K20a2 vs K20a3 heads
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From: Somewhere inbetween NV and NJ
Re: K20a2 vs K20a3 heads (Fcmike)
the k20a2, found in the older model (02-04) rsx type-s, has alot more power when it hits vtec ... you WILL feel it pull ... in the k20a3, which is found in the base model (02-06) rsx, you wont even be able to hear it unless your open head nor will you feel a pull (i have driven in both cars) ... i also heard a3 vtec kicks in too early so there isnt enough oil press to feel the kick but im not sure what it really is with the vtec on the a3 ... all you need to know is k20a2 is better ... lol
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From: Racine, WI, United States
Re: K20a2 vs K20a3 heads (inkong)
Okay well here is how the K20a3 works.
We don't have an adjustable I-VTEC feature. I-VTEC engages at 2200 RPM and we only have I-VTEC on the intake cam lobe. Many people call the K20a3 a I-VTEC(E) type motor. The "E" is supposed to stand for economy i guess. However what you will notice is that the K20a3 has a lot more low end power than the a2's. However you won't have the peak power as they do. Redline is at 6800 RPM. The K20a3 has a compression of 9.8:1 where the a2 is at 11.0:1. So the a3 is pretty much setup to run an off the shelf turbo kit pretty reliably at low boost. I love this motor, it is pretty competitive with the RSX-S's in auto-x in my EP3. KPRO is a must!
The K20a2 (RSX-S or Euro Spec Civic Type R) have a redline of 7900 RPM with a base horsepower of 200HP to the crankshaft.
Now i don't know what everyone considers when and how hard the I-VTEC engages as how powerful the motor is! Frankly i believe it's quite ignorant and idiotic. The a3 is a pretty stout motor and i still believe that it is much better than a B16. If you compare the two motors together, the K20a3 produces about the same HP but delivers much more TQ than the 1.6L VTEC. So if you are considering a swap the a3 is a cheap and reliable motor to put in and whoop the sh*t out of some B16 and B18's.
We don't have an adjustable I-VTEC feature. I-VTEC engages at 2200 RPM and we only have I-VTEC on the intake cam lobe. Many people call the K20a3 a I-VTEC(E) type motor. The "E" is supposed to stand for economy i guess. However what you will notice is that the K20a3 has a lot more low end power than the a2's. However you won't have the peak power as they do. Redline is at 6800 RPM. The K20a3 has a compression of 9.8:1 where the a2 is at 11.0:1. So the a3 is pretty much setup to run an off the shelf turbo kit pretty reliably at low boost. I love this motor, it is pretty competitive with the RSX-S's in auto-x in my EP3. KPRO is a must!
The K20a2 (RSX-S or Euro Spec Civic Type R) have a redline of 7900 RPM with a base horsepower of 200HP to the crankshaft.
Now i don't know what everyone considers when and how hard the I-VTEC engages as how powerful the motor is! Frankly i believe it's quite ignorant and idiotic. The a3 is a pretty stout motor and i still believe that it is much better than a B16. If you compare the two motors together, the K20a3 produces about the same HP but delivers much more TQ than the 1.6L VTEC. So if you are considering a swap the a3 is a cheap and reliable motor to put in and whoop the sh*t out of some B16 and B18's.
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From: Somewhere inbetween NV and NJ
Re: K20a2 vs K20a3 heads (20CiviC02Si)
the way you explain the i-vtec in the a3 makes it seem like you only have the vtc performance of the i-vtec ... intake camshaft lift is lowered in the lower rpms to become more fuel efficient while the exhaust camshaft lift is fully opened ... it does help the lower rpm but where is the full vtec effect itself ... isnt vtec supposed to increase the lift of both intake and exhaust values a greater amount to increase flow and simulate somewhat of the same affect as turbo just without forced compressed air ... im not saying your wrong about how the a3 works and it is more powerful throughout the ENTIRE power band because of its i-vtec(e), which ive only heard of once and didnt know it doesnt have the adjusted feature, but the a2 has alot more pull when the lift is increased ... you cant say thats not power when your air and fuel ratio inside the engine itself increases ... its just like turbo forcing in more air when boosting ... correct me if im wrong
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From: Innovative Motorworks
Re: (tnhatch03)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tnhatch03 »</TD></TR><TR><TD CLASS="quote">^ im surprised no one said this first. if i am not mistaken.
A2 = 3 lobes on intake, 3 lobes on exhaust.
A3 = 2 lobes on intake, 3 lobes on exhaust.
= visual difference
hth.</TD></TR></TABLE>
You know what I ment.
A2 = 3 lobes on intake, 3 lobes on exhaust.
A3 = 2 lobes on intake, 3 lobes on exhaust.
= visual difference
hth.</TD></TR></TABLE>
You know what I ment.
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From: Racine, WI, United States
Re: (tnhatch03)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tnhatch03 »</TD></TR><TR><TD CLASS="quote">^ im surprised no one said this first. if i am not mistaken.
A2 = 3 lobes on intake, 3 lobes on exhaust.
A3 = 2 lobes on intake, 3 lobes on exhaust.
= visual difference
hth.</TD></TR></TABLE>Actually the A3 = 3 lobes on intake, and 2 lobes on exhaust. I-VTEC function is on the intake cam. And what i mean is that the I-VTEC does engage, it's just a seamless engagement.
A2 = 3 lobes on intake, 3 lobes on exhaust.
A3 = 2 lobes on intake, 3 lobes on exhaust.
= visual difference
hth.</TD></TR></TABLE>Actually the A3 = 3 lobes on intake, and 2 lobes on exhaust. I-VTEC function is on the intake cam. And what i mean is that the I-VTEC does engage, it's just a seamless engagement.
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From: Somewhere inbetween NV and NJ
Re: (adrw1)
unless they were going turbo and felt that it would help besides that i dont think so ... most people modify their heads so it wouldnt be stock a3 anyway ... k series head is a k series head the difference is what is in them ... the stock heads are mass produced so none of them are perfect anyway ...
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Re: (DiMpL3s)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DiMpL3s »</TD></TR><TR><TD CLASS="quote"> K20a2 vs K20a3 heads....
all u need to know is that the k20a3 head sucks.....
TTT</TD></TR></TABLE>
I'm with inkong ... the A3 head doesn't suck ... the K20A3 makes good power for what it is ... very usable and it has one of the flatest torque curves I've seen. I've had zero complaints running this motor on the track ... just take some weight out of the EP3 and you're good to go!
The OP asked for visual differences in the head design ...
all u need to know is that the k20a3 head sucks.....
TTT</TD></TR></TABLE>
I'm with inkong ... the A3 head doesn't suck ... the K20A3 makes good power for what it is ... very usable and it has one of the flatest torque curves I've seen. I've had zero complaints running this motor on the track ... just take some weight out of the EP3 and you're good to go!
The OP asked for visual differences in the head design ...
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From: soooooCA
Re: (FullEP3)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FullEP3 »</TD></TR><TR><TD CLASS="quote">
I'm with inkong ... the A3 head doesn't suck ... the K20A3 makes good power for what it is ... very usable and it has one of the flatest torque curves I've seen. I've had zero complaints running this motor on the track ... just take some weight out of the EP3 and you're good to go!
The OP asked for visual differences in the head design ... </TD></TR></TABLE>
Good info on this thread
Weight reduction is a must for the EP
I'm with inkong ... the A3 head doesn't suck ... the K20A3 makes good power for what it is ... very usable and it has one of the flatest torque curves I've seen. I've had zero complaints running this motor on the track ... just take some weight out of the EP3 and you're good to go!
The OP asked for visual differences in the head design ... </TD></TR></TABLE>
Good info on this thread
Weight reduction is a must for the EP
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Re: (inkong)
curb weight from the factory is 2782lbs ... last time I had the car scaled it was down to 2575 without driver. There is still room for more weight to be removed ... Grassroots Motorsports had an 02 EP3 project car ... prep'd it for racing ... check out the article. Good read ... enjoy!
http://grassrootsmotorsports.c...ic-si/
http://grassrootsmotorsports.c...ic-si/
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My bad on the whole 3 lobes on the intake cam of the a3. But anyway everyone that downs the a3 head has no idea what they are talking about. I just get irritated that people think because the a2 has I-VTEC on both cams it's so much better. I love my a3 and i'll show you why!
Here is why!
Here is why!
