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a6 head vs. SOHC VTEC head

3558 Views 19 Replies 7 Participants Last post by  qweakers
I was wondering what your opinions of a built version of each were. Im think about really building up the stock a6 head i have now but i have read a lot of guys are running and like sohc vtec setup, my crx is a daily driver and i do auto-x and light road racing
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if your staying Obd0 you will never fully benefit from the vtec head so i'd say go with the A6 head built. By staying obd0 and using vtec there really is'nt a realy deal way to use vtec, i mean you can get an expensive vafc controller but it still is'nt the same, you just can't tune it the way you can if you go obd1. If your converting to obd1 though the Z6 will always win, its just a better design all around.
Interesting, is there a thread you can link me to or website that can explain obd0 1 and 2? also do you feel like that Z6 or y8 head would be better than the a6 if converted to obd 1?
godruler said:
if your staying Obd0 you will never fully benefit from the vtec head so i'd say go with the A6 head built. By staying obd0 and using vtec there really is'nt a realy deal way to use vtec, i mean you can get an expensive vafc controller but it still is'nt the same, you just can't tune it the way you can if you go obd1. If your converting to obd1 though the Z6 will always win, its just a better design all around.
There are ways to use OBD0 and vtec you can use Turboedit to get your fuel/timing maps and then use any various ways to activate VTEC. Of course a OBD1 conversion is a better option but if your dead set on staying OBD0 you have a few options. I for one love the A6 head.
if i were to swap to a vtec head i would swap to obd 1 to be able to tune it more but since im on a budget and kinda want to do something different, i'll probably just stick with a6 head i was just curious. Why do you like the a6 head better?
If you run a built non-VTEC you're going to have at the least a crappy idle. I love the A6, but to make serious power you'll need a big cam, which is going to suck at the low end.

If you do use a VTEC head, you should convert to OBD1, running an RPM switch or something isn't right, Running OBD1 with the correct ECU is the only right way to run a VTEC head.
well since it will most likely be daily driven i would want it to idle very good and i already planned on switching the ecu with the compatible vtec head and getting a cam that would somewhat get the best of both worlds and a good vtec controller. I would probably have a daily driver setup and auto-x and road setup tune too and if i did do the swap i thought about doing the whole hondata thing too or having it sent out.
perosis said:
Interesting, is there a thread you can link me to or website that can explain obd0, 1 and 2?
OBD explanation that I found:

"OBD stands for On Board Diagnostics. Every modern car has a version of OBD and it's basically an engine monitoring system. It consists of many different sensors in strategic locations that monitor various aspects of the engine's performance. Some examples of the sensors are O2 sensors that monitor the air to fuel mixture, the throttle position sensor that senses how open the throttle plate is at any given moment, and intake temperature sensor that monitors the temperature of the intake air. All of these sensors are monitored by the ECU, the car's brain monitors the OBD system and changes variables according to pre-programmed specifications. There are currently 3 versions of OBD and each version gets progressively more complex and stricter on the amount flexibility it will allow before taking action to prevent what it sees as a potentially engine damaging situation. OBD1 started with the 5th generation civic 1992-1995. OBD2 continued with the 6th generation 1996-2000 and the latest version is OBD3 and can be found on the 7th gen. civic 2001-???."
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baker you kick ass, i owe you beer if i ever see you
how hard do you think it would be to convert to obd 1 or 2 from stock obd?
if you are talking about going form OBD0 -->OBD1 they make conversion harnesses for it. practical everyone i know run OBD1 or OBD0, they never swap over to OBD2. the support isn't there for it. people running OBD2 usually swap back to OBD1. basically swapping to OBD1 requires a conversion harness, ecu, dizzy, 4 wire O2 sensor. put the stuff on and wire it up and you can pretty much call it a day. if i missed anything somebody please fill in the gaps.
thanks man. would you all say that a built y8 or z6 head on obd 1 is more tunable* or able to get better/more HP than a built a6 on obd 0 or 1?
perosis said:
thanks man. would you all say that a built y8 or z6 head on obd 1 is more tunable* or able to get better/more HP than a built a6 on obd 0 or 1?
Absolutely.
generally yes there is alot more support for obd1. it all depends on how much money you want through at your motor.
i see, do you also think that obd 2 is less supported because its so new that the software/hardware hasnt been developed yet beause its kinda expensive?
Email Bisi he will give you his advise on the A6 head. He is also a H-T member. Loves the non vtec d series.
well if i had a clue who bisi is, i would get a hold of him, yes im new to this whole internet forum chat stuff
perosis said:
i see, do you also think that obd 2 is less supported because its so new that the software/hardware hasnt been developed yet beause its kinda expensive?
OBD-2 has been around since 96, and the support is there if you look for it. OBD-1 is just easier to work with.
here is some info regarding chipping a obd2 ecu from pgmfi.org

http://www.pgmfi.org/twiki/bin/view/Lib ... ippingOBD2

really think that just going obd1 and using crome, uberdata, hondata, neptune (and what ever else to tune odb1) would be easier and cheaper.
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