Anyone ever update their vent/AC system to 86+?

[Joeaksa]

I have a 85 model car and it has the tiny vents in the dash, with ever smaller vents on the outer side of the dash.

Was wondering the other day how much trouble it would be to mod the dash/car to the 1986 and newer vents that are a good 3-4 times the outlet size?

Anyone ever do this and if so how much trouble was it? Sure would be nice to have more airflow.

Thx,

joe

[Neel]

I wouldn't try to modify your dash, it can be done, but.. Look at the Griffiths website.. He has vent kits for early cars.. I'd look at his high speed blower kit, first.. We've used his products with great success.. Give him a call.. He is knowledgable and easy to talk to.. I believe he is a Pelican too.. To paraphase an old friend of mine:'cold costs money, how cold do you want to be?'
Griffiths supplies a range of air conditioning components for your Porsche 911,911s,911t,911 turbo, and 930, such as: Porsche air conditioning upgrades, Porsche air conditioning improvements and updates: Porsche barrier hoses and hose sets, Porsche c

[LWJ]

Hello,
I have an 80. The vents are tiny as you mention. However, I have factory AC with the front and rear condenser. The AC works fantastic (even with the huge York compressor). The issue as you mention is the venting. If you remove the center diverter. I think people call this a bow tie? It comes off with a screw or two you can get a much stronger flow of cold air.

As for the vents? I typically roll down a window.

Good luck,
Larry

[Neel]

The bow tie IS one of the first things to remove.. Griffiths makes a nice center vent that requires no drilling, it mounts under the ashtray, looks factory.. It doesn't increase air flow, it just puts the air where you can feel it..

[Todd Simpson]

As I understand it, there are significant differences in the dash sheet metal both for the outer face level vents and for the defroster of the newer style dash. (It might have been fenderguy that did the swap and posted some of the work in progress.)

I have somewhat related question-other than the vents, what are the differences between the '85 and '86 AC systems? Meaning, if I could replicate the better airflow of the '86, are there any *other* advantages to the later system?

[86 911 Targa]

Originally Posted by Joeaksa

I have a 85 model car and it has the tiny vents in the dash, with ever smaller vents on the outer side of the dash.

Was wondering the other day how much trouble it would be to mod the dash/car to the 1986 and newer vents that are a good 3-4 times the outlet size?

Anyone ever do this and if so how much trouble was it? Sure would be nice to have more airflow.

Thx,

joe

Joe,

If your A/C is of stock configuration, over and above the posted suggestions,
you may want to try the Rennaire High Flow Evaporator, and Pro Cooler.

Good luck,

Gerry

[tcar]

Joe,
Someone on here detailed what it took to replace the small (teeny) vents on each end of the dash with the big ones. Do a search... probably been a year and a half ago.

Said he would not do it again. Lot of work, cutting metal, etc.

The center vent to replace the bowtie is a great fix... but you can do it yourself for about a tenth the cost of the Griffiths. Buy the vent on Ebay for a few bucks and make a duct out of a piece of heater hose for a couple more bucks. Just takes a few minutes.

[MBAtarga]

Here's a thread with my solution to the center vent "upgrade."

Griffiths Center Kuehl Vent?

And as others have mentioned, there are a few threads referring to the large amount of work required to upgrade the dash to allow for the larger vents.

[Mitch Leland]

I bought a donor dash so I could have it recovered since mine was so badly warped. At that time I looked into buying a "86" dash so I could have the larger A/C vents, but gave up because of the amount of metal work needed to make it work. Maybe if I could have seen the two sub dashes side by side I could have gotten my arms around the project, but everyone said it wasn't worth it. I'm not a true purist, but I took solace in the fact that I left the dash stock.

With my upgrades A/C system I happy enough with the cold air, yes the distribution could be better...

[Oh Haha]

rptd

[mlfox]

Originally Posted by Joeaksa

I have a 85 model car and it has the tiny vents in the dash, with ever smaller vents on the outer side of the dash.

Was wondering the other day how much trouble it would be to mod the dash/car to the 1986 and newer vents that are a good 3-4 times the outlet size?

Anyone ever do this and if so how much trouble was it? Sure would be nice to have more airflow.

I found this photo somewhere on the web. This modification is one I'm going to try this season. I already have the center vent, and it made a big difference in the air flow. I have test fitted the vent below the headlight switch, and I don't think that there is a problem with knee interference.

Note that the owner of this vehicle had removed the "bow tie."

Regards,
mlfox

[Joeaksa]

Originally Posted by LWJ

Hello,
I have an 80. The vents are tiny as you mention. However, I have factory AC with the front and rear condenser. The AC works fantastic (even with the huge York compressor). The issue as you mention is the venting. If you remove the center diverter. I think people call this a bow tie? It comes off with a screw or two you can get a much stronger flow of cold air.

As for the vents? I typically roll down a window.

Good luck,
Larry

Larry,

Thanks but the bow tie has been removed for about 14 years now! Its an airflow issue for me, and if the vents are 1" x 4" on the ends you are going to get only so much air coming out of them, especially when the vents on the 86+ model cars 4-5 times the size.

Joe A

[javadog]

Even with the larger vents, you still want more air. The A/C in my '86 turbo is useless.

I think a better solution for airflow in an earlier car might be to find one of the under-dash units used on the early cars. Then, change out all the rest of the crap (compressor, evaporator, condensors, hoses, etc.)

Less work than modifying the dash sheet metal and I wouldn't be surprised if it worked better.

JR

[Joeaksa]

Originally Posted by 86 911 Targa

Joe,

If your A/C is of stock configuration, over and above the posted suggestions,
you may want to try the Rennaire High Flow Evaporator, and Pro Cooler.

Good luck,

Gerry

Gerry,

Right now thats easy! There is no A/C system on the car at this time, it was removed for my 3.6 conversion and 1973RS backdate. Only parts still on the car are the evap unit in the smugglers box and the vents/ducts behind the dash.

I do have a Performance Aire underbody condensor and their replacement "knee pad" vents, but have pretty much decided not to use them so am back to planning on how to do this best.

Right now am looking at using a 993 style condensor with fan in the front and rear left hand fenderwell. Will not use an actual 993 unit as after tracking one down and looking at using it was told by the A/C experts that condensor technology has improved light years since this was made so for $120 or so can get a lighter unit with a fan built in to put in both locations.

As well will not be using the rear engine cover mounted condensor. Do not want to add anymore weight in the back than possible. The A/C people I talked with said that one fender mounted unit should be fine, so am feeling that by putting one in the front and rear fender that this should do it here in Arizona in the summer.

Thx,

Joe A

[Joeaksa]

Originally Posted by mlfox

I found this photo somewhere on the web. This modification is one I'm going to try this season. I already have the center vent, and it made a big difference in the air flow. I have test fitted the vent below the headlight switch, and I don't think that there is a problem with knee interference.

Note that the owner of this vehicle had removed the "bow tie."

Regards,
mlfox

ML,

This looks interesting... Performance Aire has a mod where you drill a second outlet hole in the bulkhead and in this manner increase the airflow. Those vents in your photo may be hooked up to something like this.

Thx,

Joe

[Joeaksa]

Originally Posted by javadog

Even with the larger vents, you still want more air. The A/C in my '86 turbo is useless.

I think a better solution for airflow in an earlier car might be to find one of the under-dash units used on the early cars. Then, change out all the rest of the crap (compressor, evaporator, condensors, hoses, etc.)

Less work than modifying the dash sheet metal and I wouldn't be surprised if it worked better.

JR

Totally agree and more airflow is what's needed. Only way to make this happen is with a better fan and ducting that allows this to work.

Joe

[javadog]

Not only do you have small vents in the dash, have a look at the small hole that feeds air back to the evaporator.

JR

[carreraken]

Originally Posted by mlfox

I found this photo somewhere on the web. This modification is one I'm going to try this season. I already have the center vent, and it made a big difference in the air flow. I have test fitted the vent below the headlight switch, and I don't think that there is a problem with knee interference.

Note that the owner of this vehicle had removed the "bow tie."

Regards,
mlfox

I have this mod on my '85, and there is so little airflow in these side vents, it wasn't worth the trouble.

[BarryJB]

+1 on don't try to modify dashboard. Unless you do some mods to improve A/C thermal performance, I'd agree that further messing with the vents makes little difference, or is worth the cost/effort - given that removing the bow tie, and bending the resistor plate so it doesn't obstruct return orifice under the passenger floorboard, are zero-cost no-brainers that can't hurt.

BUT with some A/C performance mods, the under-dash vent mods aren't useless or a waste of resources; IMO they are great once the car is cool inside and you no longer need a direct cold blast in your face from the center vents to feel comfy. Not up to 21st century HVAC standards! But WAY better than the OEM performance with R12 or the basic R134a retrofit.

In 1997, it had stock R-12 system with Nippondenso compressor, under Carrera-tail and front-valance condensers - and poor performance with original R-12. 1998, converted to R-134a, included changing out front valance condenser for double-sized unit.

Later, put a footwell blower motor into the front condenser blower case (IIRC a direct or easy-to-mod swap, trickiest part changing over the impeller) - it runs at higher rpm; added a foam gasket around the top of the front condenser to help more blower air to be directed through it; obtained vents from RV supply and hose from my p-car parts museum to "replumb" new under dash-end vents (A/C air only just as mlfox's posted pics)... leaving the tiny dash-end vents hooked up to heat for side-window demisting, and replaced bow tie with a center vent over the cubby (all three vents less than $50 in parts); and added a trinary switch to the compressor, which should have been done with initial R134a retrofit.

After these mods, recharged or topped-up system and drove around monitoring center vent v. ambient temps with a dual inside/outside thermometer for a few weeks. Hindsight - have a pro shop determine and report the optimum charge ozs with the changed refrigerant and system capacity.

Result - dash upper center vent would show low 30's at low fan speed in 90 degree heat (SoCal) and still under 40 at high fan speed. Yes the center dash and bow tie do blow the most cold air and are initially the most comfort-causing; modded under-dash vents put out a bit - passenger vent more than driver side - but nonetheless, after 20 minutes on the road, it gets too cold for comfort and the vents can be turned away and the temp control can be set below max, which never occurred before the blower mods. If you don't park in the shade on a hot day, it takes over 20 minutes to cool the car to where one can reduce temp control, so on short trips with traffic and parking stops (shopping runs) min temp and max fan direct blast is still required to get relief, but that direct blast is good and cold enough after a couple of minutes that I didn't scrap the whole system in disgust, as was imminent before mods.

Just increasing cabin (evap) blower output doesn't decrease the vent temp, it increases it. Lack of condenser efficiency seems to be the biggest issue especially after changing to R134a. I believe increasing the front condenser size was what allowed the R134a retrofit to match the original R12 set up - but it was increasing the front condenser blower output that let it work acceptably and get vent temps down to 30-something for any fan speed in 90 ambient. Then that improvement spurred me on to make the vent mods - which would then better exploit an upgraded cabin blower... and so on

[Reuben911]

Hi Barry

Sorry I know this is an old thread

Quote "(all three vents less than $50 in parts); "

Where did you purchase the vents from.