LS6427

iTrader: (2)

I think the factory ram air has better air flow pushing ambient air up and then through the condenser, and then through the radiator, and then passed the fan blades (not spinning). Rather than the ram air hitting an obstruction to begin with, then getting passed the fan blades, causing the air flow to be disrupted and causing eddies everywhere.......then going through the condenser and radiator. It just wasn't designed for the air to hit an obstruction first. It was designed for the fan blades to be (not spinning) and in the back...
I think the factory smooth air flow up and then through them works much better......
Plus the factory shroud is hard to beat with pusher fans.

I have seen some badass sheet metal shrouds though....but how do we know they really work like a factory tested and designed shroud....maybe they are horrible and really getting air through it smoothly....

Who knows.....

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LS6427

iTrader: (2)

Interesting.....

So the heat thats coming off the condenser, engine side.....where does it go?

Is it completely separate from the air coming up from the air dam and hitting the radiator?

What mounting bracket is that?

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JakeFusion

iTrader: (7)

That is interesting.

dlandsvZ28

It goes into the cavity behind the ac condenser and stops at the plastic shrouding that encapsulates the radiator. I don't have any wind tunnel so can only assume some air goes into the engine bay and down to the ground and some perhaps into the mix captured by the front air dam and the puller fan on the rear face of the radiator (if it is running, which unless in very cold ambient times of the year, is most of the time).

So the radiator system is NOT 100 percent isolated from the ac modification. However, the ac condenser is isolated from the radiator. All air to it comes thru the front bumper cover (first thru the fmic and then to the fans on the front face of the huge ac condenser). So the air to the condenser is partially heated as a result of passing thru the fmic first. The air to it is NOT 100 percent ambient.

However, IMO, the slight increase over ambient is offset by the force of the SPAL pusher fans forcing air thru the condenser compared to the ram effect of the air from the dam and draw of the air from either the stock or aftermarket puller fans - especially so in slow moving traffic or when stopped at stoplights.

With the stock confirguration IMO it's when the ac is on and not getting much air from the air dam that there isn't enough air passing thru the condenser and that which does is heated to at least 150 degrees. And where does it go - straight to the radiator?

In effect we are expecting the radiator with a 185 tstat to draw heat out of the engine coolant with air that is as high as 50 degrees or more over ambient.

With my configuration the air thru the radiator is unrestricted by the ac condenser. As a result the puller fans are more efficient because there isn't any restriction and the air is much closer to ambient.

As for the mounting bracket. It's my 7th version.

I started with a Midwest Chassis bumper support. However I couldn't fit the fmic and condenser inside the confines of the tubing. Plus the tubing in the front took about an inch of clearance. Every 1/2 inch of clearance was measured and remeasured in order to get it reasonably right so each would fit.

However, not to dis the bumper support. It will work great with just a 26 X 12 X 4 inch fmic. However with my configuration the fmic has to be forward as much as possible causing the lower tube on the brace to be directly in the way of the fmic inlet and outlet. The fmic can only be so high or so low in order to fit into the front cover. In addition I wanted the intercooler piping to be above the bottom of the bumper cover and also above the covers that attach to the bumper cover in front of each wheel. I currently have hacked the plastic covers, but will replace them with aluminum covers with opposed inlets like the stock pieces.

I made the white bracket as I was learning how to mig weld. It's not pretty, but it works. This winter will replace it with a single aluminum bracket on each side very similar to the brackets that ATI supplies with their fbody fmic kit. The fmic and the ac condenser will attach to each aluminum bracket from the side totally eliminating the piece the fmic hangs on now. Obviously the brackets will be slotted so the fmic and condenser can be moved up or down to a 1/4 inch since space up and down and fore and aft is so critical.

The side brackets will also allow much better placement of the alky control pump and also space for a small washer tank on the passenger side. The stock washer tank holds the methanol. The brackets will also allow for a larger longer air filter (see link) even though the current one is very large.

Back to the radiator and single ATI fan. I do have the first version of the Spal extreme 16 inch fan, but it is limited service unlike the extreme that replaces it. So far the single ATI fan and stock auto radiator is keeping things cool.

Also I think a narrower radiator can be moved forward quite abit since there no ac condenser in the way and/or reroute the electrical wiring that is in the way on the passenger side with the stock width radiator. Moving the radiator forward might allow the stock fans to be reinstalled. Moving the radiator forward would also aid in getting hot air out of the engine compartment. Slanting in downwards helps too as opposed to straight up.

How nice to drive in temps north of 100 degrees and not worry about overheating with the ac on while at the same time have a more efficient ac system (42-43 degree at the outlets). Now need to get me some sunshades for the t-tops.

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So how about the IAT's from the fmic - the alky control pump manages those when in boost.

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Lastly, not to brag or bring up the past, but there were a ton on naysayers who poked fun of my idea back in 2005-2006 to add a second puller fan to the ATI shroud to aid with overheating. Now it's pretty much accepted.

Never did make much sense to me that ATI closed off the hot inlet side of the radiator and out of necessity had to place the 16 inch fan at the coolest side of the radiator (unlike the stock fan placement - high side fan on the left and low side fan on the right).

LS6427

iTrader: (2)

Yea, the idea of all the ram air being used for the radiator is the key. Than whatever can be done to cool the condenser wherever its mounted should be sufficient for the A/C. Especially with a constant running fan.

I'm using a Bell 4.5" FMIC......not sure if I'll have room behind it for fans and a condenser......in my Trans Am bumper.

Unless I use two separate condensers running in series......then they can probably find a home with a fan on each. Thats if condensers can run in series and work.....

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01ssreda4

iTrader: (96)

Basic physics just dont work that way. First, the fans do spin (passively) while going down the hwy. Picture this, as a UNIT, the condenser (restriction), the radiator (restriction), and non-running fans (restriction) packed together, sealed, as one piece, will stop airflow equally forward or backwards. Again, air does not care, its a fluid moving through 3 restrictors at a certain velocity.......with the exception of shrouds with those flapper thingys which would not work reversed.

dlandsvZ28

Don't know the configuration of your Bell 4.5 fmic but if it is similar to the Mishimoto 4 inch fmic I use shown in my link, then an ac condenser will fit behind it including the fans if you remove the stock washer tank and find a new home for it. That's assuming you are using it for either a washer tank and/or methanol tank.

A washer tank on the driver side is not an issue nor is the methanol tank if you move it to the rear of the car.

Note: there is a lot of trimming/cutting that needs to done to the front bumper cover so if you want to keep the bumper pristine that's another issue to consider.

What I had to do over and over, is remove the front cover and then lay the fimic inside the cover to determine the open space on the rear of the fmic, then calculate space needed for the condenser and fans. Not as easy as it would seem and why it took so many versions to get it right.

The bottom edge (fmic and condenser) can only be so low and the top edge can only be so high. In particular, the condenser because it is the tallest of the two. You don't necessarily need a 28 x 16 condenser and you can use the stock condenser - about 26 X 16. If you use the stock condenser, IMO remove and replace the in and out fittings with AN fittings. So easy to attach and remove and less susceptible to leak - 6AN on top and 8AN on the bottom.



As for the Firebird front bumper cover, there might be space considerations between your headlights and their mechanism to open and close compared to the Camaro headlight mounting brackets. I had to measure twice and cut twice many times to get it right on my Camaro.

Cold Hose is your friend when you lengthen the hoses. Excellent service and reasonable prices - less than $100.

As for china made condensers, the 28 x 16 from a vendor in IA came pressurized, sat in my garage for two months, and was still pressurized when I mounted it and pressurized the ac system - unlike a new Spectre stock style condenser that arrived unpressurized. So didn't know if it would leak or not until I charged the system.

I didn't use the new Spectre because it was going to cost more to remove the high and low side hose ends and replace with an fittings than the cost of the 28 x 16 condenser ($125 an hour for aluminum welding locally).


As for the fans on the condenser running constantly, they do now controlled by an on/off switch located on the mounting bracket driver side.

Vintage air has what is called a trinary switch. I might try it. No need to run the condenser fans in the cool months of the year if not using the ac or simply use a remote to control the fans like the remote on my 12 Corvette GS that opens and closes the dual mode exhaust.

https://www.vintageair.com/tech-vide...rinary-switch/

Yes - one can install the manual switch inside the cabin, but IMO just more wire to run into the cabin that is already space limited for a place to mount - 4 extra gauges, line lock, alky control etc etc.

dlandsvZ28

There are ten of thousands of autos and trucks that come from the factory with ac condenser fans. Some are pusher and some are puller. Some are dual purpose and some are isolated from each other (Dodge Ram 1500 for example where the ac condenser is isolated from the radiator).

IMO the isolated systems IMO work the best and are the most efficient especially for the radiator cooling system.

The Ram 1500 is a puller fan with a very good shroud. I think a puller with a very good shroud is more efficient because the shroud allow the fans to pull from the entire rear face of the ac condenser whereas a pusher fan, even with a shroud, will mostly blow air thru the condenser only on the face of condenser where the fan is mounted even if it is mounted with a space between the condenser and rear of the fan housed in a shroud.

As for a restriction because of the fan housing (shroud), I think the restriction is mostly offset because the fan is drawing air thru the housing. Try to hold 12 or 14 inch puller fan in your hands if you don't believe the suction they have even if they are a pusher -especially a Spal.

As for my configuration., I could have installed Spal pullers on the AC condenser instead of Spal pushers but I would have had to remove the washer tank. I use it for the methanol tank, but it could be moved to somewhere else for those who want to try puller fans instead of pusher fans.

However, with the puller fans on the back of the ac condenser would there be as much draw to pull air thru the fmic? I think not.

The fmic doesn't need any assistance with air flow because it get a straight shot of air thru the front bumper cover (if the car is moving). If it's not moving or moving slowly then IMO the pushers assist in air movement with a plus in that the pushers slows down heat soak on the fmic as well in slow moving or stopped traffic.

But I'm just a dumb very old farm boy (70). What do I know? It works for me and that is all that is important.

01ssreda4

iTrader: (96)

We have a Durango, Im familiar with the isolated condenser fan setup. I will slightly disagree with the "Straight through air" in the front bumper though, due to before i was T/C, i thought it would be a great idea to move my trans cooler (no fan) off the condenser and cut a hole in the bumper and mount it similar to an intercooler. It failed miserably. Temps went way above the norm i was used to. It became almost completely fan dependent at that point (once i added one). It made sense to me that it would work, and it simply didnt not. I believe the car splits more air naturally then it wants to engulf.

LS6427

iTrader: (2)

You fit the condenser behind your FMIC and you kept the factory washer fluid tank. I could take mine out and just relocate a tank where the coolant over flow tank is located. That should give me plenty of room to do what you did.....I think....

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dlandsvZ28

Yes- if the washer tank and hood mechanism is the same as that on a Camaro.

As you can see in the pic, if the puller fans are located on the rear of the condenser, then you can move it forward 2-3 inches offsetting the width of the low profile puller fans that are just a tad wider that 2 1/2 inches.


However, if you look you will notice that the plastic shrouding in front of the radiator blocks air from the pullers or pushers on the condenser as it exits the condenser. The air flow goes up or down, so the buffeting effect of pullers on the rear will be more pronounced then pushers on the front. So IMO I would use pushers and simply move the ac condenser back an inch offsetting the 1/2 " extra width of your fmic compared to my 4 incher. This assumes, however, that you can mount your fmic as far forward in your bumper cover as in a Camaro bumper cover.

You will have to trim part of the bottom of the plastic shroud, else there is no where for the discharged air from the condenser to go. I assume the air dam will catch some of it as the air finds it way up to the radiator. Even so the pullers on the radiator will more than compensate because of the removal of ac condenser.

To calculate the width of the condenser, measure the distance between the frame horns. I recall a 26 inch wide will fit dependent upon how you build the two supporting brackets. A 14 inch tall condenser is the ideal height, but I couldn't find a 28/26 X 14 inch universal ac condenser. Plus in KS I needed all of the surface area I could use because of our extreme summer temps, so I opted for a 28 X 16 X 7/8 inch.

BTW, there are more options from Spal for 12 or 14 inch pullers than pushers.

LS6427

iTrader: (2)

Yea, getting that condenser away from the front of the radiator is the key. I mean when we all sit in traffic on a hot day and the temps start to creep up....as soon as we turn the A/C off.....the temps come screaming down fast....start moving just a little and they drop like a rock. I can;'t imagine having nothing in front of the radiator......

Can probably stick with a factory radiator in that case....but I want to get away from all the plastic.

Do you know if two 13 x 13 condensers connected in series would work for an AC system.....or does the condenser have to be one unit....?

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LS6427

iTrader: (2)

dlandsvZ28,

I wish I knew how the Trans Am front bumper and Camaro bumpers differed inside.....I guess my turbo kit installer will have to see when he takes it off.....

I ask about the two separate condensers because I have room to put two 13 x 13 condensers, if they are run in series, at angles up front away from the radiator......each with 12 x 12 fans on them. If condensers will work in series.....this can work also.

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dlandsvZ28

I think if you run two condensers that you would have to design your system like those that run a front and rear ac system (Suburbans etc). Just a hunch, but it would seem that with a parallel system the freon would be chasing itself as it flows from one condenser to another. Might want to post your question in another forum on this site and get an opinion from a pro ac tech.

Cost wise I think one condenser is much cheaper that trying to fabricate two together running parallel.

Tip: I tested first with cheap components (condenser and fan's for example). After confirming that it was going to work, then got a better condenser and Spal fans (about $360 - 2 Spal fans, condenser, AN fittings and hose).

If you run two aftermarket fans on the radiator and another two fans on the condenser(s) - lots of amps when they engage. I am currently running the 16 inch ATI fan on the radiator and two Spal fans on the condenser.

BTW - an Escalade 145 amp bolts right on so wouldn't think you would have any clearance issues with a turbo setup. An Escalade 145 won't work with a Procharger because the alt pulley touches the bolt holding the charger pulley on the head unit. The 145 amp alt is wider (circumference), as a result the pulley on the alt isn't in the same spot as it is on a stock alt.

Still in the works -I think I will have to move the alt topside if I want to upgrade to a 145 amp alt.

LS6427

iTrader: (2)

I just got a reply from an AC expert.....its like reading Chinese.....

He said it will work, but I must have the first condenser to have larger tubes on the inside, and smaller internal tubes inside the second condenser.

Look at this:

Condenser Basic Design Principals:
A single condenser installation can be analyzed as 3 heat dissipators in series.
1) Initial heat disippator #1: Large internal flow flow cross sections for SENSIBLE heat transfer of superheated high vevocity gas only. (Ref "How to Air Condition Your Hot Rod" pg. 16 Cool Science Concept 8 : Latent Heat; available from Vintage Air). Gas gives up it's superheat with temperature reduction.
2) Mid heat disippator or actual Latent condensing section #2: Gradually reducing internal flow cross sections to optimize refrigerant velocity as LATENT heat transfer occurs and warm gas becomes 100% warm liquid with no basic temperature change.
3) Final Sensible heat transfer disippator #3: Temperature change is effective to cool Warm liquid as subcooling occurs and liquid becomes colder than the liquid exiting the condenser section (#3).
Now the first decision is series plumbing verses parallel of a 2 condenser A/C system?
I choose a series design because :
1) Was building a optimized custom system with minimal plumbing connections and weight/cost.
2) Would build the first heat X with the first 1/3 large multiple flow path for basically gas volume only and gradually transition to fewer flow paths as gas condensed to liquid.
3) Second condenser would have less cross section initially transitioning to a small crossection at the outlet for subcooled liquid only.
Converesly, if you go with off the shelf condensers then parallel flow is optimal.
I didn't want the unbalance of all of the 5% oil clogging one parallel circuited condenser and not the other and to avoid one heat X exiting some gas while the other heat X exited over subcooled liquid so series layout was used.
So your on the right track if the first condenser has larger flow cross sections than the downstream second condenser in an efficient manner.
If off the shelf convensional condensers are used then parallel is the best option because most condenser types have smaller flow areas approaching the outlet and this restriction on refrigerant which is not yet half condensed into liquid is unacceptable for flow restriction when used 2X.
Concerning system balance the condensing capacity should be approximately 130%of the evaporator capacity due to the heat equivalent of the compressor power input.
But condenser capacity is very dependant on air flow and fan ratings are dubious. A shrouded fan which utilizes the entire condenser is preferred.
Reminder: For high rev engines choose a compressor drive ratio that complies with less than the compressor rated crpm
Hope this helps,
hotrodac
__________________________________________________ _______


Another idea.....
Cut away my entire hood latch assembly and just use hood pins to lock my hood down.

Then I can move the radiator forward 3-4 inches. Leave the factory puller fans in place........then put two pusher fans on the front of the condenser....
That could be sufficient air flow.....

If my installer can do what you did....I'll do that instead.

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dlandsvZ28

You might check with Vintage air. Rather than reinvent the wheel perhaps they already have a custom configuration that includes two condensers.

https://www.vintageair.com/

BTW, I actually tried two pusher fans on the ac condenser while it was in the stock location. They worked great until summer temps shot north of 100 degrees. Then the radiator just couldn't keep up and coolant temps would rise to 240.

So plan A didn't work.

You can move the stock radiator only so far forward if the condenser is removed because there is a large wire bundle in the way. To get the radiator to move forward more it will have to be narrower or one would have to reroute the wire bundle. This assumes you don't want to cut into the brace in front of the radiator.

Moving it forward enough, however, allows for enough room to reinstall the stock fans and shroud and still keep the radiator slanted backward.

Note - with a ProCharger - don't know about a turbo setup.

IMO the slant of the radiator backward is by design in order to pull and push the air expelled from the radiator backward and downward out of the engine instead of into the engine bay.

I just don't like hacking on the frame of the the car - especially in front of the engine. The only major modifications I have had to make is to the front bumper cover, the air dam, and lower splash shield covers on either side of the front bumper cover and the fenders.

I also had to remove the front bumper brace. I still might add a brace or tubing to tie the front of the frame ends together where the front bumper brace used to attach. I have room and it won't affect air flow.

MY_2K_Z

iTrader: (1)

Run the wire bundle across the bottom of the radiator instead of the top and you should have plenty of room. That's how I did mine. I cut off the entire front radiator support built a bolt in front end so I can remove it to easily work on the car.

LS6427

iTrader: (2)

Which wire bundle are you talking about?

I might try to cut into that top frame rail so the Griffin or Be Cool radiator will inset into it like so many people do....like 2 1/2" into that rail, then cut away the hood latch assembly so the factory condenser will still fit up front. Then attach the factory puller fans back on with the factory shroud.

Or maybe the two separate 13 x 13 condensers with their own 12 x 12 fans on each condenser running full time. But keep them more forward away from the front of the radiator so the ram air is all dedicated to the radiator.

Man...I guess its juts trial and error and what works for each set up....

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dlandsvZ28

The one inch wire bundle runs down along the bottom of the front of the battery, attaches to the lights etc on the passenger side and then over to the driver side attaching again to the lights etc. It's the end tanks on the radiator on either side that won't go past the wire loom on either side.

Some say the wire loom can be moved, but I don't want to cut and splice into any of the stock wiring - especially that wire loom. My 98 is nearly 20 years old now and the wiring is getting old and brittle. Don't want to create any gremlins by moving or cutting into it if at all possible.

That said, practically any modification is possible. Just depends upon your skill level if doing it yourself, or how deep you pockets are to pay someone else to do it. Paying someone to do it when it is still in testing or experimental can get very costly, however, if plan a or plan b doesn't work.

I have found that out doing it myself, even. Six fans of different sizes, three ac condensers, three radiators, three shrouds, three intercooler pipe systems not including the ATI 3 1/2 inch system, and three fmic's plus a lot of miscellaneous stuff. It adds up fast.

LS6427

iTrader: (2)

Well, that gives me more confidence......LOL.....Just kidding, thanks for all the honesty.

Almost makes me want to set up this whole cooling/condenser set up before the turbo kit goes in. Move the radiator as far forward as possible. Get the condenser in the bumper like you did with pusher fans (or the 2 smaller condenser idea), pusher fans on the radiator, and install the FMIC, and drive it around that way. Then install the turbo kit afterwards.

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