My 88 GT fastback has been having overheating problems, especially on long highway drives. So far I have avoided full overheating by turning on the AC/radiator fan.
The air deflector/wing at the bottom of the radiator was missing but I didn't think it made that much of a difference. I constructed a new wing from Plexiglas and now the overheating issue is all gone So, check that you have a wing there if you have overheating problems.
BTW, I believe that the Fiero Store sells replacement air dams. One of my project cars had a 12" plus tear in it and I elected to replace it instead of trying to repair it. The price was not too bad either.
Even here in Florida with relatively smooth roads, an air dam can take a beating. I had a fiberglass air dam on my Fiero... all it took was the right (or maybe the correct word is wrong) railroad crossing, and that air dam was in pieces. I made a flexible plastic air dam to replace the broken one, because I didn't want to deal with that again.
Yes I know that it might crack and this was only meant as a proof of concept. Only the "core" is Plexiglas, and I have wrapped it with multiple layers of duct tape. Probably make a new one in thick rubber or similar if this one breaks.
[This message has been edited by blyfot (edited 04-30-2017).]
In addition to the air dam, you want to make sure the sides and top of the radiator are sealed as well.
Above 35 mph, the car moving at speed should force enough air through the radiator to keep the car cool with the radiator fan turned "off". If it doesn't there is something wrong.
I recently installed a "Munson" bumper from Fiero Fiberglass that hangs about 2" lower than stock. My car has the air dam and my car didn`t overheat but it wouldn`t cool down very fast after going from a stop to highway speeds. It is a 3800SC so maybe a little different from stock. I got a piece of vinyl base like used for office baseboard and attached it to the stock air dam hanging about 2" lower than the stock one. Problem solved, the temp will now drop at least 5 degrees pretty quickly and if I hit anything it is flexible enough to bend back. I got a 4 ft piece at Lowe`s.
Corvettes air dam is made of stiff rubber, but simple to change them since they know their going to get banged up. I know Camaros and Firebirds are also critical to needing it or they overheat. Id make one out of hard rubber rather than just replacing it.
Been driving for a year without this air dam (bumperpad body style if it makes a difference) and I put it back in a few days ago after I finally repaired it.
My conclusions are:
1. Highway driving 50-85mph no difference at all 2. When driving through town without the air dam the temp will rise quicker especially when slowing down. When keeping speeds about 20-40mph in town there's no difference in temps - only that moment when you slow down and stay a little while at some traffic lights. 3. Looks a lot better though with the air dam installed. Without it the bumperpad looked kinda "naked".
All this according to the stock temp gauge of course, so yeah... not too accurate but there you go.
Overheating can ruin an engine real quick -BTDT-; to avert such again, I put toggle switches wired to the radiator fan relays of my 2 GTs and thus can avert overheating by switching the fans way before things get hot. Additionally both of my GTs also have extractor hoods. Such is not overkill; whereas they have very modified 2.8 engines and require 93+. Toggle switch 2-3 $ verse engine rebuild, install one!
3. Looks a lot better though with the air dam installed. Without it the bumperpad looked kinda "naked".
Not sure that we are talking about the same air dam here? Mine is not visible, unless you are laying on the ground and looking under the car. It's right below the radiator. Perhaps it's visible with the nose that your car has?
Yeah I think it's the same thing we're talking about. I've got the stock bumperpad nose and it's much shorter than the aero ones. You can see it clearly when approaching the car from the front up until you get real close.
Like in this pic (it's the whole black thing under the car)
Or in this pic (it's starting to fall off already)
Nice angle here though low res pic
[This message has been edited by cebix (edited 05-04-2017).]
So, check that you have a wing there if you have overheating problems.
