NC30 big valve mod

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twist&go
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NC30 big valve mod

Post by twist&go » Fri Dec 14, 2012 12:48 pm

has anyone heard of or seen a nc30 fitted with bigger inlet and exhaust valves????
a local racer who runs a nc30 tells me that hes running bigger valves both In and Ex its a self tuned motor and hes done all the work him self.
so is he feeding me total shite or can it be done
any advice on the matter would be mega
:rocks:

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vfrman
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Re: NC30 big valve mod

Post by vfrman » Fri Dec 14, 2012 1:00 pm

I'm gonna call BS on that one. The valves are already pretty crowded in the head. Bigger valves would take a lot of work, and probably a re-designed head.

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Yakama
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Re: NC30 big valve mod

Post by Yakama » Fri Dec 14, 2012 1:01 pm

As Tony he spoke to someone recently who had fitted bigger valves

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CMSMJ1
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Re: NC30 big valve mod

Post by CMSMJ1 » Fri Dec 14, 2012 2:46 pm

I have this from Chris at Dynopro..

motor strip build £450
new gaskets £86
piston kit £575
rebore £150 (dont worry about the liner thickness there is enough left if done correctly)
machine pistons weight match etc £125
suggest re shelling motor at this point £130 ish

additional work
tuned heads that work £250 inc shims and cam shimming etc
reduce weight and balance cam idle gears £150
adjustable cam gears £250
flow crank cases incorporate extra breather £125
blue print gearbox and modify clutch £100

1mm oversize valve kit inc seat adjustment etc £350
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

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VFRkieran
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Re: NC30 big valve mod

Post by VFRkieran » Fri Dec 14, 2012 3:03 pm

Hasnt the g force motor got bigger Ti valves too? Must admit it does look like a proper squeeze in there for anything much over 1mil.

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Drunkn Munky
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Re: NC30 big valve mod

Post by Drunkn Munky » Fri Dec 14, 2012 3:13 pm

£86 for a gasket kit, that's cheap

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JC120
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Re: NC30 big valve mod

Post by JC120 » Fri Dec 14, 2012 6:23 pm

There's a local mechanic named Jim Granger who's fitted some. The valves where custom made and took a few batches to get right. He mostly works on RC30's but does work on the 400 v4s too. I got to check the valves out in person. I believe they're the same spec as the gforce ones.
V4ia addict

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