SlowCar

iTrader: (4)

Pros and cons? Chime in

Richard L

iTrader: (5)

I think there is a market for both systems.


on/off system:
pro:
1) Predictable and quiet easy to tune - (within a narrow band).
2) system design is simple, cost is low.

con:
1) Work well only on a narrow band.
2) Need to take a large chunk of afr near the max torque area - make the engine more prone to damage if water runs out.


Progressive system:
pro:
1) Wider range of operation
2) System design is more complex, cost is higher.

con:
1) "progressive" has to be well defined - with air mass, manifold pressure, rpm or fuel delivery or all? More questions has be asked about the merit of each method.
2) Ease of tuning will depend on the above methods.
3) System will increase in complexity - if it has to respone to engine operation dynamics. If the progressive system cannot response fast enough, there is no point being progressive - possible to tune on a dyno but will behave differently on road or race conditions. Don't forget most tunes are done on 4th gear.


Richard

SaabTuner

D'oh! I just posted a response which would have gone better here in the other long thread on WI and alky.

edit, linky: https://www.evolutionm.net/forums/sh...&postcount=195

C6C6CH3vo

iTrader: (9)

Stupid question here:

The SMC kit sprays a constant amount, ml/min and psi, throughout the boost and rpms, right? I assume this is what is meant by on/off.

I know simple question, but I want to make sure.

GTVEVO

iTrader: (22)

The Buschur/SMC and the AMS/Alky Control kits are both Progressive kits. They both ramp up with a start pressure and a max pressure so as boost increases so does the level of fluid by the pump pressure going up. I would choose a progressive kit over a On/Off kit. With a progressive kit it can still be used as a On/Off also by using the gain with the pump start and stop set the same so you get the best of both worlds. That really leave no reason for choice.

Richard L

iTrader: (5)

There are many ways to define a progressive system.
Question. Progressive with what?

Here is some of my definition:

1) On/off system can be also called progressive:
Boost pressure increases - the flow decreases due to back pressure
RPM increase - flow decrease relatively due to mass air increase.

2) Pump speed control based on manifold pressure:
progressive with boost but not with RPM. Better but not ideal.

3) Pump speed control based on MAF:
progressive with overall air flow - ideal

4) Pump speed control limitations:
Rarely achieves more than 2x flow range - because pressure change has to be 4x. If the startup pressure is 60 psi, you only get twice amount of flow at final pressure of 240psi. Some pump (due to large rotating mass - inertia), the flow may not cope with fast throttle change (mass air flow change).

5) Inline PWM valve control:
Good compromisation overall performance, I wonder why there isn't more WI manufacturers on the market making this type of system. It makes sense and almost 99% of the Fuel Injection systems on the market uses this method.


Richard

C6C6CH3vo

iTrader: (9)

I've been looking at the Snow Product, It appears simple and robust. Thier Evo setup uses the MAF progressive type. They also have a seperate failsafe system the routes 12vdc to a WG solenoid. I have'nt noticed the type of pump used but I did see "50psi" printed in the lit, but I'm not sure in what context.

So far for me it's between the above setup, or SMC with either the SMC, Snow, or even DDS3 failsafe - whichever is fast, reliable and simple. The benifit with SMC would be the ease, experience, and record my tuner of choice has with it.

If I could have any system I wanted it would be the Aquamist/Shureflow, but I dont have the tools, budget (I need a 3rd part-time employer), and knowlege for that. Who knows, I have plenty of time.

Richard L

iTrader: (5)

The two systems (SMC and Snow) have similar capabilities and cost, it will be between MAF or MAP. I am sure the SMC system can read MAF since both sensors give 0-5V output against load.

Since you have a limited budget, talk to SMC and ask if they can read MAF since it will give you a better correlation between alcohol and charge mass flow.

I am not an experienced with the "ease of tuning" on either system, perhaps some one else who had some feedback from their tuners can chime in.

Richard

djmikeymike

iTrader: (1)

great info!!

Rocket468

Richard L so your saying pwm is good. I bought a devilsown and in your other post you said its a pwm. I was told it usually is ran off a map but on my car i should run it on my maff. He did not know what color wire i should tap into. Which is right wire? sorry for the stupid questions i just don't want to mess my car up.

Richard L

iTrader: (5)

There are two basic types of PWM:

1) PWM drives a water pump to vary its speed to increase flow but the range is limited to 2x flow generally.

2) PWM drives an inline valve to meter flow. It is easily mappable and have a wider dynamic range at constant pressure.

I may have made a mistake about the MAP sensor and MAF sensor. Most MAF gives out 0-5V analogue voltage and can be fed into the Devils own controller.

But I think the EVO's MAF has a frequency based output and it is not suitable to work with a analogue PWM WI controller. Please check with Devilsown before installation.

Richard

SlowCar

iTrader: (4)

bump

good comparison info from a long time ago

C6C6CH3vo

iTrader: (9)

Are the high speed valves contollable outside the IDC range through RPM? If so then why not look in to a patch for ECUFlash that can run the HSV that will run any value you like at any rpm vs load

Ultimate CC

iTrader: (122)

great idea...i love the what ecuflash gives this community...endless possibilities...

C6C6CH3vo

iTrader: (9)

It would be difficult though, need a controller that would somehow respond to an ecu output. Maybe in a couple years