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cammmy

Green Dot Pulleys for GT3

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Hi Guys

 

Just wondering how the green dot pulleys work with the GT3?

 

On a 2.2 you swap one cam pulley for the oil pump pulley and buy one green dot? The service manual seems to indicate that the 2.0 has a green dot on it already though (on the inlet)? Does this mean I need to buy one GT3 specific green dot for the exhaust? I'm guessing if the oil pump did have a green dot on it but it was for a 2.2, it wouldn't be suitable?

 

Ta

Cam

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Just had a chat with someone at PNM, apparently the green dot is on the exhaust pulley and it's the crank pulley that's 2.0L specific, not the cam pulleys. So If there is a green dot on the oil pump, I should be able to just swap it to the inlet?

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Anyone know if the GT3 also has the green dot on the oil pump? The car doesn't live at my flat so can't easily check before ordering my service bits

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according to the parts manual the GT3 has the green dot on the oil pump and on the intake, so you should be able to move the green dot pulley to the exhaust cam, and the exhaust cam to the oil pump.  But no idea how this would effect the 2.0L 912 performance wise.

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Awesome, exactly what I wanted to hear. Thanks

 

It's a 920 engine; I'd have thought that if it's mostly the same motor as the 910 (slightly de-stroked?) with the same camshafts, it should still be beneficial? Maybe just not as much.

 

Anything I can do to help the low end without sacrificing elsewhere is good. It's definitely not the most responsive car off-boost

Edited by cammmy

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It's definitely not the most responsive car off-boost

 

Flat as a witch's tit is a phrase that springs to mind. 

 

Wish I knew what a green dot pulley was :getmecoat:

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Have a google. Basically the cam timing was changed for emissions purposes. This was detrimental to lower rpm response.

Looks like the GT3 has a green dot on the exhaust already so will see what's on the oil pump. I got stuck on this a while ago and have been waiting for another free weekend and some tools to have another crack at it

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Had a look at the pulleys. The inlet pulley has a definite coloured dot on it. The exhaust pulley looks like the colour has faded away as it's definitely not green but it's also definitely not red or blue; looks almost grey. The pulley on the oil pump is exactly the same.

 

Might pull the pulley off the oil pump and line the keyway up with the exhaust pulley and see how they match. If it matches I'll chuck it on the inlet.

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Righto, just got everything back together today. I can confirm that my GT3 had a green dot on the exhaust and a red dot on the inlet. The oil pump pulley had a green dot which i've now swapped with the red dot. So if you have a GT3, you don't need to buy any pulleys, just swap the oil pump to the inlet.

Not driven it yet but hoping it'll have some more poke down low.

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Went fine, can't say I noticed a night and day difference but the car was off the road for about 2 months, so wasn't really a back to back comparison.

I'm part way through my ECU swap now, so I'm hoping the pulleys and a dyno tune will improve the bottom end a fair bit.

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Nope, no issues. I don't think the timing change is that drastic anyhow; it's something like 4 degrees of advance on the inlet?

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Do you have a GT3? You'll need to buy a pulley if you have one of the 2.2L engines.

If you have to buy a pulley, it might be worth getting verniers instead. More faff to set up, but you can dial in whatever settings you want.

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