Tuning 1.4 8v Seicento

[Ouby]

Too be honest neither can i, known many Mini owners who go for mega-sparks but achieve absolutely no improvement in performance.
As i said before -as long as you get a sufficient spark at the correct time does it really matter.
Maybe i'm wrong, who knows.

 

[fingers99]

I think the Zetec is said to require an especially good spark because it runs relatively lean. But people have been running 1.4. 16v engines (originally coil per cylinder) on stock FIAT wasted spark coils with aftermarket ECUs for a long time.

 

[Ouby]

Finally seem to have identified the emission problem - Fuel stabilization.
After sorting out various wiring issues & a badly plugged evap pipe the engine management light only flashed on acceleration/deceleration, rough ground & corners!
As i understand it the ECU leans off the injected fuel when it opens the evap solenoid, as the charcoal cannister was removed & the solenoid capped off the system will still be reducing the injected fuel but recieving no extra fuel from the evap.
Just to confirm the theory i've disconnected the solenoid- No flashing light!
(replacement cannister/pipes on their way).
I know some people have done away with the charcoal cannister but just wonder what they have done to overide the ECU leaning off the fuel?

 

[craigb244]

who ever said it leans fuel out when the evap opens?

the valve opens on over run! on over run the ecu cuts 100% of the fuel. the ecu then opens the valve and the engine sucks all the petrol fumes from the canister and the engine burns them.

the engine never actually runs or makes power from the fuel collected in the canister.... it mearly disposes of it during over run

 

[fingers99]

So, we're back to wondering why it leans out?

I can't remember what inlet mani/TB/injectors you're using. An update might remap my poor old brain.

 

[Ouby]

who ever said it leans fuel out when the evap opens?

the valve opens on over run! on over run the ecu cuts 100% of the fuel. the ecu then opens the valve and the engine sucks all the petrol fumes from the canister and the engine burns them.

the engine never actually runs or makes power from the fuel collected in the canister.... it mearly disposes of it during over run

Blast! No, you must be wrong
Googled myself silly to get that snippet of info off some obscure website, & now you tell me it's wrong
I no longer flash when i drive - but now i don't know why.

Fingers- manifold/rail/injectors all 1.1 at the moment.
1.4 stuff on it's way courtesy of Todger (everyone needs a Todger ), replacing manifold will have to wait for a while as it's not a straightforward swop.
TB is a 1.1 MPI with the restrictive step removed & the butterfly edges radiused (remember my PM last night?), certainly helps acceleration & anything over 4,000rpm but seem to have lost some mid-range, think the ECU is learning as it's getting better now (didn't do a phonic).

 

[fingers99]

It's going to need a remap at some point. The ECU will learn within about 10% (to cope with wear, manufacturing tolerances, etc.) Dunno what manifold you're putting on, but the 1.2 16v injectors (at least the early ones) are bigger than the MPI 1108 ones and are the same (tiny) Pico type. Spray pattern may be different, but can't see that mattering overmuch.

Still, it's up and running. Now you can go everywhere in 5th gear.............

 

[Ouby]

What??? I'm confused.
It's always been up & running, with lots of lovely torque compared to a 1.1
- but in it's current set-up it's just not as good as it could be.

 

[fingers99]

It's always been up & running, with lots of lovely torque compared to a 1.1
- but in it's current set-up it's just not as good as it could be.

Ah, I'd though it was'nt running until recently.

It'll run a lot better with a remap: the ignition curve and the fuelling will be a fair way out.

 

[craigb244]

It's going to need a remap at some point. The ECU will learn within about 10% (to cope with wear, manufacturing tolerances, etc.) Dunno what manifold you're putting on, but the 1.2 16v injectors (at least the early ones) are bigger than the MPI 1108 ones and are the same (tiny) Pico type. Spray pattern may be different, but can't see that mattering overmuch.

Still, it's up and running. Now you can go everywhere in 5th gear.............

wouldnt recommend fitting 16v injectors in an 8v...

I tried with my 8v engine and an amount of tuning would get it to run very well (it was OK at high rpm)

the fiat injectors squirt two streams ... one for each port... not only that they also squirt at an upwards angle. on the 8v all you will get is the fuel squirting right at the top of the port about half an inch from the injector.

 

[fingers99]

I was a bit worried about the angle -- the spread, if you like, but with the Picos, there's no apparent way of lining them up accurately so they'll spray up or down (or even sideways).

Do you think the stock 1108 MPI injectors are up to a 1.4?

 

[craigb244]

I was a bit worried about the angle -- the spread, if you like, but with the Picos, there's no apparent way of lining them up accurately so they'll spray up or down (or even sideways).

Do you think the stock 1108 MPI injectors are up to a 1.4?

you sure? I have a fuel rails and manifolds from lots of fiat engines (1.1/1.2 8v 1.2/1.4 16v) and all the 16v engines the little clips that go over the input side of the injector have a tab on them that locates into a hole in the side of the injectors and its keyed to the fuel rail.



not sure about them been big enough. I know they wont be anywhere near maxed out (no manufacture would push injector limits) I have mentioned to Ouby in a pm... I recon most fuel map issues could be solved with a decent adjustable rising rate fuel regulator.

 

[fingers99]

I'll take a peek next time I see one. The only one I have is so disassembled (and missing one injector) that it would take me ages to find all the bits again!

 

[Ouby]

I recon most fuel map issues could be solved with a decent adjustable rising rate fuel regulator.

Unfortunately the 1.4 fuel rail/injectors didn't arrive today so i won't get to play with them this w/end
Charcoal cannister did arrive so i will get back to you on whether it stops me from flashing

 

[Todger182]

Sorry bud, been rushed all week with work and other peoples cars :bang:. I'm finally going to have a few moments to myself this weekend so hopefully I can post it out first thing in the morning.

Thanks

X

 

[Ouby]

Boo!

In order to move the 'project' forward can anyone suggest a Fiat/Lancia (not Rover) TB that will be less restrictive than what i've got without ruining the torque.
Did read an article by Kritip that the 1.2 1.6v has a 42mm butterfly but found references by others to it being 38mm??? Can anyone clarify this, or what size a 1.4 8v would have had.

 

[Eklipze3k]

My missus actually has a 1.4 8v, so I could go measure it for you

Not right now 'cos it's cold outside, but tomorrow if no-one knows off hand

 

[Ouby]

My missus actually has a 1.4 8v, so I could go measure it for you

Not right now 'cos it's cold outside, but tomorrow if no-one knows off hand

Did you know you're my hero
Did post request on GP & Punto forums for info but....

IF you get the chance (without the missus ripping off certain parts for pulling her car to pieces)-
What size is the exhaust pipe?
What's the fuel pipe bore?

 

[fingers99]

Fuel pipe bore won't matter.

 

[craigb244]

don't expect anything much larger then the moisture 1.2 8v throttle body. the heads are identical and restriction is the head