Spoon High Cam Conversion Kit

[AJR Jay]

Hey Everyone!

Introducing the Spoon High Cam Conversion Kit for the Honda CRZ!

As many of you have probably seen already, Spoon had introduced a high cam conversion kit for the CRZ.

We're here to give everyone a little insight the kit itself. As most of the posts online have insufficient information.

How the LEA camshaft works ?
The way the CRZ's Vtec system works is slightly different than that of any other Honda. Instead of running 2 different camshaft intake lobes, the CRZ only has a single lobe initiated at all times regardless if the car has engaged Vtec or not. The way Honda designed it, the low end is assisted by the electric motor for fuel economy.




CRZ Camshaft shown above.

During low RPM, the CRZ's intake cam only opens 1 intake valve. The other intake valve remains dormant and does not open. Once Vtec engages on the car, the rocker arm locks and the single cam on the CRZ actually opens both intake valves on the car.

Generally, what Spoon had decided to do was use the Honda Fit GE8 camshaft mechanism on the CRZ. You'll notice that the intake lobe lift on the CRZ is lower than that of the Fit GE8. Not only that, but the Honda Fit also has a second intake lobe.

How Spoon camshaft works ?
Now the Honda Fit GE8's Vtec mechanism works completely different than that of the CRZ. Instead of having intake 1 lobe control the intake valve or valves at all times, both the GE8's intake lobes are initiated when Vtec is not engaged. However, once Vtec is engaged on a GE8, the rocker arms lock and only the higher duration cam lobe is used to open both intake valves.




Spoon High Cam Conversion Kit shown above.

Now with this observation, it is evident to see why changing the camshaft on the CRZ to the Fit GE8 will provide such a larger gain in performance when intake volume is increased. Not only is the lift duration on the GE8 longer than that of the CRZ (1mm higher lift), but the fact that you have both valves opening before and during Vtec will greatly increase the performance on the CRZ.

Tuning :
Spoon also provides an ECU with their high lift camshaft kit. Please note however, we have tested that the Spoon ECU is NOT compatible with EDM or USDM vehicles. ECU upgrade is required so our best bet will be Hondata Flash Pro. We are expecting to see about 12-15whp.

Finally, for best results, Spoon also recommends replacing the stock throttle body to their big venturi throttle as well along with this kit.

The Spoon High Cam Conversion Kit is available and we are working closely with Spoon on this.

If you have any other questions or concerns, feel free to ask.

Thanks.

Jason @ AJR

[Tbot]

Sexy! I want!

[hotboxn]

Thank you for posting this. It's nice to know how this will change and that we'd also need the Hondata unit.

[B-rad]

So your using the ge8 can instead of the crz one? I thought this has been out for awhile?

[InsightRacer]

Not to start a flame war (and hopefully to help us all understand better), but some parts of the article are not exactly correct.

The real point of the post is completely correct: Spoon has a camshaft kit based on the Fit GE8 that offers better breathing and more power.

AJR Jay is right that "CRZ's Vtec system works is slightly different than that of any other Honda" (at least, all that I am familiar with). However, the description of the way the CR-Z (LEA) valvetrain works is not completely correct.

There is, in fact, one lobe on the camshaft for each valve. You can see it in the first picture (4 lobes between each journal). The valvetrain below it also shows a rocker arm for each value. Each of these rocker arms operates independently and rides its own cam lobe in low VTEC (VTEC off).

You will note that the lobe size of the two inner (intake) lobes (in each set of 4) is different. The one on the right (primary) has lift and the one on the left (secondary) appears to have no lift. This gives the effect of a single intake valve opening, creating swirl in the cylinder which is good for gas milage at low RPM. However, if you look closely at the secondary lobe, you will notice wear marks (particularly in the 2nd and 4th lobe sets (from the left) in the picture). This shows there is a small amount of lift. Honda designed it this way to prevent fuel puddling in a closed intake port.

In high VTEC (VTEC on), a piston in the two intake rockers locks them together. As a result, both valves open based on the highest lobe (the primary). This gives more airflow at higher RPMs for performance. The exhaust valves don't have VTEC and operate the same way all the time.

This may seem complicated, but it is one of the simplest VTEC mechanisms that I have seen on a Honda and is very effective at providing two different cam profiles without a lot of parts. Everything is controlled by the cam lobe size. In theory, you could get cams with bigger lobes and get a similar effect of the GE8 mechanism. But it is probably not that simple. The valvetrain has to have the clearance (and the right springs) for additional valve lift and the LEA valvetrain may not have this.

I don't know exactly how the GE8 mechanizm works, but it is clearly different as you can see in the pictures. The intake valves seems to somehow connect to each other (probaby some other mechanism to lock them together at high speed). And the real point is the cam lobes are higher providing more airflow.

Hope this makes things clear.

[AJ PwR]

Originally Posted by B-rad

So your using the ge8 can instead of the crz one? I thought this has been out for awhile?

Yes it has been out for awhile but no one really test and have full understanding about the part.

InsightRacer, thanks for the input.

Jay is not 100% correct but in regards to the CRZ cam lobes, it actually have 3 (one intake and two exhausts). One of the journals on the CRZ camshaft is missing. When the VTEC is OFF, basically one valve opens and vtec kicks in then it opens the other valve.

The GE8 camshaft has 4 lobes instead of 3 plus it has primary and secondary so it will open the valves during VTEC ON/OFF.

Furthermore, the entire rocker arm assembly has to be replaced if you run the GE8 camshaft because of the extra roller on the rockers for the cam in order it will work properly.

According to what Spoon told us, the spring rates of ther CRZ camshaft is strong enough to run the GE8 cams with no issue.

[Old School]

So there is no tune available for US cars? This means if we buy this kit, we are on our own for getting it tuned. Does this mean we get the kit at a cheaper price since we don't need/can't use the tune Spoon normally provides? Are you currently attempting to tune this cam with a Hondata unit? If so, when do you think you will have results?

[SuiteMike]

Can we get an estimate price for this?

[AJ PwR]

Originally Posted by Old School

So there is no tune available for US cars? This means if we buy this kit, we are on our own for getting it tuned. Does this mean we get the kit at a cheaper price since we don't need/can't use the tune Spoon normally provides? Are you currently attempting to tune this cam with a Hondata unit? If so, when do you think you will have results?

Yes, there's NO TUNE available.

The price will be adjusted and we are working closely with Spoon to work out the final pricing without the ECU.

We have plans to replace the camshaft on our AJR CRZ and wil keep you guys updated

[Old School]

Originally Posted by AJ PwR

Yes, there's NO TUNE available.

The price will be adjusted and we are working closely with Spoon to work out the final pricing without the ECU.

We have plans to replace the camshaft on our AJR CRZ and wil keep you guys updated

Great to hear!