Functional Aero Parts and their effects ?

[glamcem]

Originally Posted by Reaper

im surprised there aren't more homemade splitters popping up. Some of these companies charge a premium for flat stock. The ft86sf one is at least a good price and is water jet cut, so its at least made out of something relatively hard. Im about to just buy a big flat chunk of ABS and cut it up with a jig saw after seeing some of the prices on something im going to smash the hell out of.

if you take a look at the original post you will see that I was initially planning to do the same but keep in mind, my friend who followed that route ended up spending about $100 on materials and another $100 or so for someone professional cut and align the part for him and I am pretty sure he would jump on a splitter like this if it was avaliable for his Miata (unluckily Miata aftermarket support is very limited), I think it looks fine but the material looks a lot stronger on Hancha/FT86SF's splitter (compared to ABS plastic)..and they did a great job providing the good thought product, necessary parts, installation instructions and good packaging.. if you consider all that I think it's well worth the $300..

you can still try to cut it that ABS plastic and align by removing bumper but at that point you will be spending good amount of time and possibility to ruin the part you purchase, if you're really experienced with that kind of stuff though and don't mind spending hours working on it I'd say go for it . I also like to save some money on basic stuff, in my opinion $650 is ridiculous for a brake ducting kit and insert so I wanted to make my own, see my Custom Brake ducting mod in DIY section (in my signature) and in order to figure out a good method I had to destroy a 12 ft ducting hose (costs about $70) .. I'm still happy that I didn't spend the $650 on that so it all comes down to cost and effort



for the rest , I think @FT-86 SpeedFactory @plucas @eric6 can better answer your questions.. I am waiting on the new race version upgrade with supporting rods and hopefully I can try the newer version on the upcoming track events, I have couple events scheduled this week and will report back

[eric6]

Alright, first time stumbling across this thread and I figure I will take a stab at the questions presented.

Material: It is a plastic. I personally spent 50+ hours researching affordable materials that is aesthetically appealing, cheap enough for the masses, and rigid enough to handle the downforce created by the splitter. It is not proprietary, but seeing how we put in the R&D and effort to figure out the material we use, we decided to keep it to ourselves for the time being. Contrary to what most people think, R&D takes a lot of time, effort, and money. We still haven't covered our costs for the prototypes we built out of aluminum, ABS, and this material... not factoring in the engineering time. I apologize if this upsets anyone but the information is out there... if I found it, you can too.

Here's a shocker... both Paul and I do not like using this material. Their are better materials out their and we want to use them. But the price point would make it un-achievable for 99% of you guys, so what is the point?

Design: The design isn't complex but neither is the fundamentals of how a splitter works. That's the cool part about splitters, they all function if you follow a few certain rules. What we did do though, is offer CFD analysis which allows the end user to comprehend the additional grip offered at speed. It also allows the customer to better setup an entire car's aerodynamic balance for racing. Without this data, you can only guess at what other products out there do.

Rigidity: Neither the splitter nor the bumper are the most rigid pieces out there. The splitter does fairly well by itself, but the bumper is all plastic and bows with much load added. That is why we are producing and coming out with a race splitter kit. This upgrade kit will add 34% more downforce with a minimal drag increase, and include a splitter tie rod kit that adds support directly to the crash beam. If you add a splitter tie to anywhere that isn't metal (APR's goes to the plastic bumper in all the photos I have looked at), the splitter tie is in no way holding much load, if any.

Leading Edge Design: The whole trick with these splitters was to produce something that was affordable to the masses. While a contoured leading edge would be beneficial, we did not have the ability to do this cheaply. That sharp edge is great for cutting people's ankles as well !

I think I answered most of the questions.

Thanks,
Eric

[ddeflyer]

Originally Posted by eric6

Alright, first time stumbling across this thread and I figure I will take a stab at the questions presented.

Material: It is a plastic. I personally spent 50+ hours researching affordable materials that is aesthetically appealing, cheap enough for the masses, and rigid enough to handle the downforce created by the splitter. It is not proprietary, but seeing how we put in the R&D and effort to figure out the material we use, we decided to keep it to ourselves for the time being. Contrary to what most people think, R&D takes a lot of time, effort, and money. We still haven't covered our costs for the prototypes we built out of aluminum, ABS, and this material... not factoring in the engineering time. I apologize if this upsets anyone but the information is out there... if I found it, you can too.

Here's a shocker... both Paul and I do not like using this material. Their are better materials out their and we want to use them. But the price point would make it un-achievable for 99% of you guys, so what is the point?

Design: The design isn't complex but neither is the fundamentals of how a splitter works. That's the cool part about splitters, they all function if you follow a few certain rules. What we did do though, is offer CFD analysis which allows the end user to comprehend the additional grip offered at speed. It also allows the customer to better setup an entire car's aerodynamic balance for racing. Without this data, you can only guess at what other products out there do.

Rigidity: Neither the splitter nor the bumper are the most rigid pieces out there. The splitter does fairly well by itself, but the bumper is all plastic and bows with much load added. That is why we are producing and coming out with a race splitter kit. This upgrade kit will add 34% more downforce with a minimal drag increase, and include a splitter tie rod kit that adds support directly to the crash beam. If you add a splitter tie to anywhere that isn't metal (APR's goes to the plastic bumper in all the photos I have looked at), the splitter tie is in no way holding much load, if any.

Leading Edge Design: The whole trick with these splitters was to produce something that was affordable to the masses. While a contoured leading edge would be beneficial, we did not have the ability to do this cheaply. That sharp edge is great for cutting people's ankles as well !

I think I answered most of the questions.

Thanks,
Eric

It is nice of you to explain like this. I always roll my eyes at the mention of proprietary polymer and such on an item that wouldn't ever recoup the millions required to develop a good new formula (or be anywhere close to the value of selling such materials to others). It is reassuring that you are willing to directly address the marketing speak.

I would not order something with such a blatantly false statement regarding its material (if a manufacturer doesn't know enough about the material to know it isn't proprietary then what can I expect from the manufacturing quality?). This way we know that you put in actual effort to find a suitable material.

[dradernh]

Originally Posted by Reaper

im surprised there aren't more homemade splitters popping up. Some of these companies charge a premium for flat stock. The ft86sf one is at least a good price and is water jet cut, so its at least made out of something relatively hard. Im about to just buy a big flat chunk of ABS and cut it up with a jig saw after seeing some of the prices on something im going to smash the hell out of.

I've got one made out of 3/8" MDO, although it's a race shop-made piece, so not strictly homemade. It's rigid (MDO = plywood) and supported by four large turnbuckles mounted to the metal bumper. A homemade splitter is an excellent project for the DIYer with moderate skills and patience; a retail piece like the one being discussed, of course, makes the most sense for most owners.

Re: "something im going to smash the hell out of." – Some drivers, especially racers, figure this out ahead of time and make plans for timely replacement by having a spare handy.

[eric6]

Originally Posted by ddeflyer

It is nice of you to explain like this. I always roll my eyes at the mention of proprietary polymer and such on an item that wouldn't ever recoup the millions required to develop a good new formula (or be anywhere close to the value of selling such materials to others). It is reassuring that you are willing to directly address the marketing speak.

I would not order something with such a blatantly false statement regarding its material (if a manufacturer doesn't know enough about the material to know it isn't proprietary then what can I expect from the manufacturing quality?). This way we know that you put in actual effort to find a suitable material.

Thanks. We never intended to come across that way. I am glad we got that cleared up for you guys involved.

Originally Posted by dradernh

I've got one made out of 3/8" MDO, although it's a race shop-made piece, so not strictly homemade. It's rigid (MDO = plywood) and supported by four large turnbuckles mounted to the metal bumper. A homemade splitter is an excellent project for the DIYer with moderate skills and patience; a retail piece like the one being discussed, of course, makes the most sense for most owners.

Re: "something im going to smash the hell out of." – Some drivers, especially racers, figure this out ahead of time and make plans for timely replacement by having a spare handy.

This is something we can offer for customers as well. Nearly half of the price of the splitters comes from hardware and the rivet-nut installation tool. We can look into offering replacement splitters with no hardware for those of you that will inevitably need a replacement.

[D K]

You could always buy it as a straight edge and later run a router over it...

I doubt th difference between a radiused leading edge vs. a straight edge would even be quantifiable on our cars.

D

Originally Posted by dradernh

Meaning that the final design was the result of, say, a half-dozen or a dozen different iterations run through the software, resulting in this design being the best compromise in terms of downforce and, given the target market, practicality of installation, as well as pricing? If so, I wonder what results the designer got when he tested with a radiused leading edge (when viewed edge-on), and why that edge isn't a part of the present design. It would also be interesting to see the result produced by a rounded shape at the leading edge (when seen from above), as opposed to one that follows the design of the bumper cover.

These CFD-generated images using a generic street car shape give an idea of why a designer might choose a radiused leading edge:

[civicdrivr]

Originally Posted by eric6

Rigidity: Neither the splitter nor the bumper are the most rigid pieces out there. The splitter does fairly well by itself, but the bumper is all plastic and bows with much load added. That is why we are producing and coming out with a race splitter kit. This upgrade kit will add 34% more downforce with a minimal drag increase, and include a splitter tie rod kit that adds support directly to the crash beam. If you add a splitter tie to anywhere that isn't metal (APR's goes to the plastic bumper in all the photos I have looked at), the splitter tie is in no way holding much load, if any.

@glamcem

[dradernh]

Originally Posted by D K

I doubt the difference between a radiused leading edge vs. a straight edge would even be quantifiable on our cars.

Even at the low level of downforce being generated by the Hancha/FT-86 Speed Factory splitter, if Eric ran a sim with a radiused edge the difference would be quantifiable. If he's done that, it would be instructive to see the change in downforce.

I would guess that he's already done it, if only out of curiosity, unless perhaps he's using a service, having to pay for each run, and knew he wasn't ever going to be offering a radiused edge in the first place. I'm a data guy, so that drives my curiosity regarding subjects like this.

[gramicci101]

Paul does all that. They have their own machines to do the CFD, but they've said it takes around 24 hours to run a single simulation. After they've built the model, which isn't a quick process either.

[glamcem]

Originally Posted by civicdrivr

@glamcem

Dude I know this I already added rods even before they released their upgrade kit.as I said earlier it's not the best solution but it's still better than nothing right? Also splitter itself creates about 23 lbs downforce as of now and I tested at track,ran off the track and nothing happened ..yet you are still trying to prove your point lol

[plucas]

Originally Posted by dradernh

Meaning that the final design was the result of, say, a half-dozen or a dozen different iterations run through the software, resulting in this design being the best compromise in terms of downforce and, given the target market, practicality of installation, as well as pricing? If so, I wonder what results the designer got when he tested with a radiused leading edge (when viewed edge-on), and why that edge isn't a part of the present design. It would also be interesting to see the result produced by a rounded shape at the leading edge (when seen from above), as opposed to one that follows the design of the bumper cover.

These CFD-generated images using a generic street car shape give an idea of why a designer might choose a radiused leading edge:

Rounded edge is pointless for the fact that it cannot be manufactured in our price range. Why analyse something that won't represent the final product? Btw even if it was only a dozen simulations (which it was more), that would be over two weeks of JUST CFD TIME. CFD isn't some magical program that you insert a model and click run. It requires a lot of setup time a knowledge to make sure everything is correct. I could go into detail about this and the time involved, but most wouldn't understand.

Also a leading round edge isn't always a good thing if you are targeting downforce. Our sharp edge is actually doing something to make downforce, but I am not giving out that information. I will say though, rounding the edge would decrease some drag.

Originally Posted by dradernh

Even at the low level of downforce being generated by the Hancha/FT-86 Speed Factory splitter, if Eric ran a sim with a radiused edge the difference would be quantifiable. If he's done that, it would be instructive to see the change in downforce.

I would guess that he's already done it, if only out of curiosity, unless perhaps he's using a service, having to pay for each run, and knew he wasn't ever going to be offering a radiused edge in the first place. I'm a data guy, so that drives my curiosity regarding subjects like this.

It might be quantifiable. Might...

We do all of our engineering and analysis work in house. We both, Eric and I design parts and I do the analysis work. You might be a data guy, but data can be misleading unless you really know what you are looking at.

Originally Posted by gramicci101

Paul does all that. They have their own machines to do the CFD, but they've said it takes around 24 hours to run a single simulation. After they've built the model, which isn't a quick process either.

This is correct and thank you!

[kavanagh]

I watched Eric step on the front of his a couple days ago, and it compressed the suspension instead of deflecting or deforming the bumper. Money well spent in my opinion when it comes with the rods.


Sent from a secret volcano base using trained sharks

[D K]

Originally Posted by dradernh

Even at the low level of downforce being generated by the Hancha/FT-86 Speed Factory splitter, if Eric ran a sim with a radiused edge the difference would be quantifiable. If he's done that, it would be instructive to see the change in downforce.

I would guess that he's already done it, if only out of curiosity, unless perhaps he's using a service, having to pay for each run, and knew he wasn't ever going to be offering a radiused edge in the first place. I'm a data guy, so that drives my curiosity regarding subjects like this.

Quantifiable to what extent?

Im sure there are plenty of ways to make this splitter imcrimentaly more efficient, but how far do you want to take this?

Looking at lap time, would the rounded edge give you another second? No.
Another 1/10th? No.

There are so many other areas where you can shave a 1/10th easier and cheaper.
So, it's not worth it to take it to that extreme.

Besides, one could always run a router over it after the fact if a person was so inclined.
For me, it's not woth it.

Ill take 95% efficiency at 75% cost almost any time.

[gramicci101]

Originally Posted by plucas

Also a leading round edge isn't always a good thing if you are targeting downforce. Our sharp edge is actually doing something to make downforce, but I am not giving out that information. I will say though, rounding the edge would decrease some drag.

What about instead of a plain half circle rounded leading edge, you had an airfoil-shaped leading edge? Just with the more curved side on the bottom. Like a slight teardrop shape under the first few inches of the leading edge. That would (possibly) create faster airflow and a low pressure zone under the nose, generating an almost suction effect.

Like so:


That would probably be easier to do in CF than it would be in plastic sheet, which would greatly increase the time and cost. It's a novel idea though.

I wish I had access to the tools you guys have. I have a ton of probably useless ideas backed by absolutely no formal education or testing that I want to play around with.