Brake ducts in R-package front lip
 

Has anyone ever tried and had success with molding brake ducts into an r-package front lip?

I'm thinking of trying to use ducts like these: https://www.pegasusautoracing.com/pr...p?Product=3624

And molding them in to the r-package lip such that they're kind of like this (the brake ducts would be on the backside of the lip).

Of course, some modification to the r-package lip would be required.

I've considered something similar but with a GV replica lip.

The question is will you be able to flow enough CFM through that opening. Most brake ducts use a 2.5" outlet so choking it with a 1" inlet would be a waste IMO. See if you can find a similar inlet with a cross sectional area closer to the equivalent of a 2.5" diameter.

Is that all the bigger the front lip opening is? I just ordered one yesterday and from the pictures I figured the openings were at least a couple of inches tall.

Dang. I may need to rethink this.

Here is a couple that have 2.5" outlets. but are probably too tall to fit nicely in a r package lip

https://www.merlinmotorsport.co.uk/s...r-intake-ducts

the 1 in outlet will help cool your brakes some. It just would choke at the inlet and would not work nearly as good as a larger opening.

2.5 in diameter = 4.9 in^2
1 in diameter = 0.78 in^2

That's an 84% smaller opening.

I don't think your adapter thing is necessary...

I used a 3" sceet hose on my r-style lip and bent the opening of the tube into roughly the shape of the back/exit side of the holes in the lip and tape/zip-tied it all together.

It works well- tested up to 125mph. :)

I'm definitely going to go with the 2.5in duct. It's just a matter of how much I have to hack up the bumper and front lip to accommodate it. I used a similar setup on my E30 and it was nice not having to ever worry about brake fade.

I guess another option is to just cut out openings in the bumper but it seems like this could be such a clean install that I don't want to abandon it yet.

Hornetball has done it. Go through his NA car build thread and you'll see a fairy detailed how to.

subscribed. I plan on making some for my GV style lip this spring using carbon fiber sleeves which can expand to form the correct shape in a smooth profile. I know that area of the bumper isn't the best for flow, but its better than nothing for a light duty HPDE car.

I've always said that the Track Dog 'splitters' (just ABS plastic lip) were useless, but actually if one were trying to pull air into the stock R-package lip openings for brake ducting, one of those little ABS extensions would actually help to build up some pressure at the duct opening.

-Ryan

Or you could put the hoses in the corners of the mouth, as God intended. :party:

I've been thinking of doing this myself. My plans were to 3D print a little converter that would sit over the intakes on the 'R' package lip. The oval intakes would need to be trimmed back to a certain point with the 3D print rivetted over the top them to the tabs either side.

I need to check the size of the intakes but I think they are just large enough to be converted to a 2.5" round hose.

I'll have a look at it again tonight and see if I can get something that might work.

oh man. why are you guys over-engineering this?

1. bend hose opening into an oval.
2. attach hose to holes that ALREADY EXIST on your lip (I hear duct-tape works well on ducts).
3. enjoy cooler brakes

+1, simple and effective.

Why did you make me drill holes into my bumper cover? It was so innocent before it met you. :qq:

+1 i did this, happy with results, A++ would cool brakes to the max again

Post up the cad files if you do. I have 3d printing capabilities.

Mine are routed to the R package lip. Just the hoses with some nice gorilla tape sealing them up. As people have said, don't overthink it. Sure you won't get 100% perfect airflow, but it definitely won't hurt

Just to give a link:

https://www.miataturbo.net/build-thr...8/#post1130011

Even though I used the R package lip ducts and it seems to work OK on my normally aspirated track car, I agree with Andrew. If you're going for max airflow, 2.5" hose routed into the radiator inlet gives a more direct, larger path that will flow more air.

With the wheels turned, the R package lip ducts are inline with the tires. That means that the path for the flexible hose has to go inboard to the frame rail/undertray side before turning back outboard to the hub. Not ideal. And, as others have noted, the R package lip ducts are smallish.

Thing is, it gives me a reason to make something on the 3D printer which I enjoy. When I get the time I'll model up a little adapter that will sit over the lip and transition it into a 2.5" and / or 3" round. 3D modelling will only take 15 mins, its getting the tolerances and figuring out the angles that takes more time.

I'm just finishing up a printing a complete rear wing with a custom profile. It's been using up my printer time as I've had to print 12 sections, each one around 12 hours or so. Once I've finished that project I'm going to look at printing a custom airbox or maybe do the brakes ducting first.

I realise I could mount it all up with gaffa tape, but if I applied that theory across the whole car I'd end up with something hacky. I find it enjoyable to build nice custom parts...

Post up pics when you get around to doing this

A wise man once told me: When all you have is a hammer, every problem looks like a nail.

...Doesn't mean the hammer is the right tool for every problem ;)

-Ryan

But if you have a hammer, it's fun to bang it!

If I had a 3D printer at my disposal, I'd have all kinds of fun with it.

I fully support just banging for the hell of it.

-Ryan

x2 Then need to hurry up and get "affordable"

A motto I could get along with. The wife might not agree.

You can get a decent one for under $500 these days. What's affordable to you?

I didn't realize that... I was still seeing 1k+ numbers. What model do you have, out of curiosity?

I'm using a makerfarm prusa i3 8"

Prusa 8" i3v Kit (V-Slot Extrusion)

The flashforge ones look like to be a good bang for the buck printer tho.

Prices should still continue to drop for the next year as I've been seeing a lot of china companies developing and selling printers direct from manufacturer rather then via a US reseller who would mark it up.

I'm going to give it a year, and buy the second generation of the first <400$ printer I can find. First generation always blows.

Many companies are already on their 3rd plus generation machines. Most of the major kinks are worked out. The g-code generating software is constantly being improved so it's always neat seeing what new features they have.

At work we use a stratsys which runs about $30k. I'm sad that it set the bar way to high for my 3D printing expectation and no hobby entry level machine can match it. It just works. period. No tinkering with and adjusting a bunch of settings. Perfect prints every time. But still for the price, it's pretty impressive what the budget ones can do and how far the tech has come since then.

What I'd love is a budget system with a temperature controlled chamber rather than just the heat bed. I always have print warping issues on larger prints due to the temperature difference between the lower and upper layers causing contraction stresses. The Stratasys machines control the temperature of the entire chamber so there is no stresses in the part while printing creating very reliable large prints.

We also have a stratysis at work. Also an UP! The up has the heated cabinet. Also my friend just got a printer with a heated cabinet but I can't find the name of it, it was just barely sub 500 but he prepaid and waited 5 months to get it.

It looks like the Up printer is just a heatbed type printer with a shielding enclosure to reduce air draft but not a true temper controlled heated chamber. The Stratasys ones use no heat bed and instead have the entire print in an oven. The shielding should help some with that issue but I doubt it would solve my issue of large print curling on ABS.

if you friend bought one with a temp controlled chamber rather than heat bed please let me know the details of it if you ever find out. :party:

Solid doodle press. Heat controlled bed. Stratysis has a patent on the temp controlled chamber.

ahh, that makes sense... Damn maybe ill rig up a heat gun or air dryer to blow hot air at my prints. :facepalm:

12v fan, heating element, microcontroller, temp sensor.

Damnit, now you got me looking at DIY heat chamber projects. Looks like another project to add to my list of shit to do.

PS: sorry for the thread de-rail. 3D printing some GV brake ducts is on my to do list so it's only slightly off topic I guess.

Our stratysis is pretty awesome, we have done a bunch of hacks to it, so we have refillable cartridges (saves us $100's), we added a raft of support material to the bottom of the print so that we can reuse the beds, about quadrupled the print resolution and were able to change some of the settings for multicolored printing.

I used my lip duct for a CAI, because streetcar. when heat soaked, AITs drop like a brick at speeds even under 10mph.

Has anyone thought to take a page out of Porsche's GT3 playbook? Their brake ducts are moulded plastic pieces that attach to the control arms and very effectively direct air to the rotor:

https://www.miataturbo.net/attachmen...ine=1424541239
https://www.miataturbo.net/attachmen...ine=1424541239

Here is the setup from the current GT3:

http://www.elephantracing.com/tool-b...karound-11.jpg
http://www.elephantracing.com/tool-b...karound-12.jpg

Thats neat. Usually you want air being forced into the center of the top hat rather than the surface of the rotor but that would help too.

making a tool specificly for the miata for plastic injection or vacuum molded parts like that is more of an OEM undertaking where you have exact CAD dimensions of everything and can spread the tooling cost over a number of cars. Someone with really good fiberglass and layup experience can probably come up with something tho.

Only marginally effective. It's a 'better than nothing' approach. So much pressure loss before it gets to the rotor. The current C7 stingray corvette has the same thing, we're removing it all and replacing with proper brake ducts for a customer who can't get his brake temps under control with those.

-Ryan

here is a link to a 3D model I made of the converter part. I haven't taken final measurements and angles yet as the duct needs trimming on my car.

https://lastpixel.app.box.com/repres...9kik0gccv6djnk

Took me longer to figure out how to post the image than to model the thing. This should print pretty easily in one piece. Probably a 4 hour print.

No link. ??

Fixed... gotta find an easier way to link to photos!

Are those for r package or GV lip and any pics of it installed or test fitment

Link to the files?

That's cool. Prop+

Yeah I don't see it either.... not sure if Monk is just trolling us, or is just really really really smart. :party:

That's really awesome. I would love a pair.

Nice, i can see the pic on my phone. Maybe it was just my work PC.

Not sure why I said "link to the 3D Model" in my post, I meant link to the 3D renders. Anyway this part needs some test fitting first so I'll do all that on my car, make sure it fits then I'll give everyone a link to the final 3D model.

My car is a 1989 Eunos Roadster which I think is the 'R package' lip. I'm not sure if there were changes or not in later models. I can make a CAD cross section to test fitment anyway.

I have the GV lip, if you post up the CAD files I can try and modify it to fit the GV lip.

Are you designing them to have a 3'' outlet or 2.5''?

I can easily scale the end connection to whatever OD is required. I think mine is actually a 3" duct but I might drop it to 2.5" for the final one as I don't need massive cooling.

I'm actually printing it a test piece now... should be done in a few hours.

aidandj, if you can send me a photo square on to the back of the duct with a tape measure held up in line with the edge, I can quickly model a version that should fit. I'll actually also need a bottom up shot as well that is square to the body so I can see the angle it comes off the bumper. Maybe give me overall height and width measurements too, preferably in mm!

Bitch and a half to get a good picture. Heres an album with a bunch of pictures and an attempt at a dimension. The inlets are kind of a weird shape.

http://imgur.com/a/9ZJSB

That will do. It would be easier if you jacked up the front a bit higher! There is one good profile pic I can use, but the entrance flares a bit so might be a bit tricky to get it right from photos alone. It looks like it comes out of the bumper in the right direction so it would be a matter of just converting to the circular output.

What size output do you want? 2.5 or 3"?

If its not too much then one of each. Still not sure what I am going to run, and I know some of the local guys might want a set of them.

both will be easy enough... The hard part will be getting it to sit over the radius flare nicely. Have you got access to a printer? I'll just have to guess model it, send you the 3D and you can feed back where it hits, maybe even tweak the 3D file at your end if you have a 3D package.

Yeah, I have a printer at work and solidworks. I play around with it some but I'm mostly an EE guy. I can print as much as I want though.

Modelled quickly over lunch. Pretty hard to see where it has to clear the bumper mount point.

here is what I got: https://lastpixel.app.box.com/repres...qrjcytnmpnmu1k

Here is a download for the 3D Model (in 3ds format) GV_Brake_Duct_3inch.3ds

When printing it, you may need to add some supports to where the cutout are on the model.