Seicento Monster Cento/ECU Master Thread

[Honeymonster]

I see so the injection divider is set to fire the injectors once every 180 degrees?

You simply run out of time for it to inject the fuel before it starts it's next calculation?

This is one thing I have an option for on DET. I can select an injection divider between 1 and 4. It recomends to select 2 or 4 revolutions for batch, I guess giving me more scope/time to add fuel.

However I would think set at every revolution it would add the most fuel, hmmm confusing.

EDIT:

A little bit of research later reveals we have more fueling time because we don't have to take into account as much injector dead time (the time it takes for the injector to open) if we make bigger injections over a period of more revolutions. You wouldn't think it makes a massive difference but apparantly at high RPM's it actually does.

 

[woj]

My ECU fires the outputs once every crank rotation. I am not sure if the actual fuel calculation is crank-synchronous, but programming the outputs certainly is.

Only now I checked this calculator you quoted, it is actually quite accurate, it says I should be having 260ccm injectors for my power, which is only 10ccm away from what I have

 

[Honeymonster]

Hmmmmm, means mine are well under but we'll see.

Meh, I prefer this one shamelessly stolen from the Megasquirt link you posted:



Why? because it says I'm only about 10% under after adding the turbo correction (150hp), however it states 85% duty cycle.

I don't trust any of them to be honest, "one test is worth a thousand expert opinions".

 

[woj]

Actaully, if this table is for 3 bar at the rail, which I would assume it is, then it is also practically spot on for what I have In all honesty and according to quick in-head calulations, I think your injectors will be good for ca. 130 HP when run on 3 bar of pressure. It also depends on how rich you want your boost fuel to be, mine is setup to be at most 11.5 on full boost, sometimes lower. What I mean is I waste the potential power by using the fuel to drop the EGT for safety.

Well, the game seems to be slowly starting

 

[Honeymonster]

I will be tuning to RBT (Rich Best Torque) so fueling will be exactly what it needs to be. No Super (98) though it's getting to damn expensive and prices are only going to get worse.

I wouldn't be going for a max power tune if I didn't have the choice between 2 settings for the road. Also now we have plenty of time on a load bearing rolling road it would be rude not to try and find out what it's capable of.

I need to have a closer look at my compression ratio this week though as it seems no exact figure has ever been disclosed. I know the block has been skimmed along with the head, I need to check it hasn't been made too high, even with the 16v pistons.

Gazz's thread on the engine is a bit vague regarding final compression:

https://www.fiatforum.com/cinquecento-seicento/188593-turbo-banana-seicento-project-2-a.html

It will be a lot easier to check it now before it's squeezed into the engine bay that's for sure.

This weekend will be about doing everything prior to the engine swap, next weekend it's going in the hole. :slayer:

 

[blu73]

from my research about using 16v pistons in a 1242 8v block (thats not been skimmed at all) it would make the compression ratio 7.8:1 which is quite a bit lower than my VA turbo which is 8.5:1

I very much doubt that a skim even to the max line on the head would make it too high again and as i understand it you can't skim a block much at all either (waits to be told he's wrong).

That said it always nice to know what it actually is.

 

[Honeymonster]

Well you'd hope so Blu, but I'd rather find out now before I put it in.

It doesn't say how much he took off, just that the pistons protrude 0.3-0.4mm and the head has been skimmed (probably to the marker) which could be quite a lot?

Supposedly a 1.5mm decomp takes a 75 to 8.5:1 so it could easily be 8.2ish+ prior to the skimmed head. I don't know what difference a skimmed head can make, doesn't seem to be any definitive figures on the forum.

 

[blu73]

no i looked for ages, doesn't seem to be anything concrete on here regarding it.

 

[Honeymonster]

Indeed the only thing I could find was this started by Arc in 2007, and even that's for a 1.1

https://www.fiatforum.com/cinquecento-seicento/111837-compression-if-head-taken-max-markers.html

No bother, I'll get the oil out and double check in the next few days.

 

[woj]

Well, for the head skim and calulating CR I assumed the following. Each 1mm of head skim is worth the same as 0.6 skim of the block. This rough relation comes from the area differences between the full cylinder area, and the head comb. chamber area. But the best thing that you can do is to measure the combustion chamber by pouring cerosine (spell?) into the fully lifted cylinder and the head comb. chamber and using a piece of plexi. Sure you can find some manuals on google on how to do it.

 

[Honeymonster]

Ah you mean kerosene, however your spelling (and English) is generally better than mine.

Yeah I'm planning to do the same thing only with light oil. I'm sure it will be fine but I doubt I'll be able to use the steel gasket, which I would have rather used after our conversation the other day.

It's no trouble, it's the best option anyway.

 

[fingers99]

You might look at a solid copper gasket from Ferriday. With care, they're re-useable too. My best guess, the CR will be fine.

 

[Honeymonster]

You might look at a solid copper gasket from Ferriday. With care, they're re-useable too. My best guess, the CR will be fine.

Ah, Mr. Fingers where have you been? It's been most quiet around here without you.

Yes I beleive it will be fine too, infact after sleeping on it I might try it as is rather than waste a new head gasket and set of bolts. Once I have killed the gasket (however long that is) I will take a measurement. Also it's a bit of a pain to measure cr with protruding pistons. I have an incling it will be just right or slightly too low. If it's too high it would be a real pain to do anything about it anyway. I've ordered a set of Payen bolts and a gasket anyway just incase...

 

[Honeymonster]

Stuck the sump on with some high quality RTV today





Also the convoluted T pieces turned up for tidying the wiring. I even managed to get the large sizes (like the ECU loom) which Fiat had just tapped, so it will actually be better than factory.



Also here's a useful link if you want some spare pins for your DET 3

http://www.ebay.co.uk/itm/310407125520?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

And a tool to remove the pins

http://www.ebay.co.uk/itm/170856629369?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

I got some spares so I can shorten and tidy things as neccesary to put the ECU behind the carpet next to the PS ECU.

I also got some adhesive lined heatshrink to make some of my connections completely permanent. This stuff is bullet proof and adds awesome strengh to soldered conections and components (like the Zener) which can otherwise be quite brittle.

 

[Honeymonster]

Well the weekend hasn't been as productive as I would of liked but I've got a fair bit done.
I had a strange slight hesitation which I traced to the Zener. After doing an on car test similar to Woj's experiment I found that due to a Zeners leakage before its breakdown voltage (all Zeners leak) it was cutting the voltage a bit lower than required. After trying a few more diode sizes I found a 5.1 Zener regulated to exactly 4.75, perfect.

I also gave the MAP sensor a good 3+ bar of pressure while testing, and this wasn't enough to break it so I'm not expecting any issues while potentially running a bar+ of boost.



I fitted the fuel pump, finished wiring all the gauges and running their sensor cables into the engine compartment. I haven't fitted all the convoluted cable tidy and shortened all the cables yet as I want to get the motor in and running first incase I need to make any changes.
I offered the intercooler up to check for fitment, no issues here however there is a manufacturing defect with the intercooler so I'll have to return it for a replacement. :bang:



I hope to finish assembling the engine this coming week and at have it fitted along with the box by the end of next weekend.

Then with a bit of luck running half decent and ready for the RR the following weekend. :slayer:

 

[centoproject]

good progress rail is nearly done as well

 

[woj]

Looking good mate , one thing for consideration that perhaps you missed now looking at your pics - the charcoal canister

 

[Honeymonster]

Looking good mate , one thing for consideration that perhaps you missed now looking at your pics - the charcoal canister

Ah you mean that silly thing I will be blocking off and throwing in the closest skip?

Yes I still need to remove it, but I will do that when the bumper comes off next weekend.

 

[woj]

You can also simply put a suitable one-way valve on the connection. If you throw it out, either you have to leave the electro valve itself, or replace it with a suitable resitor. All this to make the ECU happy

 

[Honeymonster]

Resistors and soldeing iron ready, I'll be doing this to the injector output too. Do you know if the ECU is clever enough to determin load/resistance or if it just checks for an open circuit?