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number1
28-02-2007, 22:52
Does anyone knoe What are the inlet and exhaust valve sizes for the following??

16v head
williams head
megane head

Cheers
Dave

MAXIBOY
01-03-2007, 00:15
Does anyone knoe What are the inlet and exhaust valve sizes for the following??

16v head 30 inlet 28.5 exhaust
williams head 33 28.5
megane head 33 28.5

Cheers
Dave

Justin..
01-03-2007, 00:15
thought the meg had bigger valves than a willy?

number1
01-03-2007, 00:17
Yeh that was the assumption i was under

dave

MAXIBOY
01-03-2007, 00:20
not sure now you say that. exhaust are identical and i just fitted 33mm megane valves to my 1.8 head. thought willy,s were the same just megane has smaller ports

number1
01-03-2007, 00:21
measured my inlet valves on my gasflowed head earlier with verniers and they are 31mm exactly....

MAXIBOY
01-03-2007, 00:23
right i,m confused now. maybe the 1.8,s are 31mm standard and the others are 33mm then

number1
01-03-2007, 00:24
vernier calipers not vernier pulleys lol, just wondering im measuring the diameter of the valve, maybe i should measure the inner edge of the seat??

MAXIBOY
01-03-2007, 00:25
no thats right valve head diameter

number1
01-03-2007, 00:27
31mm for sure then, i presume thats 16v size, just wondered what williams ones were as megane ones are supposed to be bigger again..

Dave

MAXIBOY
01-03-2007, 00:35
megane are 33mm that,s what i,ve got.

BenR
01-03-2007, 00:44
ex all the same.

16v in 30.7mm
willy in 31.7mm
meg in 33mm

MAXIBOY
01-03-2007, 00:47
cheers ben. i was wrong again. i thought willy,s and megane were the same. sorry for the confusion

BenR
01-03-2007, 01:02
no worries.

DaveH
01-03-2007, 01:10
Slightly off topic but if you were to, for instance build a big valve, gas flowed williams head, what size valves would you use- 33mm?

MAXIBOY
01-03-2007, 01:16
could be wrong again but i think you can go 34 or 34.5mm

BenR
01-03-2007, 01:43
I've got 35mm custom valves, but it takes a SERIOUS amount of work for each port to get the valve size to work. About one evening PER inlet port.

= not cheap.

for a daily drive the willy oe megane valves are more than fine.

number1
01-03-2007, 19:49
might need to get the slightly more accurate verniers out lol

Dave

DaveH
01-03-2007, 19:57
I've got 35mm custom valves, but it takes a SERIOUS amount of work for each port to get the valve size to work. About one evening PER inlet port.

= not cheap.

for a daily drive the willy oe megane valves are more than fine.

So would a willy head with 33mm inlet valves give a noticeable gain over standard and not need too much work?

BenR
01-03-2007, 21:02
appropriately modified yes, but a well modified stock valve sized willy head is perfectly good.

DaveH
02-03-2007, 01:45
Cheers Ben.