Just wondering if anyone has swapped out the original Fiero blower motor with a newer one such as the S10 mod. for brakes. I find that on both my 88GT and my sons 87GT, the blower works as best I can tell like it was designed, but when comparing against newer cars, they lack enough volume and pressure unless you are in the A/C high mode of operation. I haven't taken one apart to try and see if a better motor option is available but I suspect maybe a blower motor from say a 90 to 91 Firebird, citation? or some other bigger vehicle might fit in place and deliver more air. What are the Fiero communities/ tinkerers thoughts on this?? Curtis
I have been wondering that myself. I was planning to mod the fan motor resister to see if that would work but haven't had time to tinker with it yet. Input would be much appreciated.
If you find debris on the resistor wire it would benefit you to also look in there real good to see as much of the evaporator as you can. I pulled my resistor piece to see if I could see any debris and after seeing some and pulling the evaporator coil this is what I found. Mike
[This message has been edited by Patrick (edited 07-18-2016).]
No I haven't done that, but I will explore if their is a fairly easy way to inspect the box via a scope my brother owns, any input on the easiest way, or most likely place to search for obstructions would be appreciated. I have replaced the heater core on the 88GT and did not find any debri when it was apart though. Curtis
I have replaced the heater core on the 88GT and did not find any debri when it was apart though.
Doesn't air go through the A/C evaporator (pictured above) before it goes through the heater core? Perhaps the air reaching your heater core has already been "filtered".
[EDIT] I looked up my own thread to answer my question. Yes, it looks like the heater core is indeed behind the A/C evaporator.
[This message has been edited by Patrick (edited 07-18-2016).]
The evaporator core is ahead of the heater core, but the airflow is completely separated when the A/C or Heater is at full function. Only when the temp settings are at less than max for each are they mixed. The blender door separates airflow from the two cores when the A/C is on and begins to allow airflow to pass over the heater core as the temp control slider is moved toward HOT.
The evaporator core is ahead of the heater core... when the temp settings are at less than max for each are they mixed.
So, in that scenario does the air go through the evaporator before it goes through the heater core, or is the air mixed after some of it goes through each component?
Along the same lines... in Defrost mode (the A/C is always on), what is the route the air takes through the HVAC unit when the heat is turned up full?
I have to admit that I've never paid much attention to the inner workings of an HVAC unit. I removed all A/C components from my Formula and basically erased all knowledge of it from my memory banks.
[This message has been edited by Patrick (edited 07-18-2016).]
The air always passes through the A/C core regardless the mode. If the A/C isn't on, the core is just there. The blender door is what controls the temperature. That's operated by a cable from the slide control at the dash. The Defrost/Vent/Floor discharge is controlled by the electric servo motor underneath the dash. If the A/C were on, the system is always cycling and will chill to the maximum of it's capability. If there is no air flow over the core, it will eventually ice over, so there must be air moving over it at all times to remove the moisture buildup.
The air always passes through the A/C core regardless the mode.
I thought this was what I had said earlier to the OP... and then I appeared to be corrected. What am I missing here?
quote
Originally posted by Patrick:
Doesn't air go through the A/C evaporator (pictured above) before it goes through the heater core? Perhaps the air reaching your heater core has already been "filtered".
Getting back to the original question: Anyone changed out the stock Fiero A/C, vent, blower for a newer more powerful one?
Not necessary at all. If A/C and blower motor are working properly it should have sufficient cooling power. My R-134a conversion works so well it actually gets too cold in there. Why try to reinvent a system that works.?
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
Getting back to the original question: Anyone changed out the stock Fiero A/C, vent, blower for a newer more powerful one?
Not necessary at all. If A/C and blower motor are working properly it should have sufficient cooling power. My R-134a conversion works so well it actually gets too cold in there. Why try to reinvent a system that works.?
I have to agree - I get lots of "wind" from my OEM blower motor as well as making it too cold.
In answer to the OP question...yes, I've changed my complete system to that of a 2004 Grand Prix system. ...but you definitely don't want to go that route!!! If you were to just change out the blower motor (which is sufficiently powerful), you'd likely need to upgrade the motor controller as well but that isn't directly compatible with the Fiero HVAC control.
It may take me a week but I will investigate and try to find out why my 88GT is so poor for flow unless I am in the Max A/C mode. It could be just bad resistors, some unknown restriction or just a bad blower motor.. I will let you all know. I have never had the problem of too cold with the A/C on, I wish I had that kind of problem.... Curtis
It may take me a week but I will investigate and try to find out why my 88GT is so poor for flow unless I am in the Max A/C mode. It could be just bad resistors, some unknown restriction or just a bad blower motor.. I will let you all know. I have never had the problem of too cold with the A/C on, I wish I had that kind of problem.... Curtis
Or leaking ducts. If the vent doors aren't sealing properly, air won't go where it's supposed to. Yes, you "can" go with a more powerful blower motor, but that's not the problem unless your motor is failing, in which case you just need a new motor.
It's like wanting to put a bigger AC unit in your house because it's not cooling before you check to see if all the doors and windows are closed.
It may take me a week but I will investigate and try to find out why my 88GT is so poor for flow unless I am in the Max A/C mode. It could be just bad resistors, some unknown restriction or just a bad blower motor.. I will let you all know. I have never had the problem of too cold with the A/C on, I wish I had that kind of problem.... Curtis
Have you pulled the blower motor and inspected the squirrel cage fan. I pulled out one where a mouse had built a nest in it. After all the crud was removed the motor blew as strong as new. Also check the blower motor resistor and the speed of the motor by applying direct 12V battery power to it. Does it sound like its turning fast on the A/C max setting with the fan turned all the way on high?
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
A couple questions, does anyone know the correct resistances I should have on the blower resistors? Also, in searching for a possible new blower resistor replacement, I have had trouble finding a source for a new replacement, the typical Autozone, Carquest, O-reilly, TFS, don't list them. Is this a dealer item? Is another one from say a 1988 Firebird the same? I found those available at rock auto but none for a 1988 GT.. Curtis
[This message has been edited by Curtisk1060 (edited 07-22-2016).]
If you're not satisfied with the air velocity from the vents I understand. If you are also under the impression that you can obtain cooler temps with higher velocity (and volume) from the vents with a more powerful motor, you are not going to achieve cooler air in the end. You will be attempting to cool a greater quantity of air with the exact same evaporator output which will result in warmer vent temps. You can test the theory now with a thermometer which should demonstrate the coolest temps at the lowest fan speed. I've been some what dissatisfied with my A/C performance which despite acceptable vent temps still feels like it is under performing. After giving it thought, I realized some improvement can be had by installing what some cars come from the factory with, a bypass fitting that completely routes engine coolant past instead of through the heater core when the A/C is in use. A near 200 +/- degree heater core has to radiate a good bit of heat that is off setting some of the cool air given its proximity to the vent and evaporator.
If you're not satisfied with the air velocity from the vents I understand. If you are also under the impression that you can obtain cooler temps with higher velocity (and volume) from the vents with a more powerful motor, you are not going to achieve cooler air in the end. You will be attempting to cool a greater quantity of air with the exact same evaporator output which will result in warmer vent temps. You can test the theory now with a thermometer which should demonstrate the coolest temps at the lowest fan speed. I've been some what dissatisfied with my A/C performance which despite acceptable vent temps still feels like it is under performing. After giving it thought, I realized some improvement can be had by installing what some cars come from the factory with, a bypass fitting that completely routes engine coolant past instead of through the heater core when the A/C is in use. A near 200 +/- degree heater core has to radiate a good bit of heat that is off setting some of the cool air given its proximity to the vent and evaporator.
True many cars I have been in cool best when the fan isn't on high. Its kind of a rig but I also have bypassed the hot water flow to the heater core on quite a few cars due to faulty doors that allowed the heat to mix, and cars without AC that allowed hot air to flow thru. What part/valve did you use for a Fiero?
[This message has been edited by 2.5 (edited 07-22-2016).]
Originally posted by 2.5: True many cars I have been in cool best when the fan isn't on high. Its kind of a rig but I also have bypassed the hot water flow to the heater core on quite a few cars due to faulty doors that allowed the heat to mix, and cars without AC that allowed hot air to flow thru. What part/valve did you use for a Fiero?
It's on the "To do" list however I have an "H" shaped valve that I intended to use for something else until I received it and discovered that it was not a manual valve although the knob makes it look like one. I've had it sitting in a box for a few years not giving it any thought for use for the purpose it was designed until now. Here's what it looks like:
AC Delco 15-5675
There are a number of different types, I don't have mine close at hand at the moment and it was intended to be used as a manual bypass for my liquid air intercooler for preventing an ice water mix from being run through the heat exchanger which would warm it up faster.
[This message has been edited by Joseph Upson (edited 07-22-2016).]
Just an update on what I found so far.. Removed the blower motor and found it just a bit dirty, found no leaves, mice, or anything other than a bit of caked on debri on the lower portion of the evaporator I could see from the blower opening, the rest of the box was just slightly dusty. I then removed the blower resistor assembly and I was able to see more clearly the debri, which was mostly on the bottom row. I then cleaned it off with a brass wire brush through the various openings, I also vacuumed out and blew it out the best I could. The blower motor was original and turned freely so I just cleaned it up, lubed it, and re-installed it. I tested and didn't notice any huge wonderful difference from before but I will try it the next few days and see if it made any improvement. This past weekend I went on a cruise with the Mile High Fiero Club and I compared my blower output against a nearly perfect low mileage 88 Red GT and I believe the output of both of ours is the same. The owner agreed with me that the 80's technology just isn't as good as current vehicles and he also felt the blower output just never was enough for these cars compared to today's vehicles. In the future I will take the time to completely tear apart the blower assembly and see if I am missing some type of blockage. My only other option would be to try and purchase a new blower and see if it makes a difference but for now I will just live with it. Running it on max. fan works for me. I am going to several more shows this summer and I will compare mine to the other Fieros in attendance. I still may try to find a stronger blower to retrofit in the future. I guess my original question has never been attempted for anyone trying to find a higher output blower that would easily retrofit. I would like to be able to feel more air flow in the low range and then of course all the way up, as it is, I only feel a sufficient flow when in the max. fan speed mode no matter with or without A/C.. Curtis
[This message has been edited by Curtisk1060 (edited 07-25-2016).]
The owner agreed with me that the 80's technology just isn't as good as current vehicles and he also felt the blower output just never was enough for these cars compared to today's vehicles.
I dunno, I kind of doubt that blower technology has changed a whole lot in the last 50 years... but I could be mistaken.
I've had four daily driver Fieros... an '84, '86, '87, and '88. The blowers in them all seemed to be pushing plenty of air, especially with the cabins being so small.
[This message has been edited by Patrick (edited 07-26-2016).]
But.. I have no AC right now (working towards that, original R12 system never repaired). I am roasting in this heat. So I notice that when moving, by 2-55 AC system works fine (2 windows 55mph). But at a standstill, the exhaust header being about 8" from my back, I begin to cook like a lobster. Is it possible that it is just a matter of feeling all of the heat from behind, and believing that the HVAC is not good enough? A temporary slice of insulation behind the seat might be a good test to see if it is an issue.
I've had four daily driver Fieros... an '84, '86, '87, and '88. The blowers in them all seemed to be pushing plenty of air, especially with the cabins being so small.
Same here, Fiero Blower always more than adequate for me. I never run the blower on high. Now COOLING is a different story. I've had many Freon leaks over the years and had many times when A/C wasn't cooling due to low freon level. Even when the car was little more than a year old, I recall going into PepBoys a buying a single can of freon to top off the A/C.
If your compressor is on and your fan is blowing the AC is doing all it can do, which is sufficient in most cases - Qatar, I don't know.
What color is your car? Anything other than white or very light will give a LOT of radiant heat if the sun is out. I have a black SE and in Central Florida the roof is HOT when in the sun. It doesn't matter if you're moving or not. Radiant heat, such as from the sun, does not respect airflow.
You can restrict or negate the coolant line to the heater, but if the Heat/AC doors are working it won't make any difference, except your thermostat opening temps will be really weird. Don't ask.
If the evaporator and the condenser are clear and the compressor is engaged the AC is doing all it can do. The stock system is sufficient for everything except aging beef, and in the shade maybe even for that.
If you have a sunroof and are south of the Mason-Dixon line you are going to have a warm head in the summer sun. Insulation helps, but little, against radiant heat. BTDT. Paint the roof white.
My cooling temperature from the A/C is fine, by the way my car is yellow. However, I just want to have more air volume at low, medium, etc. in the vent mode or in A/C mode. It just lacks sufficient flow in my opinion. It gets plenty cold over time, even in the sun but I just want to feel the flow more than I do. Maybe its a product of my higher altitude? ( 5800 ft. elevation) and no humidity which makes it seem less than others on the forum at sea level with lots of constant humidity..
Back in the summertime, my heater core started leaking. I didn't need the heater at the time, so while I was tracking down a new core, I bypassed the leaking heater core by disconnecting the two rubber hoses from the core and re-connecting them to each other. However, between the two hoses I used a fitting which had a very small passageway for the coolant to go through. When I got the new heater core, I flushed out my system and I was very surprised at that time to discover my thermostat looked much like it does in the picture above. I didn't understand at the time what the heck had happened to the thermostat, so I just bent it back into shape and re-installed it. Unknown to me until the cold snap here revealed a problem, the thermostat arms bent again from "normal" water pressure in the system (because the thermostat "arms" were now weak from being previously bent).
So in retrospect it's now easy to figure out what happened. The fitting I used to temporarily connect the two heater hoses to each other restricted the coolant flow way too much and this resulted in higher than normal coolant pressure pushing against the thermostat. The long thermostat "arms" therefore bent.
Originally posted by cswillson: You can restrict or negate the coolant line to the heater, but if the Heat/AC doors are working it won't make any difference, except your thermostat opening temps will be really weird. Don't ask.
What about the effect of the radiant heat given off by the heater core to the surroundings in that area of the dash which should work the same as the old radiators used to heat rooms.
quote
Originally posted by Patrick:
Not a good idea!
[QUOTE]Originally posted by Patrick in This thread:
Back in the summertime, my heater core started leaking. I didn't need the heater at the time, so while I was tracking down a new core, I bypassed the leaking heater core by disconnecting the two rubber hoses from the core and re-connecting them to each other. However, between the two hoses I used a fitting which had a very small passageway for the coolant to go through. When I got the new heater core, I flushed out my system and I was very surprised at that time to discover my thermostat looked much like it does in the picture above. I didn't understand at the time what the heck had happened to the thermostat, so I just bent it back into shape and re-installed it. Unknown to me until the cold snap here revealed a problem, the thermostat arms bent again from "normal" water pressure in the system (because the thermostat "arms" were now weak from being previously bent).
So in retrospect it's now easy to figure out what happened. The fitting I used to temporarily connect the two heater hoses to each other restricted the coolant flow way too much and this resulted in higher than normal coolant pressure pushing against the thermostat. The long thermostat "arms" therefore bent.
Lesson learned!
Pinching off and or significantly reducing flow in the heater circuit cuts off the by-pass flow from the water pump (that pipe sticking out the top) until the thermostat opens. A symptom of my coolant system being partially frozen over during a freezing KS day was the engine revving like a formula 1 car where the rpm came down very quickly as a result of the back pressure on the pump working like a brake.
A substandard aftermarket blower motor may be the cause of the seemingly weak airflow.
[This message has been edited by Joseph Upson (edited 07-28-2016).]
Did you clean all of the fuzzy crap that collects on the fan blades? That can have a large effect on the fan's output. Also ensure (if you haven't already done so) that the area in the cowl that the fan pulls from is clean as well. Reduced input = reduced output.
I drove my black Fiero for years and never had a complaint about the AC or the heat. It cooled equally well with R-12 and R-134a. Out here we get temps in the mid to high 90's with high humidity on a regular basis (like for the past 2 months).
Good luck!
------------------ 1986 SE Aero coupe.
3.4 DOHC swap is complete and running, now just have to finish the rest of the car...
Yes, it looks like the heater core is indeed behind the A/C evaporator.
What am I missing here?
If you were to just change out the blower motor (which is sufficiently powerful), you'd likely need to upgrade the motor controller as well but that isn't directly compatible with the Fiero HVAC control.
