z6 vs y8 vtec head
I'm not sure about the emissions laws (or lack there of) in Florida. If you have strick emissions laws, you'll need to use the y8 head. But the z6 head flows better, it will be best with a y8 intake manifold too.
Well i searched thinking there would be but i didnt see none...so anyways a new thread maybe there are new things too say about these head and pros and cons about it...anyone?...
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y8 better for all motor build or if you keeping it stock. z6 better for turbo build. my 2 cents, now go search before you ask which tranny is better
well first of all i searched thats y im asking this kinda stuff again becuz i didnt find nothin i guess there old threads...and number 2 im going boost....so i dunno what head is better..im pretty sure there both the same crap more or less but i see sum ppl choose a z6 instead of a y8
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Joined: Jan 2006
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From: Rochester, New York -> Santa Clara, CA
I hav ethe stock Z6block and head, I'd go with the Y8 because it's a nice head swap, from what I hear it's better than the D16Z6 setup though I have no personal exp w/ a D16Y8
the z6 will outflow the y8 head either way.
there was a test done.. i forgot where but on another thread. A guy had a y8 and a z6 head.. in stock form the z6 out flowed the y8 head. Then he did another test in which he did a 3angle valve job.. PnP.. the y8 had a more significant gain then the z6 but the z6 still outflowed it.. i think it was like 205cfm for the y8 and 210cfm for the z6.
also by the way it is designed the y8 will have a better mid-range then the z6, but the z6 will have a better high end then the y8.
Compression ratio for the z6/y7 is like 9:6:1 i can't remember correctly and the y7/y8 is like 9:9:1? I'm not sure off the top of my head.. but the z6 has a lower compression on the y7 block than the y8 on the y7.
oh and the swap on the y8 would be a direct fit on your y7 block. If you plan on using a z6, then you would need to use the z6 distributor and remove the two wire connector and run the black/yellow wire to the empty slot in the main connector. The blue wire is an extra signal wire and is something that you won't need.... Use a pin from your old distributors connector and put it into the z6 distributor... If you do not want to cut up your old distributor you could hard wire the black/yellow wire into the cars harness and not use the plug there... and walla swap done! haha.
hoped that helped!
Modified by chippy at 6:18 AM 3/5/2006
Modified by chippy at 6:20 AM 3/5/2006
there was a test done.. i forgot where but on another thread. A guy had a y8 and a z6 head.. in stock form the z6 out flowed the y8 head. Then he did another test in which he did a 3angle valve job.. PnP.. the y8 had a more significant gain then the z6 but the z6 still outflowed it.. i think it was like 205cfm for the y8 and 210cfm for the z6.
also by the way it is designed the y8 will have a better mid-range then the z6, but the z6 will have a better high end then the y8.
Compression ratio for the z6/y7 is like 9:6:1 i can't remember correctly and the y7/y8 is like 9:9:1? I'm not sure off the top of my head.. but the z6 has a lower compression on the y7 block than the y8 on the y7.
oh and the swap on the y8 would be a direct fit on your y7 block. If you plan on using a z6, then you would need to use the z6 distributor and remove the two wire connector and run the black/yellow wire to the empty slot in the main connector. The blue wire is an extra signal wire and is something that you won't need.... Use a pin from your old distributors connector and put it into the z6 distributor... If you do not want to cut up your old distributor you could hard wire the black/yellow wire into the cars harness and not use the plug there... and walla swap done! haha.
hoped that helped!
Modified by chippy at 6:18 AM 3/5/2006
Modified by chippy at 6:20 AM 3/5/2006
the y8 has a smaller combustion chamber and yeaild higher compression...this also helps with avoiding detonation...but the z6 head does flow better. you may have to repin the dizzy plug depending on yer setup.
reall helpful there bud...i guess yea ill go with a y8 head instead of going through the hassel of a all that wiring i hate ghetto riging sh*t...But another quik question...by the way yes u are right a y8 head would bump up the compression to 9.9:1....im also looking forward to buying pistons...what compression pistons do i buy...like im confused now because i thought that slapping a y8 head would just bring up the compression to that of a stock ex motor(9.6:1)....but i dunno y would it bring up the compression that high unless the y7 bottom end is different then the y8 bottom end...im pretty sure honda didnt great a head gasket for the d16y8 and a different from for the d16y7?
i think the h/g are differant i know that the y7 does have higher compression because the head that was on there has a larger combustion chamber and therefore the higher compression pistons will still yeild a lower compression. but the y8 head has a small combustion chamber so the pistons that go with the head have to be power compression is order to yeild the same compression. when you mix and match you get higher compression thats why its done.
head gaskets are the same. I bought headgaskets for both motors, and they have the same part numbers on them. It seems like the y7 has a more domed piston. I can't remember though, i have it all in my garage, but i have gone back to running all y8 motor, so i can't verify anymore. But if you run a y7 bottom end, with a y8 head, your compression should be 9.96:1. If you run a y8 motor complete, then it'd be 9.6:1.
If your gonna build internaly, thats differnt all together. Do a search, if your boosting, then i'd stay around stock, if your gonna boost 30 psi, then i'd lower it a little. If your going NA then up the compression, and swap the cam, and port the hell out of it. What compression its up to you. If you swap in some zc pisons, you could up your compression insanely. You have lots to decide still, make some decisions and search others setups and have fun.
If your gonna build internaly, thats differnt all together. Do a search, if your boosting, then i'd stay around stock, if your gonna boost 30 psi, then i'd lower it a little. If your going NA then up the compression, and swap the cam, and port the hell out of it. What compression its up to you. If you swap in some zc pisons, you could up your compression insanely. You have lots to decide still, make some decisions and search others setups and have fun.
Well ive searched and i dont find nothing...the thing is that if doing this mini me swap will bump the compression to 9.9:1 and i buy, lets say wiseco 8.5:1 pistons for a y8, how do i calculate the actual compression...do i just add the .3 extra? u get me thats what im im having the hard time figuring out
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tobe1424 »</TD></TR><TR><TD CLASS="quote">Well ive searched and i dont find nothing...the thing is that if doing this mini me swap will bump the compression to 9.9:1 and i buy, lets say wiseco 8.5:1 pistons for a y8, how do i calculate the actual compression...do i just add the .3 extra? u get me thats what im im having the hard time figuring out</TD></TR></TABLE>
the y7 has higher compression because of the pistons....i think the stroke is the same as the y8 but thats just a guess. if the stroke is the same and you use a y8 head it will yeild the SAME compression as the pistons say they will.
the y7 has higher compression because of the pistons....i think the stroke is the same as the y8 but thats just a guess. if the stroke is the same and you use a y8 head it will yeild the SAME compression as the pistons say they will.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tobe1424 »</TD></TR><TR><TD CLASS="quote">O ok...so does anyone know if the y8 have the same stroke as a y7...anyone...?</TD></TR></TABLE>
yes both have 90mm stroke
yes both have 90mm stroke
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tobe1424 »</TD></TR><TR><TD CLASS="quote">so then it would be cool to just get lets say 8.5:1 pistons for a y8 with a y8 head on my y7 block and the compression would be 8.5:1?</TD></TR></TABLE>
yes the compression depends on head and pistons, so you will have 8.5:1
yes the compression depends on head and pistons, so you will have 8.5:1
Why don't you just leave the Y7 alone and turbo it?
PM user "tgreaves" he had a stock-internal Y7 with AEM EMS and a T3 turbo@ 12 psi and ran 12.75 @ 109
https://honda-tech.com/zerothread?id=1315461
PM user "tgreaves" he had a stock-internal Y7 with AEM EMS and a T3 turbo@ 12 psi and ran 12.75 @ 109
https://honda-tech.com/zerothread?id=1315461



