MKIV roadster Air conditioning?

[rtbellah]

Ordered my kit...expected in July sometime...can't wait! I'm trying to line up a few things before it arrives so I started looking at AC/heat optiions. I am
having trouble trying to figure out what the best way to go for AC in my roadster is - North Racecars, Vintage Air, or ????. Anyone with recommendations/advice please respond - I live in AZ so AC is a MUST but it's all a little confusing.

[Hacksaw84]

Posting the engine will help with responses.

[frd2]

I have the North Race Car version - it works well (not oem / freeze you out well......) I think it has an issue fitting up with a gen 3 coyote. Otherwise any system you use will not care about engine choice as long as no interference physically with the exception of the appropriate compressor.

Having a top is far more valuable than having AC. without the top the AC is for bragging rights. With a top (and no humidity) then the AC is a nice addition but not required imho. Different answer where there is humidity.

[rtbellah]

Don't hate me - but my engine choice is the 427 LS motor from Blueprint. I decided that for the money it was hard to beat the performance and reliability. I am getting the soft top as well. I am mostly concerned with the space for the evap unit. I have looked at the North Race Car unit and it looks like the best fit....even if it will be tight. My plan was to wait until I get the kit so I can take my own measurements and check fitment.

[rtbellah]

Thanks for the input frd2! I was leaning that way but will wait until the kit arrives so I can get more accurate measurements and fitment ideas. I plan to drive my MKIV almost daily so AC will definitely be required here in AZ.

[GoDadGo]

Henry Renaud (65 Cobra Dude) knows how to do the HVAC thing rather well.
He's a professional builder & all-around Super Cool Dude located in South Florida.
This was one of his builds that had everything stuffed into a very tiny package.

https://youtu.be/sUAnYcvbxyE

[lewma]

Don't hate me - but my engine choice is the 427 LS motor from Blueprint

Im putting that same engine in my Gen3 Coupe build :)

[wallace18]

I have done the A/C with a Blueprint 427. See this build thread.

https://thefactoryfiveforum.com/showthread.php?21008-Bill-amp-Laura-s-MK4-build-thread

[Alan_C]

I have ridden in a MK4 with AC in AZ, Prescott so a bit cooler than the valley. IMO, it was not very effective as a lot of the cool air never hits where you need it most. With an open cockpit, really tough to get the kind of AC performance you are used to. Hopefully you can find others who have optimized their systems.

[bobl]

I'm not sure the Vintage Air system is even available. I used the North Racecars system. I do not have a top but it still has some benefits. First is sitting still in traffic. It helps quite a bit. Secondly I put vents in the corners that aim at the foot boxes. It makes a big difference in keeping them cool or warm. For the cost of buying a heater the AC was not a whole lot more. I've installed both the Vintage Air and NRC systems. The NRC is more compact. Either way there is not much room behind the dash.

[ProJoe]

I'm in the Phoenix area and just went through piecing together an AC setup for the LS3 in my Gen 3 coupe.

I ordered the DIY-style kit from Factory Five. it comes with the condenser, evaporator/blower, heater control valve, ducting, vent ports, all controls/wiring, and a make your own line kit (Vintage Air made). Per Vintage Air for the compressor I used a Vintage Air 04079 (https://www.summitracing.com/parts/vta-04709-vma) compressor with the Vintage Air low mount LS (https://www.summitracing.com/parts/vta-141810) bracket.

I haven't made it to the point of testing it yet but everything fit well and appears it will work without issue. Let me know if you have questions! doing a LS can be a little but of uncharted territory sometimes (at least in the coupe world).

[j.miller]

North Race Cars is a prime product. That being said it's a roadster (no roof) (big hole above your head). If you plumb it up a pantleg or run it into a cool suit ......ok, I'm going to whisper this, POINT IT DIRECTLY AT YOUR CROTCH it will help. With the angle of the windshield, black seat belts and the sun overhead all the heat is concentrated on your,,,,well,,,, you know,,,,,YOUR STUFF ! It's not by design but it is how it works out. I found to never drive over 90* . 85* 30 -45 min. 80* all day long. When traffic stops take any degree and add 15*. Drink water (lots of it) over 80*. The temp and wind will suck the moisture out of your body faster then you can replace it. I got caught in a 102* stand-still on a freeway and am lucky people could see I was in extream distress (I didn't understand I was losing it) and they helped me to safety....jus sayin...da Bat

[rtbellah]

Thanks J.Miller...I needed a good laugh today - almost fell outta my chair reading your post! I am getting the soft top so I'm hoping with the top on I will be able to survive some Arizona summer driving. I won't be going out on those 120* days but 100-110 I should be able to survive....maybe I should install a camel pack in the trunk and feed a tube to the drivers seat! :p I am leaning heavily toward the NRC system due to the size but I won't pull the trigger until I have my kit in hand - I'll keep looking in the meantime for other options.

[John4337]

I have Richard’s system (North Racecars) it works as well as can be expected in a car like this with lots of heat intrusion. It doesn’t do much with the top off other than a bit of relief at lights. Where is really shines for us is with the top on in the rain. We’ve gotten caught a lot and it really works. If you go for it, add in the defroster plenum. Only uses one of the A/C outlets and keeps the windshield clear.

[rtbellah]

Thanks for the input John4337. I am currently leaning toward the NRC setup. So if I have the top on in AZ heat (110*) and I have sufficiently insulated my firewall and cockpit do you think this unit will keep the interior comfortable? It doesn't have to freeze me out - just keep it reasonable. Would appreciate your thoughts since you already have/use the system. I will add the defroster as well - even in AZ we need it occasionally and it would really be a pain to add after the build so I will include it up front.

[Desert Cobra]

[I live in Tucson so I know about heat. The answer to your question is very simple: You will not feel any cooler in a roadster with AC than you do without it. Don't believe me, then ride in some ones roadster that has AC and you will see. As to heating, again what is the point? Its your ears and face that get cold not your feet. Vent ducts to the foot wells works great for me and the wife. One friend with a heater says he can hear a fan blowing somewhere under the dash, but can't feel a thing. The simple fact is there is no way any AC can stay up with 100 degree plus temperatures in a roadster.145545

[timwert65]

These work extremely well. You would need to remove your seat cover and either have a new one made that is perforated, or have the existing perforated. I have used something similar to this and it is amazing how much air they move.

https://katzkin.com/degreez/

They do have an installation shop in Phoenix

[John4337]

Chasing heat leaks is the key, even a small hole will feel like a blow torch, at least is did in S. Florida when I lived there. Also blocking heat from the engine bay. All of my experience has been in a humid environment, so may not apply to your desert heat conditions, but with the top on and the side curtains in, its does help. Mine struggles a bit at lights/stops, I guess lack of air moving over the condenser. I would certainly do it again without question. If anything, I’d have spent more time insulating the cabin from heat. I still have a small leak around one of the wiring pass thrus that I’m trying to plug.

[TMartinLVNV]

[I live in Tucson so I know about heat. The answer to your question is very simple: You will not feel any cooler in a roadster with AC than you do without it. Don't believe me, then ride in some ones roadster that has AC and you will see. As to heating, again what is the point? Its your ears and face that get cold not your feet. Vent ducts to the foot wells works great for me and the wife. One friend with a heater says he can hear a fan blowing somewhere under the dash, but can't feel a thing. The simple fact is there is no way any AC can stay up with 100 degree plus temperatures in a roadster.145545

I live in Las Vegas so I also know about heat. I think that the answer to rtbellah question is that it is his car and he can do what he wants with it. Maybe he wants it to extend his comfortable driving season? Maybe he wants it for bragging rights? Maybe he is not concerned with driving in 100 degree plus temperatures?

I have a heater in my car. I'm not relying on what a friend tells me. I find the heater to be very important to long trips. I've been on a 1000 mile trip in three days. I've been on many more shorter 2 and 3 days trips. I've put 6300 miles on my car in 9 months. The heater was fantastic when starting the car on a 20 degree morning at 10,000 ft altitude and driving down a mountain. The heater is fantastic when I should have brought a jacket and didn't. I've never heard my heater fan when driving. The pipes are too loud. I sure enjoy the heat coming out of the vents that I have pointed directly onto my hands while on the steering wheel. It is so nice, I don't even bother with gloves when driving in near freezing weather. I hardly use my seat heaters except for when warming them up. Then I turn them off. My ears and face have not been a problem either. I have a hat on and a balaclava. Even at 70 mph, I can unzip my jacket some, open it up, and catch the nice warm heat coming out of the vent after warming my ungloved hands, and warm up my torso.

I guess, that is the point.

[Alan_C]

In post 13 the OP notes that he is going to have the soft top. The top will help tremendously to hold the cool air in and make best use of the AC.

For those with a open top car, the use of one of these cooling towels for the neck could be a far cheaper and simpler solution.

https://www.amazon.com/RiptGear-Cooling-Towel-Instant-Workout/dp/B07FJL9MGR/ref=sr_1_11?m=AHO6MIKBDVQB7&s=merchant-items&ie=UTF8&qid=1534760732&sr=1-11&tag=coolingtowelg-20

[Randy's]

I configured my own system using Vintage Air components. I had NAPA cut and crimp the hoses. I used the firewall forward kit and had to remove the middle support bar on the dashboard loop. Using Vintage Air's mock-up unit, I made a template to do the cut-out in the firewall. The unit "straddles" the firewall, 1/2 inside and 1/2 outside (in the engine bay). I created the air box cover using extra aluminum and sealed everything with 3M strip caulking. I am very pleased with the outcome and how effective it cools. I am in the Atlanta area so I know hot. The key is having vents that direct cold air into the footwells, they are on the sides of the under dash console, in addition to vents in the dash.

[ydousurf]

Great thread! Thanks for the post-n-pics, Randy! I'm planning going with VA for my unit as well. And you answered my question regarding making it work with the wiper motor! I am curious though, is that the Gen II Compact or Gen II Mini? And it looks like you had to remove the vertical brace on the dash hoop as well? Any other pointers or down-fall dilemma's you can share, please do! Much appreciated!

Dj

[CaptB]

Don't hate me - but my engine choice is the 427 LS motor from Blueprint. I decided that for the money it was hard to beat the performance and reliability. I am getting the soft top as well. I am mostly concerned with the space for the evap unit. I have looked at the North Race Car unit and it looks like the best fit....even if it will be tight. My plan was to wait until I get the kit so I can take my own measurements and check fitment.

Why would we hate you? I'm jealous! I'm waiting on my lower cost 347 that should be here this month.

[rtbellah]

Thanks for the post/pics Randy! I had the same vision for the under dash center console/tranny tunnel....yours looks great! Until I saw your pics I didn't know if the gen2 mini would fit -now I know! I would like to go with VA because of their track record but thought that option was out of the question due to size....even though it is tight I think your install is very clean and efficient. If you don't mind could you post the parts list for what you ordered from VA...want to price out and compare with the NRC option.

[Randy's]

Thanks for the compliments. I will pull the invoice from my files and post it. It has everything I ordered, other than hoses, listed on it. I purchased everything from Summit Racing. I'm not sure which is smaller, Compact or Mini, but I purchased the smaller of the two. Because I was unsure that this would work, I did order the Vintage Air mock-up unit first. It is simply the main unit plastic housing, no internals. Using that mock up unit, I concluded that I could make it work. I also cut it in half to determine where to cut the hole in my firewall. In addition, I purchased the firewall forward kit. I don't think you could do this with the regular Factory Five firewall. Yes, I did have to remove the vertical brace on the dash hoop. The unit in the dash had to be installed with a "tilt" to get it to fit but I have had no issues. I also purchased the unit with defrost. They make one without. The blower motor on the unit has a plastic cover around it. I had to remove that and mock up an aluminum "box". This box was also lined internally with X mat material to insulate it. This was needed because the unit sits half way in the passenger compartment and half way in the engine compartment. The only other thing worth mentioning is that the unit practically "sits" on the square tube that the firewall installs to. Because of that, and because the unit has vents on the bottom, I did not try to attach and route any hoses to direct the air coming from those. I only attached hose to the vents coming out of the top of the unit and used a splitter to route hoses/air to the footwells and the dash. It is indeed a tight fit, but it works. The Vintage Air unit is quite robust and pumps out a lot of cold air.

[Lancaster Lad]

Randy's
Thank you for the extended details on your install. I was going to ask about the floor/heat vents.
Since I have the dummy unit I could not figure out how to use the floor outlets. Your solution to just ignore
them seems to work. I guess if they are left open and used bi level for heat some extra hot air will reach the feet.

[BluePrintEngines]

you wouldn't be the first LS we've sold to MKIV customers, or the first MKIV we have sold A/C for :)

just remember, the engine will come with the A/C compressor on it. Don't let the A/C unit supplier talk you into a compressor.... you'll then have 2 compressors, and the one you got elsewhere may not even have the right ribs, or pulley, or attachment points, etc. Just saving you the hassle down the road!

Here are all the LS packages.
https://factoryfiveengines.com/blueprint-engines-factory-five-engines/ls-complete-packages/gm-427-ls
https://factoryfiveengines.com/blueprint-engines-factory-five-engines/ls-complete-packages/6-2l-ls376

full offering sheet
https://factoryfiveengines.com/blueprint-engines-factory-five-engines/blueprint-engines-factory-five-complete-pricing-list

any questions, give us a call!

[phileas_fogg]

Randy's
Thank you for the extended details on your install. I was going to ask about the floor/heat vents.
Since I have the dummy unit I could not figure out how to use the floor outlets. Your solution to just ignore
them seems to work. I guess if they are left open and used bi level for heat some extra hot air will reach the feet.

If you're not going to use the vents, I recommend you plug them. On my heater unit, the water in the coil always gets hot despite the shutoff valve. I found that on hot days, I always had hot air blowing out of the heater vents. It's sooooo much easier to plug the vents with the unit out of the car than it is to crawl up under the dash & try to fit the plugs in after. I expect that when you want cold air, you're going to want every bit going to your vent rather than cool the back of the gauges.


John

[Lancaster Lad]

Mr Fogg
Thank you for the suggestion. I forgot about heat creep. I may still plug the bottom and 3D print some adapter to reroute
the ductwork, don't know yet still about 1 year until I have to make a decision.
now back to our regularly scheduled program.

[Scowally]

I have found the following steps allows for proper A/C cooling:

1. Roll down the window for airflow - where is the goddamn hand cranky for the window? Nuts!! There isn’t a window...
2. Put the top up to get out of the heat... What, there’s no top! I’m having heat stroke here!! ...said like Dustin Hoffman crossing the street...
3. Bake in your own juices as the heat piles drives you into your seat...
4. Pull over and find an overpass... or tree... or whatever to get some shade for a few minutes and contemplate taking your own life...
5. Get back into your car... Start her up... and start grinning like an SOB as you realize that most people will never understand the draw of an open top roadster...
6. Let her rip as you gun it getting back into traffic for your insufferable - I meant, enjoyable, ride home (Sorry, Freudian slip...)
7. And finally... Yell at the next car hogging the fast lane, probably a Prius, to... “get out of the fast lane you moron!

[rich grsc]

I have found the following steps allows for proper A/C cooling:

1. Roll down the window for airflow - where is the goddamn hand cranky for the window? Nuts!! There isn’t a window...
2. Put the top up to get out of the heat... What, there’s no top! I’m having heat stroke here!! ...said like Dustin Hoffman crossing the street...
3. Bake in your own juices as the heat piles drives you into your seat...
4. Pull over and find an overpass... or tree... or whatever to get some shade for a few minutes and contemplate taking your own life...
5. Get back into your car... Start her up... and start grinning like an SOB as you realize that most people will never understand the draw of an open top roadster...
6. Let her rip as you gun it getting back into traffic for your insufferable - I meant, enjoyable, ride home (Sorry, Freudian slip...)
7. And finally... Yell at the next car hogging the fast lane, probably a Prius, to... “get out of the fast lane you moron!
It's like you read my mind