Judging interest in group buy

[av8r4aa]

I talked with a AC specialist today. He is very familiar in the
BMW 6 series AC systems. I asked about his company making a
parallel flow exact size new condenser . I am going to send him
my spare tube-and-fin condenser. He said that he can duplicate the exact size, exact same mounting, modern Parallel flow condenser.

The biggest drawback of these older systems is the ancient tech.
tube and fin condensers. They are just very inefficient and cool
poorly.
I am convinced that with a decent condenser these cars CAN be cooled
down and driven in comfort.


These will be also set up to use our Bosch 2 speed factory fans.
The price for one was quoted near 400 dollars.

I asked about making 10 of these for our 6 community.
He said the price goes down considerably with more copies.

What is the general interest in these condensers.
I don't ask for cash up front, just taking a general survey.

Would you be interested in buying one for your car?

[FernandoBunster]

I would be very interested in a group buy if it would do the trick with my 134a converted system.

[kbert777]

I am not really convinced that a more modern condenser will produce that noticeable of a difference in the output of our A/C systems.

I am in Las Vegas, where we have quiet a few 120ºF days over the summer. I am still achieving low to mid 40's center output temperatures in these conditions, using stock condenser and evaporator, Sanden compressor and virgin R12, auxiliary fan running on high.

The main problem is the very insufficient airflow over the evaporator due to the piggy-back design of the factory dash air systems. The later systems with rear evaporator at least guarantee a nice and cold right elbow, unfortunately the factory system lacks a decent mechanism to distribute coolant flow between front and rear evaporators.

Before I would embark on the mission to improve the gas side of the system, I would strongly recommend replacing the A/C blower motor, fixing all the underdash ducting, insulation and sealing, replacing the sealing foam on all the blend and fresh air doors.

A more modern, efficient design condenser would be of benefit if you insist on converting to R134a, but a lot more steps and costs are involved in a correct and lasting conversion compared to a simple R12 charge. An improvised, quick R134a conversion might work in areas of the country where you would not need a functional A/C system in the first place, I would not recommend or consider it in areas where you depend on a reliable A/C system.

If the cost of R12 is a deterrent, we offer our customers the alternative of modified refrigerants, I prefer Freeze12, have been using it in several of our vehicles for almost 10 years. The common argument against modified refrigerants is that they are almost completely R134a based, with minor additives in order to make them compatible with mineral oil and to adapt the pressure and cooling characteristics to mimic R12 as close as possible.
Keep in mind that these modified refrigerants still require barrier hose as replacement of the stock hoses, so some custom fabrication is almost certainly required.

Klaus

[Layne]

I might be interested... I had not planned to convert to R134a, but if I can make it as good as an R12 system, I'd be interested. We would need to check if all E24 condensers are the same, I'm not sure. I know there are variations in the tubing etc. Also, I think there's room to make them thicker. Besides the more efficient design, and additional thickness you can work in will make them work better.

[av8r4aa]

I also want to use a Sanden compressor. The Bosch is very noisy
and old technology. I have a lot of R12. I agree mostly with Klaus.
For sure, ducts need to be resealed and the rest of the system brought up
to modern standards. The rest of the AC system works and I really
believe that a new condenser will improve the system considerably.
I do not want to run my condenser fan at high setting all the time. It is way to noisy
and draws a lot of power. Just get a new condenser and you are basically doing the same thing.
I have heard that R12 will work well in a parallel
flow condenser. My 86 and 87 both have the rear AC.

[av8r4aa]

Hey 6 guys,
I sent my condenser and my Bosch blower fan to the AC company.
I will report back with the prototype aluminum condenser.
It will be a custom built, direct fit, parallel flow, 134a and R12 compatible
all aluminum, welded condenser. I am expecting much better slow speed
cooling and much lower head pressures. From the research I have
done, I feel that we can have a 6 series car that will be drivable and
comfortable in the upcoming hot months. I also think that the cars
with just the single front AC will benefit greatly from the improved condenser. The heat dissipation difference between the BMW stock
tube-and-fin and the newer parallel flow condensers is above 30 %
better improvement.
I have requested that it be the exact same mounting points and the
Bosch fan MUST be mounted as the original.
I have asked for a price on 10 of these made. I am waiting
for a quote so let you people know the price.

I am getting 2 of these made, One for my M6 and one for my 635CSi

[///Malcontent]

Along with other AC system component upgrades, has anyone upgraded the heat and AC blowers with newer, more powerful or more efficient units? A squirrel-cage blower is a pretty standard part but surely something newer/better can be substituted.

[av8r4aa]

I have had the complete AC system componets on the
bench and have looked every part over. The blower fans we
have are fairly decent. Bosch makes good motors and squirell
cage fans are the most efficient method to move air
I sealed the ducting so there is no blowby. My research
has showed our worst AC componets are the ineffective
condenser followed by the Bosch compressor. I want to
change out to the Sanden compressor and the new
condenser. For everyone that driven in a newer Asian
car lately those AC systems work great.
They have larger parallel flow condensers.