Fiat 500 Abarth swap into vintage Fiat 500 questions.

I read TonyK's thread about his 500 Abarth swap, and another one has a few posts deleted.
What I've learned from those is that the everything is connected to everything, electronically, and it is all made to be tamper proof.

Seems to me, this is much more complicated than I need for a non emissions racecar that will be used on the track only.

So here are my questions...

Would it be possible to override the solenoid that contols the valve timing?
I think I'd only need the power mode ( plus possibly the low RPM torque mode).
I plan to use a Hewland racing transmission, so I will have unlimited ratios to choose from to keep it in its powerband.
As long as it will start, and idle, somewhat...

I'd probably get rid of the fuel injection system, and use a boost referenced mechanical Hillborn instead.
Or make a new intake to adapt a carb and pressure box off a '80s Maserati Biturbo ( I've done this on my Pinto powered sandrail, and it works very well )
Or pressurized IDF Webers, thanks to the off road VW guys everything is available for that as well.

Which leaves the ignition.
But it seems to me a simple & basic stand alone system would take care of that.

What I haven't been able to find out yet is what the engine weight is.
( stripped of everything it doesn't need, like A/C pump, power steering, and whatever else might be there. I'd like to keep the alternator, but I might put in a smaller one if it seems too heavy )

Engine weight is pretty crucial for me, my car is light and the engine hangs out behind the rear axle.
It would be really easy to mess up the weight distribution.

And the actual size of the engine is important too, I have lots of room to the sides and the rear, but not so much in height.


What are your thoughts on all this?

Is the engine itself sturdy and reliable enough to make it worth my while?
At the stock 165Hp it probably isn't stressed that high...

Questions...Answers

This may get a bit long winded but I will try and answer what I know and give you some direction.

My Abarth X1/9 weighs in at 2195 pounds with full fuel and A/C. So I think the engine is a bit lighter than the stock 1987 X with A/C possibly someone on the board had the weight off of the top of their head.

The engine is a bit wider as it is a cross flow head compared to the stock 138 engine. This engine does not require any cutting of the side rails in the X1/9 engine bay. it is about the same height as the 138 engine.

Power steering on the Fiat 500 Abarth is an electric servo motor and does not have a hydraulic pump or system. The alternator is 140 amp I think.

Now the complicated stuff. The exhaust valves run on a full race fixed camshaft lobes. The intake is another issue. It is not like the Honda engines that use 3 grinds on a camshaft and a follower that changes between grinds. The intake lobe is an eccentric lobe that is connected to a rocker arm that moves a plunger to produce 1500 PSI hydraulic pressure to operate each intake valve lifter. Connected to the oil way is a very fast operating bleed valve solenoid that the computer opens and closes to allow the valve to follow a camshaft profile that is computer generated. I will guess here that the bleed valves are normally open as I have seen when cranking, intervals of no compression. The easiest way of checking this would be to pull the electrical connectors from the bleed solenoids and crank the engine. One of two things will happen as you crank, the engine will have no compression as the intake valve will not open or the opposite where the valves will stay open and the piston will strike the open valve. ( If you ask me to try this I am going to pass on that experiment.)

So if you want to run this engine without the stock ecu, you must find a way of opening the valves at the correct time and closing them as well. It may be easier to have a custom camshaft made up to drive solid lifters, just guessing here. You will also have to synchronize this with timing and fuel injection. Plainly this is getting complicated.

The blow off valve on this engine is also ECU controlled so you will have to figure out another way of doing this as well. Then there is a knock sensor on the block of the engine to contend with. As for boost pressures I am seeing at times of about 24 PSI peak and holding at 21 psi. Limiter cuts the engine at about 6200 RPM.

What you are talking about is a complete engine management system and in high boost the timing is retarded to about 0 degrees.

By keeping the stock ECU you will be able to use after market tuners and tablets providing that the ECU you are using is 2012 to mid 2014. After that Magnetti Marrelli encrypted the ECU's and the tunners have not been able to crack the ECU code to retune them. Using the stock ECU requires all of the peripherals the ECU is looking for to run. Going this route will require a lot of stock OEM parts from a car, of which many will need to be mated from the same car. Again costs will go up and the time it takes to harvest the parts from the car.

Hopefully I have been able to give you a bit of insight into this matter.


TonyK.

Grimsby Ontario Canada.

Thank you for all the info Tony.

I really appreciate it.

So it sounds like using the stock ( early ) ECU is the only real option.

Unless...
Is there some Euro version ( Punto maybe?) head with regular cam timing that would fit the engine?

I wouldn't mind using the ECU, as long as it is absolutely bomb proof.
If it decides to go into limp home mode on the track that would mess up the heat, and if I cant fix it, the whole race day.
(I like Webers because I grew up with them and I can work on them at the track...)

My car with the 1000cc Abarth pushrod engine in it weighs 1040Lb, so any component that has to go on a ride is an issue...
But, as long as I can keep the weight distribution close to what it is ( almost a perfect 40%F/60%R ) the stock 165Hp would make it fly...

I've got some things to think about...

Thanks again.

Out of curiosity...

...reading this thread makes me want to turn away quickly and look for a different (simpler) option.
Why do you want to use this engine? Because of the Fiat 500 family relationship?

That it is a Fiat engine is a bonus, but not the main reason.

I'm looking for something that is about the right size, weight, and HP for my car.

And looking at Ebay, etc, the low mileage 500 Abarth & Dodge Dart engines are relatively cheap.

I also want the engine to work with the Hewland gearbox I have, so that leaves most motorcycle engines out.


But I am looking into Moto Guzzi and BMW bike engines...

metalshapes said:

That it is a Fiat engine is a bonus, but not the main reason.

I'm looking for something that is about the right size, weight, and HP for my car.

And looking at Ebay, etc, the low mileage 500 Abarth & Dodge Dart engines are relatively cheap.

I also want the engine to work with the Hewland gearbox I have, so that leaves most motorcycle engines out.


But I am looking into Moto Guzzi and BMW bike engines...

Click to expand...

IF you are at all comfortable with a COMPLETE Japanese drivetrain, there is always the k series swap. Here is a chap who swapped one into his classic mini:

http://www.theminiforum.co.uk/forums/index.php?showtopic=102232

Went RWD (and engine) too!

That is really cool.

But slightly different from what I want to do...

Awesome car, though...