Tuning 1.2 8v cinq info ?

[fingers99]

There is no reason at all you can't just buy a complete 16v bottom end and use the whole thing is there??

I think there's some issue with the head gasket not being quite right.

But if I had a 16v bottom end, I'd probably have a 16v top end, in which case Craig's solution (although it scares the metalurgist in me ****less) would be netter still.

 

[blu73]

interesting, will have to take a closer look at that block i got then

 

[Honeymonster]

Anyone know if the 16v block has the skirt/piston oilers?

 

[fingers99]

I'd guess so -- AFAIK, even the later P60s do.

 

[Honeymonster]

Ah yes it's all here:

https://www.fiatforum.com/cinquecento-seicento/262227-engine-turboing-would-still-good.html

Must remember to use the search function.

It also sais the 16v block will fit, is reinforced and has a better crankshaft (Brooky?).

But I guess if there is a problem with the headgasket like you say Fingers, Blu will have to make some alterations. Still seems it would be worth the effort if it can be done.

Not seen the 16v stripped in the flesh so I can't vouch for this information. Certainly interesting to know of these potential improvements though.

Maybe you can have a look and confirm the differences Blu.

 

[fingers99]

I think Peter at GSR (formerly Oldschool here -- now at Performance FIAT site) has done some stuff on the 16v/8v fit. From memory, there's nothing that can't be done/undone. The bottom end of the alloy sumped cars is stiffer (but maybe not really stiff enough -- 'tis said that the T Jet has a better crank still) by virtue of a web.

I'd go the 16v top end, every day -- if you're going MPI, there's no point at all in doing otherwise, but, a copper headgasket could solve 8v to 16v mismatches (IIRC, only with the oil and water galleries, and not all of them).

 

[djindiano]

For a P60, I'd go for 1.2 16v pistons and rods over either machining or a decompression plate. Otherwise, with blu.

if i go for the the 1.2 16v pistons will that lower the CR ? and if i use them would i be using the crank to or just the pistons ????? and if the 16v pistons lower the CR i will use them

and iv herd read so much about the second injecter but i still dont get it and i dont get y it is needed because im using a ford rs fuel pump and a fuel pressure reg why would i need it ???

 

[fingers99]

To reduce the CR on a 1.2 8v, you need to use the 1.2 16v pistons and rods. The rods have the same big end, but the small end (and thus the gudgeon pin) are a different size.

Go MPI and, while you'll need larger capacity injectors, you can forget about the nasty, nasty, second injector folk use on the SPI cars. It'll give you better, more controlled, fuelling, and mean that you can run a proper, grown up, ECU in stead of an overpriced, compromised, bodge.

Within reasonable limits, the fuel pressure doesn't do an aweful lot with regard to the fuel delivered at the cylinder. That is governed by the capacity of the injectors. It really doesn't matter a stuff which fuel pump you use (and they're not expensive, so I'd personally not use a second hand one out of an old Ford), provided it can deliver enough fuel at the correct pressure. More important is that the pump cartridge fits in the carrier in the FIAT, which fits in the tank, etc. These folk are suppliers of known good kit and sensible advice. Their prices are pretty keen, too.

Now, you've revealed what you don't know. You need to decide whether to go for an SPI set up (crap, in my humble opinion) or an MPI one (welcome to the first decade of the 21st century!) and to do a fair bit more reading. The books at the top of the page here are a good place to start.

 

[djindiano]

To reduce the CR on a 1.2 8v, you need to use the 1.2 16v pistons and rods. The rods have the same big end, but the small end (and thus the gudgeon pin) are a different size.

Go MPI and, while you'll need larger capacity injectors, you can forget about the nasty, nasty, second injector folk use on the SPI cars. It'll give you better, more controlled, fuelling, and mean that you can run a proper, grown up, ECU in stead of an overpriced, compromised, bodge.

Within reasonable limits, the fuel pressure doesn't do an aweful lot with regard to the fuel delivered at the cylinder. That is governed by the capacity of the injectors. It really doesn't matter a stuff which fuel pump you use (and they're not expensive, so I'd personally not use a second hand one out of an old Ford), provided it can deliver enough fuel at the correct pressure. More important is that the pump cartridge fits in the carrier in the FIAT, which fits in the tank, etc. These folk are suppliers of known good kit and sensible advice. Their prices are pretty keen, too.

Now, you've revealed what you don't know. You need to decide whether to go for an SPI set up (crap, in my humble opinion) or an MPI one (welcome to the first decade of the 21st century!) and to do a fair bit more reading. The books at the top of the page here are a good place to start.

i already have my engine its spi

 

[fingers99]

Just get an MPI head, Punto 75 for choice, and get the inlet manifold with it. It'll bolt straight on.

SPI with the kind of power output you're after is just asking for trouble.

 

[djindiano]

Just get an MPI head, Punto 75 for choice, and get the inlet manifold with it. It'll bolt straight on.

SPI with the kind of power output you're after is just asking for trouble.

if i got the mpi i would have to change the loom wouldnt i ?

 

[fingers99]

A fair bit of it. But if you run a proper ECU (and you'll really struggle to get that kind of power with any sort of reliability without one) you'll have to do some cutting and chopping about of the loom anyway.

It'll give you backache and a degree of intimacy with a soldering iron and hair dryer (for the heat shrink) you'll never have wanted, but it's not brain surgery or rocket science.

The Canems manual (just for reference, it's one of a fair few that'll do the job properly) is here.

 

[djindiano]

that thing looks like a nightmare to work :

 

[fingers99]

Nah. The wiring isn't overly complex and all the detailed setting up is done by a nice man with a rolling road. Essentially, you just find the sensors and attach the right wires to them.

Honeymonster recons that the wiring up of his piggy back system (which should be able to deal with 4 injectors, no problem) was easier than a stand-alone.

 

[djindiano]

may i ask what is the second injecter for agen ??

and where can i get the torque settings for the crank and the pistons for the 1.2 8v engine ??? for when im putting them into the 8v engine from the 16v engine ?

and i take it it would be a good idea to get all new bearing as well ???

 

[fingers99]

The 2nd injector?

It's a bodge! The idea is that the first (original) injector supplies enough fuel for the engine in off boost conditions. When it senses boost, the MF2 brings the second injector into play.

If you think about it, a turbocharger doesn't supply air/fuel, but only air. If there's no way to supply extra fuel (or if the calibration is off) then the mixture goes lean and things start melting.

Unfortunately, SPI set ups are pretty crap at fuel distrubution at the best of times and, in addition, the spark advance/retard needs of the engine vary pretty extensively depending on engine speed, throttle opening and boost. The MF2 can't do this, and although VAD allegedly supplied a chip with different ignition curves, the SPI ECU can't tell boost from bananas, unless Woj has been at it. Stuff melts. Regularly.

The Punto manual -- even the Haynes one -- will give both. Ideally, check tolerances with plastiguage, and surface condition with a lupe or a magnifying glass. If the shell bearings are OK, it's pointless replacing them (and, AFAIK, no-one makes performance shells for the FIRE engines). Otherwise (or if there's ovality on the crank) see your engine re-manufacturer.

You might want to use better quality bolts for the big ends.

 

[djindiano]

so would a upgraded fuel pump and pressure reg not help that problem ???

and thank you

 

[fingers99]

They'd be necessary, but only part of the solution. To rephrase what I said earlier, the injector supplies the fuel to the engine. Providing the fuel is supplied to the injector at the right pressure (regulator and fuel pump) and in the right quantity (fuel pump) then a correctly sized injector will be capable of supplying the needs of the engine. But the injector is just a dumb tap turned on and off by electricity, so it needs the ECU to tell it what to do.

You've not been reading your homework, have you?

 

[djindiano]

They'd be necessary, but only part of the solution. To rephrase what I said earlier, the injector supplies the fuel to the engine. Providing the fuel is supplied to the injector at the right pressure (regulator and fuel pump) and in the right quantity (fuel pump) then a correctly sized injector will be capable of supplying the needs of the engine. But the injector is just a dumb tap turned on and off by electricity, so it needs the ECU to tell it what to do.

You've not been reading your homework, have you?

im just trying to understand the second injecter thing lol

 

[fingers99]

The crudity of it is that the first injector just can't supply enough fuel when the engine is on boost, and the whole thing is too damn dumb to control one injecrtor.

In practice, those set ups use 2 fuel regulators, the original (for the original injector) and a second, aftermarket one (for the boost set up).