I'll try and address all the questions in this thread in one post, so this may be a bit long.
The Euro 500 Abarth does NOT share the same engine as the 124. It uses the "T-jet" 1.4, NOT the Multiair 1.4. The US 500 Abarth and and all other US Fiats use the Multiair 1.4.
So the question is will the T-Jet bottom end parts fit the Multiair engine? At first glance, it looks like they will as I don't see much difference in the bottom ends. However I have not personally seen the inside of a T-Jet engine and there could be small differences like rod length, or wrist pin offset that would prevent interchanging these parts. You are going to have to ask the vendor about this. They should know as they have the 1.4 Multiair in Europe in the Alfa Mito and some versions of the Giulietta.
How much power will the stock bottom end take? A lot depends on avoiding knock. To keep this simple I am going to reference wheel horsepower since that's the standard mentioned at the start of this thread.
I know of one engine in Las Vegas that was destroyed with only about 185whp. It was a worst case scenario, but it happened. In the particular case it had about the worst possible combination of poorly made mods to get that power, combined with record high temps that day, some other factors and bang.
On the other hand I know of dozens, perhaps a couple hundred of these engines with 220-230whp that have been running for a few years with no issues.
We get about 270whp (about 300 flywheel hp) from this engine with a stock bottom end. However there are a lot of mods needed to make that happen. The exact combination of mods needed for this is listed on our website. Unlike some other vendors, we are not at all secretive about how we do this, so for those who are curious, it may be worth poking around our site.
Could we get more power from our current combo? Yes, and we have, but not too much more. We can get it up around 290, but we haven't made 300whp and certainly no where near the 350whp that Ant mentioned. You could probably get it just up over 300whp with our combo, plus a special tune and an improved exhaust manifold.
Please understand that getting to 350whp with currently available parts will be very difficult. The car's boost sensors are only 3bar. You would probably need to boost above the levels those sensors could see, so you would need to replace them with 3.5 bar or higher sensors. That means all the manifold pressure charts in the ECU would have to be re-indexed, and that's a big job. You would absolutely need a different exhaust manifold, and although I love our 1752 turbo upgrade, I would go with something bigger if my goal was up near 350whp.
To get to 350whp I would probably want to add pistons and rods. We haven't come out with those. I think we eventually will, but right now isn't the time for us to do that.
My point here is really that with this engine, there is a very large gap between 300whp and 350whp. The higher number requires higher rated pressure sensors and an ECU map that's set up for them (which as far as I know doesn't exist as of this writing). It will also require a custom exhaust manifold a non standard turbo upgrade and probably a matching downpipe, plus I would really suggest pistons and rods. So although the amount of work and money needed to get up to 300whp is massive, 350whp is far greater.
RHB's point about getting a Porsche is valid. I think he should have worded it differently, but hey, he is a busy guy. Now I don't know what cars cost in Australia, and I don't really like Porsches. I can say that in the US building a 350whp 124 with the matching suspension and brake upgrades will likely cost over 20k (no, I didn't just add that stuff up, that's a very rough guess). Add that to the price of a 124 Abarth and it's not that far off the cost of an Alfa 4C which is a far more capable performance car. It's the same weight and can be brought to 300whp easily and even 360-400hp isn't unrealistic.
I also want to point out that 270whp in a 2500 pound car is a lot. Even the 300K Factory rally 124 "only" has about that amount.
Greg
