out on a vernier gear....

In asia area the cam gears are available but I think you have to be a proper racer with papers (public cannot purchase them) sucks balls
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