Valve to piston clearance (aftermarket)

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Wed 27 Jun 2007 20:10
Valve to piston clearance (aftermarket) - track
Bit of a techy question, Im running a 2.0 16v peugeot engine (gti6) but it has been restroked to 2.1 litre and the cam has been reground for longer duration on the inlet side. The cam should be set to 2.66mm lift at TDC however when I checked the valve to piston clearance at TDC I get it at 2.1mm, this is before the valves have been lapped in and also before the head is fully torqued down, I still need to torque it a further 160 degrees.
Im wondering just how much lift at TDC can safely run with as I am looking for peak power from the engine with the current set up.
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Thu 28 Jun 2007 22:33
valve to piston clearance (aftermarket) - hm
mate, would sign up to a gti website or something/...

www.306gti6.com

I used these guys when I was running myh 306 S16..
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Fri 29 Jun 2007 09:29
Valve to piston clearance (aftermarket) - tr7v8
OK, first you need to ask whoever reground the cams, they should know.
If you're still in doubt then do a dummy build with a used headgasket & put plastecine on the tops of the pistons. Turn engine over by hand then strip & cut plastecine with a scapel & measure how much thickness & hence clearance you have. I forget the exact figures without looking it up & I'm in a hotel in Dresden at the mo. Go on the Guy Croft site or similar & he'd tell you. It'd be worth getting a decent engine tuning & rebuild book as that'll explain it.
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Sun 1 Jul 2007 18:30
Valve to piston clearance (aftermarket) - track
Im on the gti6 site anyway but the engine isnt in a 306, its in a 205 and the question isnt answered there either as its not a standard cam or a standard crankshaft.
Also dont need to use the plasticine method as I know how much clearance there is now.
What I need to know is how much there should be minimum so I can edvance the cam up to that point.
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Sun 1 Jul 2007 21:46
Valve to piston clearance (aftermarket) - blue_haddock
try www.205gtidrivers.com also or speak to a decent engine builder with experience of this engine ie DES developments, Hi-FLow Head, QEP etc
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