A bit more Go.

Make it go fast! Kick it up a notch. Post tips in here.
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Lstdnsr
Posts: 3
Joined: Tue Aug 22, 2023 12:38 pm
Your car is a: 1981 fiat spider

A bit more Go.

Post by Lstdnsr »

Just picked up a new 81 FI. Would like to tweek a bit more horsepower without going crazy. Seen and heard of couple emmission system deletes and was wondering if anyone had any ideas.
MIGHTY 8
Posts: 307
Joined: Sat Mar 04, 2006 9:55 pm
Your car is a: 1980 Spider
Location: North Chatham NY

Re: A bit more Go.

Post by MIGHTY 8 »

Been down this road! If "not going crazy" is truly part of the equation, I would suggest an aftermarket exhaust with the deletion of the Cat, and the second resonator.
Removing weight would be very advantageous and truly inexpensive. Bumper deletes…those two weigh about 150/200 lbs, if I recall correctly. Spare tire? Another 20 lbs or so.
Installing a lightened (aluminum) flywheel would also be pretty straightforward and produce a great result.

Have fun!
18Fiatsandcounting
Posts: 3791
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: A bit more Go.

Post by 18Fiatsandcounting »

The FI system does a very good job of keep emissions in check, so there really aren't that many emissions devices on an '81 FI car, with the exception of the catalytic converter.

Power is determined by how much air/fuel you can stuff in the cylinders, and the compression of that mixture, so about the only performance mods you can do to an FI car is high compression pistons, larger valves, performance camshafts, cylinder head modifications, etc. If you move the torque curve upwards in the rpm band, your power at high rpms will increase but at the expense of low end power. In all cases, the ECU will automatically adjust to keep the mixture correct (if working correctly).

Mighty 8's suggestions are a good place to start, and if you want to spend some coin, see the above paragraph.

-Bryan
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