Fiero Engine bay vs Heat. (Page 2/3)
theogre SEP 17, 12:39 PM
Can be a lot of things.... "Big" radiator (3 or more "cores" but rad close to same size), Fan(s) on all the time, and more are often band-aid fixes and hide the real problem.

While 88 have suspension changes, the ride height etc should by identical to all other years.
So Having heat problems for OE and many engine swaps is often problems w/ coolant system and owners can't/won't fix them.

A "minor" bending of main coolant pipe(s) you may see can be a major problem to the cooling system and engine runs hot or over heats. People often have to remove both brackets under the rocker panels to look for damage but few actually does this.
Battery up front changes tire wall to fit it... Changing the wall etc to do this may change air flow enough to cool the rad.
Lower cars can screw up air flow too making any radiator to fail doing it's job.
Missing/damage panel(s) in front of radiator can do same thing for cars w/ normal ride height.
Just having crap blocking the AC condenser and/or Rad can cause big problems.
Even owner believing the myth engine runs hot for whatever reason.
Can be 2 or more of these examples and more at same time.
olejoedad SEP 17, 12:56 PM
The 88 models sit one inch higher in front than the pre-88's.
RCR SEP 17, 08:15 PM
Cool litte project, Ogre.

Bob
Formula Owner SEP 18, 10:31 AM
I have a question. Say, after a hard drive on some nice, curvy roads... you pull over for a rest stop. Is it a good idea to pop the deck lid to let the heat out?
Cajun SEP 18, 11:31 AM
I have two temperature sensors in my engine bay. I can pretty much validate what the Theorge has posted regarding engine bay temperatures.

I have a Digital A.C. system in my 86 GT. The A.C. head unit reads outside temperature. While I was making the installation I added sensors in the passenger compartment and engine area that are switchable.

[This message has been edited by Cajun (edited 09-18-2018).]

theogre MAY 20, 12:03 PM
Is close to summer and I'll likely try same test on a hot day so I'm "bumping" this.
Likely will try more temp sensors. A have different types already that can read engine and even the cat directly. (Typically Engine and Cat will spike then drop after shutdown. Engine has no coolant flow and cat has little/no air flow to cool the outside case after shutdown. Cat case temp can climb in slow/stop traffic too for same reason.)
Will try to connect old MAP to read "vacuum" likely near the vents to see if has air suck or pushed thru vents.
Air flow is more complicated because air is moving behind window but air is move under the bay and some is pushed up too so MAP reading may never mean much. I've seen other tools like could work but way too expensive to buy even used for 1 time use.

ETA--> Note above data is w/ "new style" vents w/ stamped louver metal sheet under them. Old style vents w/ hex screen allow more air flow but also allow more UV for Sun light to attack everything under them.


quote
Originally posted by Formula Owner:
I have a question. Say, after a hard drive on some nice, curvy roads... you pull over for a rest stop. Is it a good idea to pop the deck lid to let the heat out?

Sorry I missed your post...
Is often not needed but won't hurt either for most cars.
Fiero is an "odd ball" with vents for engine bay and moves a lot of air even w/ the car stopped. IOW does same but less air flow as opening the "hood" as shown above... Near 200°F running drops fast to 150° and keep dropping when parked.
Most other vehicles have little to no convection when their stopped because of the hood designs not allowing air to move.

[This message has been edited by theogre (edited 05-20-2019).]

edfiero MAY 24, 10:13 AM
For what its worth, on my SD4 engine I have engine air intake connected to a K&N Cone style air filter located inside the engine bay near the area of the stock air intake/scoop.
The scoop is not connected to anything but dumps its air very near the filter. However filter is also near the exhaust piping. In other words there is potential for both cool or hot air to be sucked into the intake.
I have a intake air temp sensor feeding the updated ECU. The air temp typically starts out around 10 degrees warmer than than ambient air and increases to around 30-35 degrees above air temp as the engine gets up to full temperature. So just sharing another data point that it does not get overly hot in the engine bay.
2.5 MAY 24, 10:30 AM

quote
Originally posted by Formula Owner:

I have a question. Say, after a hard drive on some nice, curvy roads... you pull over for a rest stop. Is it a good idea to pop the deck lid to let the heat out?



The heat will get out the two big vents fast enough IMO.
One thing I did on one Fiero was remove the lower grill that is in the vent, air flows faster now.
But yeah don't park under trees/etc then (which I don't) because more debris can fall in, the good thing is you can get it out, because it isn't stuck between the outer and inner vent grills.

Spadesluck MAY 24, 06:14 PM
I have thought about modifying my vents but I have not run into any heat problems with my car as of yet. I do have a bigger 3 row aluminum radiator, the fan never comes on unless I am using the AC
ag9123 MAY 24, 06:28 PM
I use the 85 vents in the summer on my 84 Indy.
So it's ventilated all the way across the engine compartment.
Definitely helps get the heat out...

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1984 Indy Fiero

[This message has been edited by ag9123 (edited 05-24-2019).]