[v1p3r]

Also, can someone define batch, semi-sequential, and sequential, wrt injectors?

[rdkarthik]

Originally Posted by Rehaan

I think what ananth is saying is, he wants to concentrate only on the electronics in this thread. The only reason he has mentioned mechanicals like Cam profile, CR etc is to give a basic starting place to build the electronics upon.



RDK,

Can you give us an idea of which indian cars (engines) have just CKP and no CMP and which engines have both.
Also are there any engines which have CMP and no CKP ?

Is it feasible to install a CMP to a head which came without it as OEM ?

cya
R

Rehaan,

Cars with just CMP - Estem,zen, ohc (in a way, as readings are refernced from cam) ...

Adv- Its simpler to implement these systems and costs lesser..

Disadv - Not extremely accurate for precise ignition control


Cars with both - Baleno, Accents, wagon Rs, etc.

Adv- Very accurate control of igniton timing, more reliable

Dis adv- Expensive.


I am not aware of cars having just a CKP ( maybe the escort 1.6 zetec) ... Also note that CMP signals in CMP only cars are different from those that have CMP and CKP.

For a head that did not have a CMP its simpler and better to install a CKP sensor. You can do batch and semi-sequential injection, but not sequential injection with this setup.

[rdkarthik]

Originally Posted by v1p3r

Also, can someone define batch, semi-sequential, and sequential, wrt injectors?

Batch - All injectors work together

Semi-sequential - Injectors work in pairs

Sequential - Each of the Injectors works independently of others.


WRT Performance there is no difference between the injection types.

WRT Emission and economy sequentials are best.

[Rehaan]

Thanks for the explaination RDK,

What about wasted spark etc?

Is that found on indian cars? Advantages / disadvantages?

cya
R

[ported_head]

Originally Posted by Rehaan

What about wasted spark etc?

Is that found on indian cars? Advantages / disadvantages?

cya
R

Wasted spark is nothing but Distributorless Ignition System (DIS). It runs two double ended coils, one coil catering to two spark plugs. So two plugs fire simultaneously. The one on the compression stroke at TDC makes use of it, the other is wasted. The paired plugs are alternate, like 1-3, 2-4, etc. The Swift and the Baleno run DIS setup. They take timing reference from the crank position sensor. No maintenance required, since controlled by ECM.

Does the Swift run CMP or CKP? If it does run a CMP, the iginition timing is referenced from the CMP then? And in the Baleno from the CKP?

[Ford Rocam]

Ford 1.3 & 1.6L Rocam & Duratec Engines also has Cam & Crank Position Sensor, as explained by ported this engines also runs wasted park one of cylinder will be firing in compression stroke where as same time it is also firing in exhaust stroke in other cylinder.

[mclaren1885]

Originally Posted by ported_head

Does the Swift run CMP or CKP? If it does run a CMP, the iginition timing is referenced from the CMP then? And in the Baleno from the CKP?

I guess the baleno and the swift run off both the cam position sensor and the crank position sensor .. Both have to work smoothly , i broke both of them on my car .. Car gave immense problems , apart from being expensive , parts such as these are really hard to find too ..

[ported_head]

FR, didn't the Ikon 1.6L run sequential fuel injection? They advertised SEFI a lot, didn't they? Are there any other Indian cars that run Sequential injection?

[dragger]

this is by far the best thread according to me here on t-bhp,lets not go off topic and concentrate on the electronical aspect,im personally very grateful to rdkarthik for prompt replies and sharing very valuable knowledge cheers happy revvin..!

[rdkarthik]

Originally Posted by ported_head

FR, didn't the Ikon 1.6L run sequential fuel injection? They advertised SEFI a lot, didn't they? Are there any other Indian cars that run Sequential injection?

Almost all cars availalable today run SEFI.

Dual distributor-less ignition system (DDIS)-
Adv-
1) Most stock coils are good enough more than 10000RPM, as coil charge times can have almost 360 deg of crank time... Compare them with distributor setup, where coil charge times are lesser than 180deg of crank rev.
2) No mechanical movement required to distribute spark, so no wear and tear, no adjustments necessary
3) Reference for engine position can be as accurate as a signal every 10 deg of crank angle or more, which means better timing accuracy.. Distributor types (without CKP) have a reference signal evey 180 deg, so timing can be off by a few degrees under dynamics conditions.

Dis adv-
1)Costs
2)Endurance. Many coils cannot take a constant switched-on state for more than a couple of 10s of seconds. They breakdown/melt soon after. Nothing to worry about as the ECU never lets that happen... Conventional bottle coils in distributors setups can take much more than distributirless coils


Swifts,balenos,wagonRs, accents,santros,getzs,astras,corsas,etc run off both the sensors. However, the min requirement for a Dual Distributor-less setup is just a Crankshaft Position Sensor (with the right crank sensor wheel patten). Reference for timing on systems with CKP and CMP is almost all the time CKP (under normal running conditions)

@ported head - Slight correction there. The plug pairing is 1-4, 2-3 on an engine with a firing order 1-3-4-2. When its close to TDC in one end of the pair, the other has to be in exhaust stroke.

@dragger- Glad you find them informative,mate..

@mclaren - how did you manage to do that dude? yeah, spares availability is something maruti really has to work on..

[mclaren1885]

Originally Posted by rdkarthik

@mclaren - how did you manage to do that dude? yeah, spares availability is something maruti really has to work on..

Its a long story karthik , infact even the crank pulley was broken .. I am glad that ranjit helped me source it hours before we left to bombay for the drag ..

[v1p3r]

Can someone explain how batch and semi-sequential injectors work? If all injectors run the pulse together (batch) aren't you wasting a helluva lot of fuel? Or am I getting it wrong?

[rdkarthik]

Originally Posted by v1p3r

Can someone explain how batch and semi-sequential injectors work? If all injectors run the pulse together (batch) aren't you wasting a helluva lot of fuel? Or am I getting it wrong?

For batch and semi sequential, the total fuel required is split in half and injected twice per 720 deg of crank rotation... In sequential full fuel requirement is injected once every 720 deg.
Net total fuel injected irrepsective of type is tha same.

[v1p3r]

Originally Posted by rdkarthik

For batch and semi sequential, the total fuel required is split in half and injected twice per 720 deg of crank rotation... In sequential full fuel requirement is injected once every 720 deg.
Net total fuel injected irrepsective of type is tha same.

You mean half is injected during intake and half during compression? Won't this mean less-than-perfect burn characteristics?

[rdkarthik]

Originally Posted by v1p3r

You mean half is injected during intake and half during compression? Won't this mean less-than-perfect burn characteristics?

No. The cylinders get the required fuel they need.. What happens before the valve opens does not matter, as long as the total fuel getting into the engine is correct. In fact injection when valve is closed helps reduce intake valve temperatures and improve fuel atomisation..