1981 FIAT Spider Turbo


Note the custom louvered hood. This photo was taken inside when the engine was being rebuilt.


Newly rebuilt engine, new Electromotive Tec3r computer, and a brand new top. Mechanically perfect.
Good tires on 14" Cromodora Turbo wheels.

FIAT (and Legend Industries) used the same computer on Turbos and regular Spiders. They just 'made do' with the Bosch CPU made richer on boost with some add on Hobbs pressure switches that modified the signal from the coolant temperature switch.
The the stock Marelli distributor has no provision for boost retard. It is just wrong for the job. We removed the distributor because the Tec3r handles the ignition. We removed the air flow sensor because not only is it restrictive but it is unecessary since we have a MAP sensor to signal the computer about the incoming air.

We installed an excellent complete engine management system onto this FIAT Turbo. An Electromotive Tec3r handles mixture and ignition.

We proved that NO Turbo spider could run well with stock injectors. It ran out of steam at 4500 RPMs. The stock injectors were open all the time. 100% duty cycle. We installed larger injectors. Our new 40 pound injectors need only 80% duty cycle at top boost and 6,000 rpms

A wide band O-2 sensor guides the mixture towards optimum air/fuel ratio at each breakpoint. A breakpoint defines mixture and ignition timing at a specific rpm and throttle opening. We aim for 11:1 air/fuel ratio at max boost on down to 14.4:1 at cruise and idle. The computer corrects for those ratios based on input from the O-2 sensor
We have breakpoints set 300 rpms apart at low rpms. Above 2400 rpm we have breakpoints 400 rpms apart. Most computers will not allow breakpoints closer than 500 rpms apart. Electromotive is very flexible.



Electromotive allows various idle
air control devices. We use a GM IAC-
idle air control which is easy to source.
We have the cold idling set at 1200 rpms,
1100 a little warmer and 1000 rpm hot idle.




Electromotive ignition is the best in the business.
It has the most accurate timing definition and
longest duration spark of any aftermarket
computer made. The spark can be produced for
2 milliseconds and that is a long time for a spark.




Every (stock) Turbo that I have driven knocks or pings on boost.
Some of that due to crummy distributor and some due to poor mixture control and inadequate injectors.
A knock sensor retards the timing if needed and can help tune to the edge and be safe.
Every healthy Turbo could use the built-in 3 way rev limiter that Electromotive Tec3r features.


The intercooler uses all of the space on the right side of the
engine. The distributor, coil and airflow box are gone. Don't need 'em.
We relocated the coolant tank to the left side (see photo above).

We record the air temperature (among other things) during a run-up through the gears to learn about the intercooler.

Before we installed intercooler there was an inlet air temperature increase of 25 degrees Centigrade on a single run-up through the gears.
After our first generation ducting -- 1 degree DECREASE in air temperature through four gears.
Testing the current configuration today I was limited to only 2nd and 3rd gear run-up to redline
on boost because of too much traffic. It cooled the intake charge 6 degrees (Centigrade)!
It will probably change a full 10 degrees when I get a chance to run through 4 or 5 gears at full throttle at maximum boost.

Check out this cold air package !
The air filter is easy to service with the access panel removed. The aluminum shield completely isolates the exhaust and turbo from the inlet air. The shielding mounts to the frame at the bottom and extends to the hood from next to the radiator all the way backto the firewall yet it comes off easily for service.

All the air for the engine and the intercooler flows in from the front beside the radiator.
And the intercooler air exhausts out the hood louvers


It runs really, really well. Surprised ME! I didn't know a FIAT could run so well. It's a lot of fun to just dip into the throttle in 5th gear at 40 or 50 mph and just feel lots of torque like a big V-8. No need to downshift. It just goes. The words "Torque Monster" come to mind.


A note about aftermarket computers:
Mapping time is the most expesvie part of the job whether you are datalogging on the road or using a dynomometer.
Electromotive's software is easy to use. Electromotive even has a feature which modifies fuel maps automatically according to a datalog recording.
Electromotive Tec3r is economical when you consider the ease of mapping and all the cool features it has standard.


Now:
Newly rebuilt engine which is totally stock with minor exceptions:
the reciprocating parts are balanced finer than stock
We used a 1" wide timing belt
Apple Motor's own adjustable timing gears one each camshaft -- we advanced the intake cam 2 degrees and retarded the exhaust 1 degree.
Total Seal gapless piston rings in the engine
Cold air inlet to the intercooler & engine and louvered hood to let the heat out.
Tec3r, with idle air control and knock sensor
AND larger injectors

Future:
Apple Motor's own Delrin front suspension bushings
Apple Motor's own aluminum flywheel
Yellow Koni competition shocks if I can set them soft enough
Aluminum inlet tube between intercooler and plenum
Turbo timer OR an 'Accusump' like reservoir to oil the turbocharger after shutdown.


This car is unique and fast. It might be one of the best running Turbo Spiders in the land.
For sale -- $11,500.
I have saved the stock Turbo logo plenum, CPU, distributor, coil, air flow regulator assembly, double relay, and coolant tank. I have kept these parts to be able to put this rare care back to bone stock if that is an issue.



For more Mail to: information . OR to return to Apple Motors home page www.AppleMotors.com
Call 303-421-0571 for more info