stupid ? for you

D15, D16, D17 and Mini-Me swaps
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By chrono404
- Sun Feb 24, 2008 9:07 pm #43645 You Still dont get it. It doesn't matter if it doesn't have a VTEC-E Valve Cover. Your Head came from a Civic HX. Which has the VTEC-E Engine. Therefore in Your Possession, You have a VTEC-E Head. This is Mechanically Different From a Vtec Head which has Performance Vtec.

Vtec-E under low operation, using only 2 valves per cylinder. When Vtec-E Engages it uses 4 valves per cylinder. Still following normal cam operation.
Vtec uses all 4 valves per cylinder, When Vtec Engages you go to a More Extreme Cam Setting. See the Video I linked to above, It will show Performance Vtec in Action.

If you want to do a Mini-Me Swap you will want to get a D16z6 or a D16y8 Head. This will have the Performance Vtec, Which is what you want. For What you Want to do, You Do Not, I repeat, You DO NOT want to use the HX Vtec-E Head.

You will want to pay attention to all the Bold Parts. This answer all the Questions you have asked.
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By BAXTER_EJ1
- Mon Feb 25, 2008 2:01 am #43654 IMO you can do everything that guy did, but you're still limiting yourself by going with the VTEC-E as opposed to the VTEC.

What he's doing is RESEARCH and figuring out if he can make that work, is that what you want to do? :?
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By kmarshall3
- Mon Feb 25, 2008 2:36 am #43655 This thread's amusing...

Just buy the non-vtec head that i have sitting in my floor with a stage 2 cam! I don't need it and I need money 8)
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By chrono404
- Mon Feb 25, 2008 4:07 am #43660
BAXTER_EJ1 wrote:What he's doing is RESEARCH and figuring out if he can make that work, is that what you want to do? :?

x2

We have already given you our input. Nothing else we say will change your Mind.

If you choose to go do this, Then go ahead. However Doing so will deliver less power for the money you spend down the Road.
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By teal_dx
- Wed Feb 27, 2008 11:43 pm #43934 I didn't read all 30+ pages but what what you're talking about HAS been done successfully. The HX engine is designed with economy in mind and boasts more low-mid range power & torque than top end. The P2N (manual) and P2M (automatic - CVT) ecu that is programmed to control this head is OBD2. The HX operates with 4 valves, and then goes into lean burn mode 3 valve (1 intake, 2 exhaust) when the conditions are right. For example when cruising @ 55mph, not using very much pedal.
VTEC-E actually gives you LESS power when it kicks in vs VTEC which switches over to more aggressive intake lobes on the cam (on SOHC's)

The HX head uses roller rocker lifters = good

There's no aftermarket support for the HX head = bad

The person who did this swap ended up with a successful result, but it took a lot more time and money than if they just did a z6 or y8 head. I remember someone using an HX head made almost as much torque as it did HP, it was a different thread I read a long time ago on H-T.


If you have the time/money then give it a shot. I like to see people try things out of the norm :thumb:
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By darkshadow
- Thu Feb 28, 2008 2:17 am #43975 i think i will try it, i will also be buying a z6 head, i can get one for 100bucks from someone, and build it up!
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By bietelboer
- Sun Mar 09, 2008 7:50 pm #45574 If you have the option, then use the d16Z6 head!

If you still want to use the vtec-e head then you can put the D16Z6 cam and bridge in the vtec-e head(d15z6).

Over here in Holland we have a few Vtec-e's (d15z6) that put out 150 hp 8)
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By darkshadow
- Sun Mar 09, 2008 7:54 pm #45575 i would be able to swap the cam's?hmm i might have to do that!
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By bietelboer
- Sun Mar 09, 2008 7:59 pm #45576 You really need to do A LOT of research, when you dicide to swap the cam...
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By suspendedHatch
- Sun Mar 09, 2008 10:45 pm #45597 Let me give this a shot to see if I can help.

VTEC-E is a mechanism that switches between 12 and 16 valves at about 2500 RPM.

VTEC is a mechanism that switches from normal cam lobes to more aggressive cam lobes at about 5000 RPM.

They are fundamentally different. The only similarity is the mechanism that switches it on and off. But that's like saying a lamp and a tv are the same because they both have power buttons.

The actual change in breathing that VTEC and VTEC-E imparts on the motor is built into the VALVETRAIN, not the ECU, and not the VTEC solenoid (which is interchangeable between the Z1 and Z6, and interchangeable between the Y5 and the Y8 ). (The valve covers are also interchangeable between the Z1, Z6, Y5, and Y8. Changing the valve cover changes nothing.)

The ECU sends a signal to power the VTEC solenoid, at the same time altering the fuel injector pulse width and ignition timing advance. The VTEC solenoid fills with oil pushing a pin locking the intake cam followers together. This is the same in principle between the VTEC and VTEC-E heads. But the difference is in the cam.

In the case of the Z1, the intake manifold, combustion chamber, throttle body, and ports are all smaller than the Z6 (smaller in fact than the DX motor). You are correct in saying that the intake manifold, combustion chamber, throttle body, and ports on the Y5 are all the same as the Y8, but the Y8 has a different cam, no roller rockers, and no EGR. And the cam is what makes the difference between 105hp and a 130hp.

Switching VTEC-E on at a later RPM doesn't transform it into VTEC. It will not benefit you in any way, in fact, it will kill your power. If you want to put a P28 on a VTEC-E head and pretend like it's going to transform it to VTEC, what will happen is that the motor will now stay in 12 valve mode until 5000 RPM and then switch to 16 valve mode. Further, a P28 calibration is designed for an OBD1 engine. But the combustion chamber is drastically different between the Z6 and Y8/Y5 engines. Namely, the Y8/Y5 can handle more timing advance (which in turn affects the afr). So running the incorrect ECU for the application will always cost you in power and mileage. Maybe it will even run good, but it wont be as good as stock. Even if you run a P28 chipped with a Y8 calibration on a Y8 head, are you going to wire up the knock sensor? BTW the Y5 calibration is unavailable so that's not even an option.

I recently dyno tuned my engine (D15B 3 Stage VTEC, AEM EMS), I remember doing an initial dyno pull with both VTEC-E and VTEC turned off. Basically it ran on 12 valves the whole pull. Power COMPLETELY fell off the dyno chart somewhere around 4000 RPM. I made 60hp. Can you see the problem of trying to run the Y5 head with a P28?

The end result of my tuning netted 119hp and 99ft/lbs on a stock internals, I/H/E motor.
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By suspendedHatch
- Sun Mar 09, 2008 11:07 pm #45599
teal_dx wrote:VTEC-E actually gives you LESS power when it kicks in vs VTEC which switches over to more aggressive intake lobes on the cam (on SOHC's)


I want to over-clarify this because initially my brain rebels at this statement.

The VTEC solenoid found on the SOHC VTEC and VTEC-E motors of the same OBD generation is the exact same part. It operates the same. It's normally OFF and is switched on by the ECU when throttle, load, and RPM conditions are met (with some safety checks on coolant temp and oil pressure).

When you talk about VTEC-E, you have to decide what it is. Is it 12 valve mode or 16 valve mode? I think most people agree that it's 12 valve mode. So what that means is that when the VTEC solenoid is OFF, you're in 12 valve mode, or VTEC-E mode. At 2500 RPM the VTEC solenoid turns ON and you run 16 valve mode.

VTEC-E doesn't kick in at 2500 RPM, it kicks OFF.

The car leaves a stop in 12 valve mode. The car idles on 12 valves and stays in VTEC-E until you give it sufficient throttle and it reaches a sufficient RPM, then it goes into 16 valve mode until throttle and load fall below a certain point (light cruising), then it switches the VTEC solenoid OFF again putting you back into 12 valve mode (VTEC-E mode). Less air requires less fuel (which is desirable when cruising) resulting in less power. When you start climbing a hill, first load increases, then throttle (if the driver is awake), so the ECU switches back to 16 valve mode giving you more power.
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