Nb dash gutting
 

Tried to search, but my google fu is weak.

when putting the dash back in my challenge car today, i realized just how heavy it is. Wow.

this will be a hpde/autocross/challenge car. So, need to keep heater and gauges. Mirror switch. Id also like to keep the dash stock appearing from a visual standpoint. Will still be using all factory mounts to the car, as well as the steering column mounts.

what all have you guys done to lighten these? Im planning on the air bag delete, but that should only get about 5 lbs is my guess.

throw out what/how/how much you did, and rough estimate of the results.

thanks guys.
Michael

I'm about to undergo the same task, air bags are actually way more than that but can't remember how much, might check the weight loss thread. I'll also be pulling the a/c condenser but I'm more interested in what structural things that can be trimmed to remove weight.

I gutted most of the dash in my NB. I gutted the HVAC vents but kept the defroster and floor fans. All of the eyeball vents have been gutted. I cut as much of the dash support off as I could, but I kept the bar and trans tunnel supports in place for safety reasons. I also moved my ECU to the passenger side airbag location with a harness extension. I gutted most of the un-necessary wiring out of the interior harness.

No idea how much weight it saved, but it did make my dash more simple and easier to remove.

The passenger airbag is ~1/3 of the dash weight. To keep it stock appearing and keep HVAC, you will be doing just an airbag delete.

really? its that heavy???

and I'm sure theres other places to lose a pound or two. like gutting the glovebox and reattaching the outer skin.
and no AC. just heat.

Yes, it is. What are you going to gut from the glovebox? It is entirely plastic and weighs nearly nothing. The AC is not in the dash, it is attached to the firewall.

The dash houses: the dash support bar (needed to attach the actual plastic dash to the car), the ducting for HVAC (all plastic and light), wiring (need), airbag, and the actual plastic dash which is an overlay over the support bar. The airbag cover, which is plastic can be removed and reattached to the dash. The AC box is attached to the firewall and can be removed and replaced with a piece of ducting from Mazda, but I assumed you already did that.

Ounces make pounds.

haven't gutted the evaporator yet, as im still in rogh fab and mockup phase. Hell, im not even finished seam welding yet, or got all the cage tubes bent. But im trying to learn and plan, and do the best i can as i go.

Airbag was heavy as fork. I was honestly very surprised just how heavy.

The passenger airbag in my NA was 10.3lbs. NB is probably similar.

You could do an NA6 dash swap. Andy Hollis managed to make an NA6 dash fit his K24 NB.

Some reference weights:
My NA6 dash was 25.75lb before cutting.
The Evaporator was 6.5lb

Again, this is all on my 95 but the the hvac weights ought to be similar on the NB.
https://cimg4.ibsrv.net/gimg/www.mia...f582167909.png

The NA6 dash into the NB is pretty common among nationally prepared CSP cars. Most swap over to NA6/8 door panels as well.

This is so you can legally remove the passenger airbag.

As this is a grm challenge car first and foremost, an na6 dash swap is probably not feasible.

additionally, car will probably wind up in xp due to the turbo v6. So we can get pretty radical.

the graph you posted: what are the numbers? Ive been trying to make sense of it, but with no success.

Spreadsheet appears to show weights in grams and lbs.

Ah! Thank you!

This has mostly been covered, but I'll throw in a pic for posterity. The ducting that is attached to the dash is very light plastic, and you wouldn't gain much from removing it. The stereo and airbags will be much more significant. The blower motor, AC and heater elements are all attached to the firewall, and while there's a considerable amount of weight there, you're stuck with it if you want to retain any of the HVAC.

NB dash, and HVAC ducting:

https://farm5.staticflickr.com/4598/...e7e89546_c.jpg

On my NA track car, I removed all the HVAC parts and will be using a boat blower motor for defrost duty, if I ever get around to installing it.


https://cimg0.ibsrv.net/gimg/www.mia...69c6d522a0.jpg

Looking at your picture, and not my particular dash, what are the thoughts about drilling all the support structure except the tube? Seems like theres quite a bit of weught there.

also, how are you planning to heat/attach the blower to the defrost vents? Defrost is my main concern causing me to want to retain the hvac stuff. If i can delete it all cheap enough, i happily will.

I guess it all depends on how much effort you're willing to expend to remove a couple of pounds? Go for it, and add the results into the weight reduction thread... for science! ;)

I retained all the molded plastic venting when I gutted the NA dash, and will probably just use dryer hose off the fan into the original defrost vents. They are very light. I'm still considering an electric heater element, but haven't found a really suitable one yet.

BimmerWorld Front Windshield Defroster Kit

I do think ditching the heatercore isn't quite as straight forward as you would think. you have to do some serious consideration of the mixing manifold setup. I believe that info is in teh cooling system thread.

Remove and loop has been working fine for me.

If you get creative you can end up with....

https://farm5.staticflickr.com/4487/...a7ceb286_b.jpg
20171024_182448 by concealer404, on Flickr

Its in the process of getting a big gm v6 stuffed in it, so the miata engine specific coolant stuff doesn't really apply. Going to be interesting to see how cool i can keep it though.