CPS (Cam Profile Switching) vs VVTI vs DVVT

[estear]

Well, I own an Exora manual, and I must say I still sometimes get a 'torque dip' when going up a rather steep ramp on 2nd gear that forces me to do a complete stop, apply handbrake & rev up on 1st. Now this engine as I understand is a drive-by-wire (at times, the engine still revs up a for a short while when I release the gas pedal & press the clutch pedal).
Garret actually has developed what they call 'ebooster' to electrically provide turbo engine boost at lower revs until the actual turbo charger kicks in...
I guess it boils down to how much do you need & when do you need it...I can't imagine Exoras being turned into speed demons, so as far as Campro Turbo is concerned there may not be a one size fits all solution...

 

[GSR06]

Well, I own an Exora manual, and I must say I still sometimes get a 'torque dip' when going up a rather steep ramp on 2nd gear that forces me to do a complete stop, apply handbrake & rev up on 1st. Now this engine as I understand is a drive-by-wire (at times, the engine still revs up a for a short while when I release the gas pedal & press the clutch pedal).
Garret actually has developed what they call 'ebooster' to electrically provide turbo engine boost at lower revs until the actual turbo charger kicks in...
I guess it boils down to how much do you need & when do you need it...I can't imagine Exoras being turned into speed demons, so as far as Campro Turbo is concerned there may not be a one size fits all solution...

Thanks for sharing. How much is Exora's FC assuming you are driving in city as well as on the highway? In terms of responsiveness, VVTI is still a better choice as I have personally experienced it...the Vios J series is quite a powerful car, especially on the highway.

About the Garret, I haven't heard about it but since many years ago in the US, there was one device that I knew of that would keep the boost at 1.0bar. Not sure whether this is the same thing that we are talking about. Usually, the turbo will only kick-in past 3000rpm.. and for Campro Turbo, I don't think they are going to put in a TD04 as a minimum, maybe something like a TD.025 or smaller like the ones used by the Volvo or mercedez. Reliability is still the main concern here.

 

[boyzone]

Btw, low boost turbo ( <0.5 bar ) should not a problem for realibility.

 

[estear]

Mine is still not past 1st 1000 km yet so may not be a good reference, the manual says should reach optimum after 3000 km. But others on average is on the 10 l/100 km and a bit for AT.
Having said that, it is rumored (haven't gotten any confirmation from Proton yet) that the Campro CPS for the Indonesian market is tuned for RON88 similar to other locally assembled cars, so don't really know how it will affect the whole performance of the Campro CPS. On highways, it runs smoothly, when I turn on the IFC (instantaneous fuel consumption) display, I can get around 5 l/100 km @ constant 90 km/h with light pressure on the gas pedal. After all it is an MPV. But on average, I can realistically expect 10 l/100km.
If I'm not mistaken, Vios' VVT-I is continuous, not 2 stage like CPS or VTEC so understandably, VVT-I is a more superior technology.

 

[GSR06]

Btw, low boost turbo ( <0.5 bar ) should not a problem for realibility.

I agree and it actually depends on the driver as well. Performance @0.5bar vs 1.0bar, is so much diffferent. Agree?

 

[LittleWhiteWagon]

Lag also... but I find it fun

 

[GSR06]

Lag also... but I find it fun

Lagging issue will always exist but when the turbo starts to kick-in, it feels really great...

---------- Post added at 07:24 AM ---------- 6 hour anti-bump limit - Previous post was at 07:20 AM ----------

Mine is still not past 1st 1000 km yet so may not be a good reference, the manual says should reach optimum after 3000 km. But others on average is on the 10 l/100 km and a bit for AT.
Having said that, it is rumored (haven't gotten any confirmation from Proton yet) that the Campro CPS for the Indonesian market is tuned for RON88 similar to other locally assembled cars, so don't really know how it will affect the whole performance of the Campro CPS. On highways, it runs smoothly, when I turn on the IFC (instantaneous fuel consumption) display, I can get around 5 l/100 km @ constant 90 km/h with light pressure on the gas pedal. After all it is an MPV. But on average, I can realistically expect 10 l/100km.
If I'm not mistaken, Vios' VVT-I is continuous, not 2 stage like CPS or VTEC so understandably, VVT-I is a more superior technology.

So, yours is still a new car on the road :proud:. Maybe after your 1st service, things will change for better or for worst. Pls share with us then later on....

Comparing all, VTEC is still the best in my opinion...

 

[estear]

Lagging issue will always exist but when the turbo starts to kick-in, it feels really great...

---------- Post added at 07:24 AM ---------- 6 hour anti-bump limit - Previous post was at 07:20 AM ----------



So, yours is still a new car on the road :proud:. Maybe after your 1st service, things will change for better or for worst. Pls share with us then later on....

Comparing all, VTEC is still the best in my opinion...

I will...actually, CPS works similarly to VTEC. CPS does it on tappets, no rocker arm, whilst VTEC works on the rocker arm...basically switching between 2 cam profiles one for high revs and another low revs...

 

[boyzone]

Those 2 stage cam engines are designed with same goal.
Different in name and operate function is due to copy right issue.

 

[GSR06]

I will...actually, CPS works similarly to VTEC. CPS does it on tappets, no rocker arm, whilst VTEC works on the rocker arm...basically switching between 2 cam profiles one for high revs and another low revs...

High revs...anything above 8k is good? I have not tried until that level yet. Talking about the naming, which sounds the best...in your opinion?

---------- Post added at 02:39 PM ---------- 6 hour anti-bump limit - Previous post was at 02:38 PM ----------

Those 2 stage cam engines are designed with same goal.
Different in name and operate function is due to copy right issue.

functions the same but the output is so much different la...how come?

 

[tigger5251]

Dyno chart of CPS (from PaulTan's bloggie)

---------- Post added at 02:59 PM ---------- 6 hour anti-bump limit - Previous post was at 02:58 PM ----------

109whp at 6422rpm........

BUT

129nm wtq at 4763rpm

SLUGGISH!

 

[estear]

Actually, I found something interesting. The same technologies used for Proton's engine (CPS & VIM) is also used on the LR-V8 engine for 2010 Range Rover, Range Rover Sport and Discovery 4/ LR4 (watch the video here: YouTube- Range Rover and Land Rover 2010 New LR-V8 Petrol NA Animation) and also on Jaguar's AJ-V8 engine.
So the difference may not lie on the technology itself, but perhaps more on who manufactures them...

 

[boyzone]

---------- Post added at 02:39 PM ---------- 6 hour anti-bump limit - Previous post was at 02:38 PM ----------



functions the same but the output is so much different la...how come?

This is because of :
-CPS is mainly focus on low and mid range RPM.
-Euro 4 emission control.

 

[tigger5251]

Firstly, VTEC uses high revolution and short ratio gearbox to compensate the peak torque at 5000-600rpm, and VTEC revs untill 9000rpm

And for this Range Rover engine, its a V8 ! Do you know how much torque a V8 generates?

Both these different agendas has their own conpensation to counter back the VIM technology drawbacks, which were well matched and designed by their RND team...

But CPS, consumers are the RnD white mouse......hehe

 

[LittleWhiteWagon]

Dont forget honda has YEARS of experience in motorsport + making motorbikes.

Proton... theyve got years of selling 12v mitsubishi engines

You all unfair lah compare, hahahaha

 

[tigger5251]

We all should know what is Proton, shouldnt expect much from it.....

 

[GSR06]

Firstly, VTEC uses high revolution and short ratio gearbox to compensate the peak torque at 5000-600rpm, and VTEC revs untill 9000rpm

And for this Range Rover engine, its a V8 ! Do you know how much torque a V8 generates?

Both these different agendas has their own conpensation to counter back the VIM technology drawbacks, which were well matched and designed by their RND team...

But CPS, consumers are the RnD white mouse......hehe

VTEC is more for performance whereas our own CPS is more for driving pleasure...so far, not much issue on CPS engine...maybe because of low torque and low power....

 

[estear]

I may be wrong, but I imagine it's the cam profile & phasing (= valve overlap) that affect engine characteristics? That's why there are many such technologies to optimize engine performance such as CPS, MiVEC, VTEC/i-VTEC, VVT/VVT-i/DVVT, Vanos, etc.

 

[Erik Yong]

Hi,
Yes, I have tried the top speed. Cps needs a very long empty road. VVti , no peoblem!
The manual version is better in terms of response and feul consumption. Yes, I have driven one too. I think the poor response from the cps stems from the basic campro engine itself. I remember first trying the neo auto when it first came out and was terribly dissapointed with the dud engine. I thought the handbrake was on! The sales person told me to step on it! By adding the Cps, it has helped.. otherwise I would not have bought the car. Just don't expect anything from it and enjoy the handling to a certain degree.

Regards,

Erik

 

[GSR06]

Hi,
Yes, I have tried the top speed. Cps needs a very long empty road. VVti , no peoblem!
The manual version is better in terms of response and feul consumption. Yes, I have driven one too. I think the poor response from the cps stems from the basic campro engine itself. I remember first trying the neo auto when it first came out and was terribly dissapointed with the dud engine. I thought the handbrake was on! The sales person told me to step on it! By adding the Cps, it has helped.. otherwise I would not have bought the car. Just don't expect anything from it and enjoy the handling to a certain degree.

Regards,

Erik

Hehe, you are right...when you try to build up the momentum and suddenly there is one car in front of you and you have to brake, guess what, you have to build up the momentum again...this really sucks man. Anyway, this is the reality but this problem could be overcome with a B.O.T. or with Quadcam or etc..

---------- Post added at 07:56 AM ---------- 6 hour anti-bump limit - Previous post was at 07:49 AM ----------

I may be wrong, but I imagine it's the cam profile & phasing (= valve overlap) that affect engine characteristics? That's why there are many such technologies to optimize engine performance such as CPS, MiVEC, VTEC/i-VTEC, VVT/VVT-i/DVVT, Vanos, etc.

Maybe, it could be compensated by changing the ECU, adjustable CAM pulley, exhaust system, BOT, etc. Perhaps a boxer or rotary engine for performance enhancement purpose. Comparing original setup, CPS is still far far behind la....