Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor?
11-23-2005, 01:39 PM
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Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor?
aside cam gear adjustment, what are effects of clearances being set too loose/tight
1. if it creates overlap, would both intake and exhaust side have to be too loose or tight?
2. same thing for a/f ratio, would both intake and exhaust have to be too loose or too tight?
3. if its too loose, does it mean its going to run on the lean side or rich?
1. if it creates overlap, would both intake and exhaust side have to be too loose or tight?
2. same thing for a/f ratio, would both intake and exhaust have to be too loose or too tight?
3. if its too loose, does it mean its going to run on the lean side or rich?
11-23-2005, 05:19 PM
#2
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Re: Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor? (vtec.dc2)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtec.dc2 »</TD></TR><TR><TD CLASS="quote">aside cam gear adjustment, what are effects of clearances being set too loose/tight
1. if it creates overlap, would both intake and exhaust side have to be too loose or tight?
2. same thing for a/f ratio, would both intake and exhaust have to be too loose or too tight?
3. if its too loose, does it mean its going to run on the lean side or rich?</TD></TR></TABLE>
Yes, its going to have some effect on duration and a/f ratios. How much? Well I guess that would depend on how far "off" the valves are. I would be more worried about burnt valves from a tight adjustment then I would how its going to effect overlap and my a/f ratios....
1. if it creates overlap, would both intake and exhaust side have to be too loose or tight?
2. same thing for a/f ratio, would both intake and exhaust have to be too loose or too tight?
3. if its too loose, does it mean its going to run on the lean side or rich?</TD></TR></TABLE>
Yes, its going to have some effect on duration and a/f ratios. How much? Well I guess that would depend on how far "off" the valves are. I would be more worried about burnt valves from a tight adjustment then I would how its going to effect overlap and my a/f ratios....
11-24-2005, 06:17 AM
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Re: Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor? (Hybrid93Eg
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid93Eg »</TD></TR><TR><TD CLASS="quote">
Yes, its going to have some effect on duration and a/f ratios. How much? Well I guess that would depend on how far "off" the valves are. I would be more worried about burnt valves from a tight adjustment then I would how its going to effect overlap and my a/f ratios.... </TD></TR></TABLE>
in my case it would probaly be on the loose side, i think i may have overlap, cause my boost is stable until vtec.. and i'm at full boost for at least 2000rpm before vtec
Yes, its going to have some effect on duration and a/f ratios. How much? Well I guess that would depend on how far "off" the valves are. I would be more worried about burnt valves from a tight adjustment then I would how its going to effect overlap and my a/f ratios.... </TD></TR></TABLE>
in my case it would probaly be on the loose side, i think i may have overlap, cause my boost is stable until vtec.. and i'm at full boost for at least 2000rpm before vtec
11-24-2005, 09:39 AM
#4
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Re: Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor? (Hybrid93Eg
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtec.dc2 »</TD></TR><TR><TD CLASS="quote">
in my case it would probaly be on the loose side, i think i may have overlap, cause my boost is stable until vtec.. and i'm at full boost for at least 2000rpm before vtec</TD></TR></TABLE>
Loose valves would DECREASE the amount of overlap.. Of course you will have a certain amount of overlap, its what helps to fill the chamber. I don't see what you are trying to get at. When you say "stable" what do you mean? Does it drop off 4-5psi? Does it go all over the place?
in my case it would probaly be on the loose side, i think i may have overlap, cause my boost is stable until vtec.. and i'm at full boost for at least 2000rpm before vtec</TD></TR></TABLE>
Loose valves would DECREASE the amount of overlap.. Of course you will have a certain amount of overlap, its what helps to fill the chamber. I don't see what you are trying to get at. When you say "stable" what do you mean? Does it drop off 4-5psi? Does it go all over the place?
11-24-2005, 03:15 PM
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Re: Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor? (Hybrid93Eg
it drops, about 1-2psi and but it goes in/out 1-2psi.. its stable until it hits vtec at ~6k rpm
if loose valves decrease overlap, then.. does same goes for a/f ratio? does it lean out when its loose or runs more rich
if loose valves decrease overlap, then.. does same goes for a/f ratio? does it lean out when its loose or runs more rich
11-25-2005, 10:06 AM
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Re: Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor? (vtec.dc2)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtec.dc2 »</TD></TR><TR><TD CLASS="quote">aside cam gear adjustment, what are effects of clearances being set too loose/tight
1. if it creates overlap, would both intake and exhaust side have to be too loose or tight?
2. same thing for a/f ratio, would both intake and exhaust have to be too loose or too tight?
3. if its too loose, does it mean its going to run on the lean side or rich?</TD></TR></TABLE>
1. if it creates overlap, would both intake and exhaust side have to be too loose or tight?
2. same thing for a/f ratio, would both intake and exhaust have to be too loose or too tight?
3. if its too loose, does it mean its going to run on the lean side or rich?</TD></TR></TABLE>
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11-29-2005, 07:29 PM
#9
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Re: Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor? (vtec.dc2)
tight valve lash = more duration, loose valve lash = less duration
afr will be effected if you change these things after a tune, if its loose and you tune it that way it wont be a problem unless you tighten it, etc.
afr will be effected if you change these things after a tune, if its loose and you tune it that way it wont be a problem unless you tighten it, etc.
11-30-2005, 01:00 PM
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Re: Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor? (JDogg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDogg »</TD></TR><TR><TD CLASS="quote">tight valve lash = more duration, loose valve lash = less duration
afr will be effected if you change these things after a tune, if its loose and you tune it that way it wont be a problem unless you tighten it, etc.</TD></TR></TABLE>
so as far as a/f goes, if its more loose, then its more lean or rich? - if i'm to readjust after tuning
afr will be effected if you change these things after a tune, if its loose and you tune it that way it wont be a problem unless you tighten it, etc.</TD></TR></TABLE>
so as far as a/f goes, if its more loose, then its more lean or rich? - if i'm to readjust after tuning
11-30-2005, 01:25 PM
#11
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Re: Questions about valve adjustment affecting A/F ratio and overlap on dohc vtec motor? (vtec.dc2)
its hard to say exactly, but generally it would probably get richer if the lash loosens up after the tune... but probably not by much.
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