Mr chip, can you help me settle a debate please?

Vauxhall C20XE inlet valves.....1 piece or 2 piece? Its just it says on a little book i read that standard OE C20XE inlet valves are infact 1 peice.

Wouldn't know off the top off your head would you?

 

at this particular time, he's probably in bed

 

1 piece as far as i know

 

Thats what i got told by a friend who does my headwork.

Been speaking to Jamie F & he says they are 2 piece. Am really confused now

 

2 piece mate, the heads are friction welded on.

 

So technically they are 2 piece but one piece as we see em

 

if you look closely you can see the join, but yes obvioulsy they are only one actual item to replace you dont bolt the top on or anything, lol

 

Ballbags

So why does that bloody order book say 1 piece?!

I though the magnet test was pretty fool proof for finding out obviously not

 

you can get one piece for when you need to rev hard and the head not come off and land on a piston.

ive just ordered some in 214N, only about 15 quid each.

im hoping to get some nimonic80 1mm oversize ones made at some point, but they will be about 60 qiud a valve

 

Cool, high tensile then

So what RPM should i think about changing them for 1 piece? I mean there's not much point having high RPM with a supercharger, because with the gearing it would be boosting too much and rip itself to bits.

 

just changing the pully and rev it higher!!

lol

Alex

 

Spence, if you are using the mini charger then i dont think you will need to rev it any more than standard mate.

 

Thats what i was thinking

J871yhk, If i change the pulley to make it rev higher, then i will lose low down power because of the low RPM (caused by a bigger pulley to allow a higher rev limit on the engine whilst keeping the charger safe)

Its all about finding the perfect combination, low down torque to help the engine spool up a lot quicker and get the power down better, then higher up the rev range for some nice smooth acceleration.