Oversize Valves +0.5mm or 1.0mm?
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From: The Tukee, AZ, United States
I believe that over sized valves show very little to non at all in top end flow. Most gains are in the low to mid range and are more than likely not worth the problems they can cause such as close piston to valve and valve to valve clearances.
All Motor Mentor
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From: 902, Nova Scotia, Canada
Re: Oversize Valves +0.5mm or 1.0mm? (Johnny_9)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Johnny_9 »</TD></TR><TR><TD CLASS="quote">Any use? Some say no use...please feedback</TD></TR></TABLE>
Unless you're running a well built H22, no. If flow is what you need, you need to go see a QUALIFIED head porter who knows what they're doing. They will also be best qualified to tell you if you "need" oversize valves for what you want to do.
Unless you're running a well built H22, no. If flow is what you need, you need to go see a QUALIFIED head porter who knows what they're doing. They will also be best qualified to tell you if you "need" oversize valves for what you want to do.
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From: B.Land
Re: (GoingGoingGone)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GoingGoingGone »</TD></TR><TR><TD CLASS="quote">I believe that over sized valves show very little to non at all in top end flow. Most gains are in the low to mid range and are more than likely not worth the problems they can cause such as close piston to valve and valve to valve clearances.</TD></TR></TABLE>
Thanks - did some seraches on other sites - that summariezes it well
Thanks - did some seraches on other sites - that summariezes it well
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From: B.Land
found this...............>>>>>
Oversized valves for N/A 1.8L applications with big cams. they don't increase the max. flow rate that much more,
you have to deshroud, port, and change your seats. you have to worry about clearances distances between the intake and exhaust valves at overlap.
they shift your powerband really high up.
the bang for the buck in those scenarios (1.8L, N/A, 12mm lift cams) is not there.
for moderate lift cams (i.e. 11.5-11.8mm max lift) and for people who want a high powerband these may be beneficial.
they may benefit bigger displacement N/A as well (i.e. 2L).
they definitely benefit FI people who are willing to pay for the deshrouding and porting that goes with them .
Oversized valves for N/A 1.8L applications with big cams. they don't increase the max. flow rate that much more,
you have to deshroud, port, and change your seats. you have to worry about clearances distances between the intake and exhaust valves at overlap.
they shift your powerband really high up.
the bang for the buck in those scenarios (1.8L, N/A, 12mm lift cams) is not there.
for moderate lift cams (i.e. 11.5-11.8mm max lift) and for people who want a high powerband these may be beneficial.
they may benefit bigger displacement N/A as well (i.e. 2L).
they definitely benefit FI people who are willing to pay for the deshrouding and porting that goes with them .
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From: So Cal
Re: Oversize Valves +0.5mm or 1.0mm? (Master of the Universe)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Master of the Universe »</TD></TR><TR><TD CLASS="quote">+1mm works real nice wid 81mm bore.
Fo-shizzay!!!!
</TD></TR></TABLE>
But no! It will Kill teh Veloctiy'z!!11!~one
Fo-shizzay!!!!
</TD></TR></TABLE>But no! It will Kill teh Veloctiy'z!!11!~one
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From: CA
Re: Oversize Valves +0.5mm or 1.0mm? (Combustion Contraption)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Combustion Contraption »</TD></TR><TR><TD CLASS="quote">
But no! It will Kill teh Veloctiy'z!!11!~one</TD></TR></TABLE>
PFFT! Everyone in the know, knows that bigger valves = bigger ballz!!!!!!
But no! It will Kill teh Veloctiy'z!!11!~one</TD></TR></TABLE>
PFFT! Everyone in the know, knows that bigger valves = bigger ballz!!!!!!
Re: Oversize Valves +0.5mm or 1.0mm? (Phil M)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Phil M »</TD></TR><TR><TD CLASS="quote">
PFFT! Everyone in the know, knows that bigger valves = bigger ballz!!!!!! </TD></TR></TABLE>
Ehhh, flowz es oberated
PFFT! Everyone in the know, knows that bigger valves = bigger ballz!!!!!!
</TD></TR></TABLE>Ehhh, flowz es oberated
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