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Kewhl!

But keeping the valves open at low RPM and setting up the ECU for high cam would probably suck gas.

Do I really need low end torque? I have an IMA. I'd rather have more high end and keep the low end stock so it wouldn't eat gas in daily driving.
 

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Its a VTEC killer cam - there is no VTEC because the car is basically always in VTEC. with these cams the car should also rev a bit higher due to the tune on the spoon ECU. The Video Bulletproof posted about the Spoon CR-Z a few days ago said their car with built motor gets 25 and 29 mpg. It wasnt clear if the only mods were cams and a tune though
 

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With spoon venturi throttle body and a good intake, mpg is not affected, however, with the high cam shaft kit, mpg will be lower over long distance.
the best thing to do would be to change only the programmatopn of ecu to have more rpm and more fuel over 4000 rpm, then long distance mpg would be the same, and when you need power you will have more, only WHEN needed. The included ECU does that, but with one closed intake valve this is not the same program.

This is NOT a vtec killer, this is a valve opener, since vtec is still there, vtec modifies still the TIMING at high rpm.

This mod only insure that you have 16 valve all the time. The two cams have a shifted angle, so vtec is still there. Maybe the shape of the high rpm cam is a little more agressive, but i don't know.
 

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With spoon venturi throttle body and a good intake, mpg is not affected, however, with the high cam shaft kit, mpg will be lower over long distance.
the best thing to do would be to change only the programmatopn of ecu to have more rpm and more fuel over 4000 rpm, then long distance mpg would be the same, and when you need power you will have more, only WHEN needed. The included ECU does that, but with one closed intake valve this is not the same program.

This is NOT a vtec killer, this is a valve opener, since vtec is still there, vtec modifies still the TIMING at high rpm.


This mod only insure that you have 16 valve all the time. The two cams have a shifted angle, so vtec is still there. Maybe the shape of the high rpm cam is a little more agressive, but i don't know.
What?

heres some iVTEC info: "i-VTEC regulates the opening of air-fuel intake valves and exhaust valves in accordance with engine speeds

By regulating valve opening to match engine speed, the agile i-VTEC engine adjusts its characteristics to realize both superior power and low fuel consumption."

iVTEC kicks on in the CRZ the opposite way normal VTEC does. Only until you are in a constant cruising mode does iVTEC kick in and go to the economy "low" cam. The Spoon cam eliminates this low cam switchover so the whole time you are in high cam performance mode... The spoon cams are VTEC killers in this sense. Someone correct me if im wrong, thats my understanding

EDIT: http://world.honda.com/automobile-technology/i-VTEC/ (for more information)
 

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Hum Good to know! so you think they have made 2 Ecu one for the cam and one just to raide RPM?
the one included with this kit is tuned for the spoon cam. they have not released another ECU that can tune for a raised limiter and for fuel. One of the piggybacks may work (like AEM) or you will have to wait for Hondata (or wait for more info on HKS f-con)
 

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@northbridge i have to fix something that is not well understood, and sorry for my poor english.

VTEC is variable TIMING and DEPTH of opening valves by the use of two cams per cylinder instead of one, and a lever swich to the second one at high rpm. GE8 engine is vtec, there is still 8 cams, angles and shapes of cams are different so it is still a vtec.

iVTEC added VTC and VTC don't need to close an intake valve to work but this make it more simple. VTC is just an action on the angle of the camshaft all together, and there again the VTC is not killed by this mod.

the iVTEC multiples systems and ideas are all aimed at one target : widen the useable zone of the engine, in a smarter way than turbos, or compressors, without adding friction.

This mod may use more fuel, but it is not required. (at higher rpm, yes it will put more fuel)

Honda choose to close one intake valve at low rpm to let the electric part do most of the job in this zone, but with careful tuning it is possible to achieve the same fuel economy with full time 4 valves, maybe gaining in the process some low end torque.

But i am pretty sure the work of spoon is also toward the high rev, the high cam, will make the engine more race-like above 4500rpm.

VTC control is ONLY MADE BY ECU.

this mod take our state of the art iVTEC and make it ULTIMATE iVTEC anti-turbo engine.

EDIT : and don't forget that the benefit of 3 stage vtec is also included in our engine, this is action on the lever by oil pressure, and vtc by ecu, depending on the throttle pedal fully depressed, ie ability to switch to high value VTC and cams on-demand instead of rev value only. All those systems make a true 3D space variable geometry engine.
 

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ok, i just read all of that. great info but im not sure i still understand whats going on with the spoon kit. as far as I understood the L motor in the ZF1 has iVTEC the same way as the R18 Civic:

The new DBW (Drive By Wire) system on the R18A now constitutes a major and crucial part of the R18A's SOHC i-VTEC mechanism. Firstly, it provides the high-precision control over the throttle valve required while the valve timing is being changed over, ensuring smooth driving performance that leaves the driver unaware of any torque fluctuations. Secondly, and more importantly, during the economy mode there is the unusual, and conflicting situation where while the throttle pedal is at an almost completely closed position, the throttle butterfly in the throttle body is in an almost completely opened position, the exact opposite ! However, this relationship only applies when the engine is running in economy mode, when VTEC has activated the fuel economy cam lobes. In normal running, the normal relationship between throttle pedal position and throttle butterfly opening remains, i.e. light throttle means small throttle butterfly opening, etc. Thus the SOHC i-VTEC mechanism used in the R18A is only possible with a DBW system.

So the new SOHC i-VTEC implementation is an entirely new implementation, quite unlike those already in use. Under normal driving conditions, the R18A runs on its normal set of cam-lobes which in a completely reversed role, Honda calls the 'hot-cams'. So VTEC-off on the R18A means it can be considered to be running high cams. When the right conditions are acheived for fuel economy, VTEC engages the 2nd set, the 'low' or 'economy' cams. Thus VTEC-on on the R18A means it is running low cams. More importantly is VTEC engages the low-cams only if the right conditions for fuel economy are acheived. If they are never acheived, like when we are driving aggressively for the whole trip for e.g., VTEC will never open on the R18A. Thus it is a completely different idea from the VTEC implementations of old where VTEC will always open after a certain rpm, irregardless of the driving conditions. This is also the reason why Honda feels it is justified to call this new implementation an i-VTEC implementation, 'i' of course meaning 'intelligent'. This is because the engine/ECU is 'smart' enough to know if conditions are right or not for VTEC to engage. This new mode of operating is clearly illustrated in the 3-dimensional torque-rpm-driving load chart on the left (supplied by Honda). Note the standard torque curve. This is the line right at the top of the chart and VTEC never activates across this torque curve. On the other hand, VTEC opens across a fairly wide range of driving conditions, in the shaded portion inside the torque curve. So if our throttle pedal position or other critical driving conditions are outside the shaded portion, the R18A will not engage VTEC at all
If this is the case, going into VTEC means switching to the low cam for fuel efficiency while being out of VTEC means the motor runs on High cam for power. If the CR-Z is like this then the VTEC switchover changes the motor profile from 16valve to 12 valves. The Spoon cam kit would replace the intake cam and never allow the motor to jump down to efficiency mode at 12 valves. By doing this the engine would stay in performance mode with the full 16 valves open and there would be no VTEC switchover, hence VTEC killer.

human or anyone else with knowledge care to chip in here?
 

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It replaces the crz camshaft by a ge8 fit camshaft meaning the economic mode does not close an intake valve but opens both by less depth. 2nd feature is the power mode starting from 120 hp base (ge8) using VTC and a higher rpm to go up to 147hp.

Opening a valve is a lot more than a yes/no binary operation: it is variable in when it begins (VTC) how long and how much depth (cam shape) an even then there is variable quantity of air/fuel mix injected.

When gong down a slope fuel is not injected at all but engine stays in high cam to reduce friction ant to exchange air freely.
 

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Spoon recommended to run the cams with fuel management so you will not get what you expected with these cams without tuning !
 
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