Front Splitter and Bumper combo

victorofhavoc · 11-24-2020, 06:13 PM

Updated the OP... Looks like I'm going down the make your own dry carbon rabbit hole... I should be able to pop out splitters at 230-320$ consumables cost depending on carbon or Kevlar design, quality, and color.

victorofhavoc · 12-07-2020, 11:38 AM

In the past few weeks I made some time to order some carbon, do a good amount of reading on aero theories (I have a very good conceptual and practical understanding of physics in my educational background), and start putting a few things together.

Fun stuff first, I ordered all of the carbon and carbon Kevlar I plan to use for the splitter and it arrived very quickly! I also ordered some high temp and high impact epoxy resin with a 1 hour pot life. This is the same stuff that Boeing uses, and the same stuff some of the indy car builders use. It's only a 1 hr life so I will have to move very quickly, and it also requires a higher temp cure time. This resin is the only part I'm nervous about and resin is really the key to the whole thing! I bought a black commercial grade twil carbon since it was only 12$ per yard and weighs 203 grams per square meter. It will form the two base layers of structural carbon to my splitter. I also got the digital red camo carbon Kevlar, which is an absolutely beautiful product in person and really cannot be described or photographed well. It will form my top layer and should be the most durable. As I wear through it and black carbon is exposed I should be able to make repairs with my left over material!

I got the bumper off and made a cardboard air dam to start. I'm still not 100% certain how to best cut an air dam to shape that will fit the curves of the front bumper, but I traced what I had to make a basic start and it's starting to resemble a splitter!

Moving on, I got some hardware to mount up my professional awesome quick releases. It will be two u bolts per quick release with two angle brackets so that the u bolts clamp to the crash beam, the L brackets are bolted to the u bolts, and the quick releases then adjust up and down the L bracket as well as allowing the adjustment up and down the u bolt.

If anyone else plans to jump down a similar rabbit hole, I highly recommend looking at professional awesome's diy front aero page, https://professionalawesome.com/diy-downforce/ . I did a tremendous amount of reading about a lot of other aero concepts after using their page as a starting point. There's really a lot to go down, but one of the key aspects which I didn't realize until I read about it, is that the Battle Aero wing that came with my car had endplates facing the wrong way

. The meat of the plate should always be at the front of the wing. Also, the wing shape isn't ideal, but it's not bad. It's prone to a bit more drag than a typical wing used in motorsport with data behind it, and there's a lot of improvement to be had from going to a dual element air foil, so at some point I guess I might even try my hand at a carbon wing... Pictured below is the CORRECT orientation of the endplates. This should help reduce a tremendous amount of drag and improve downforce at the outsides of the wing. This is especially needed given the width of the Z's front and rear fenders which greatly disturb the air flow underneath the ends of the air foil.

I measured out the radiator and the front grill intake as well. As it turns out the front grill intake (the functional parts not the plastic) are sized exactly 1/3rd of the surface area of the cooling stack! That's exactly how it should be! Who would have guessed nissan engineers knew what they were doing!? Now I just need to cut out the obstructive plastic and create a curved intake panel that will reach to the edges of the radiator to seal all that air in and force it through the cooling stack. With some louvres this should help keep all temps greatly in check and reduce underhood pressure at speed, which will lead to more downforce! I also plan to use the oem vertical DRL as an intake for the brake ducts. I checked and a shopvac general purpose suction end fits the size, so I may try to glue one on and see how it goes! Likely the intake will have to be downsized eventually, but that's not so hard to do...

So here's the major problem at the moment!! I bought a venturi vac to generate my vacuum suction for the resin catch which then sucks from the bag. I hooked everything up and I was missing several fittings. After a trip to home depot racing, I got all the fittings I needed and test the vac. It immediately pulled 27"hg but the cost was high... It needed a minimum 55 psi @ 3.5 cfm to maintain that vac and while my compressor can run 5cfm at 90psi, it only runs 3.5 cfm @ 165 psi and coincidentally that's where it got stuck on recharge and would run perpetually! It obviously would never get back to its 200psi full charge. There are other venturi that perform better and generate 1atm or 29"hg at only 0.5 cfm, but those cost as much as a knockoff vac pump on Amazon, so I went ahead and bought the vac pump. It should arrive this week for more testing!

Rusty · 12-07-2020, 12:22 PM

Steep learning curve.

Keep in mind the suspension travel. You don't want the splitter to low to where it scraps all the time. I've hit a G out at speed and scrapped the whole bottom of the splitter.

Hotrodz · 12-07-2020, 01:28 PM

Agreed, I did not have splitter supports and just lifting at 140 mph brought the splitter in contact with the road. Not good!

Sent from my SM-G965U using Tapatalk

Hotrodz · 12-07-2020, 01:30 PM

Also, if you email those guys at Profesional Awesome Racing they may provide you with free advice. They have help me out a ton with my stuff.

Sent from my SM-G965U using Tapatalk

victorofhavoc · 12-07-2020, 02:21 PM

Quote:

Originally Posted by Hotrodz

Also, if you email those guys at Profesional Awesome Racing they may provide you with free advice. They have help me out a ton with my stuff.

Sent from my SM-G965U using Tapatalk

Yep, I've been working with them actually! They've given me some good advice so far and I have their front support hardware that has titanium pucks on the bottom to protect the splitter in certain impacts. I'll likely add a couple more titanium skids on the sides. They're not cheap at 30$ a pop, but not the worst either.

My measurements so far indicate I will be a bit over 3 inches from splitter to ground. The front springs are 14k and dampening is currently a bit on the soft end. I believe I'll have to up compression and rebound both a bit to account for the splitter but we'll see.

Did my images post for anyone else? I'm looking at my post now and don't see them at all...

Hotrodz · 12-07-2020, 02:37 PM

Cool, the pictures did not post.

Rusty · 12-07-2020, 05:04 PM

Quote:

Originally Posted by Hotrodz

Cool, the pictures did not post.

2011 Nismo#91 · 12-08-2020, 06:34 AM

Quote:

Originally Posted by victorofhavoc

Updated the OP... Looks like I'm going down the make your own dry carbon rabbit hole... I should be able to pop out splitters at 230-320$ consumables cost depending on carbon or Kevlar design, quality, and color.

You have access to an autoclav big enough for a splitter?

victorofhavoc · 12-08-2020, 04:28 PM

Quote:

Originally Posted by 2011 Nismo#91

You have access to an autoclav big enough for a splitter?

You don't need an autoclave unless you're using an epoxy resin that requires high temp cure or you're trying to drastically accelerate your cure process. Prepreg also often requires a high temp or autoclave cure due to the nature of producing a carbon which contains a gelled resin.

The resin I chose is high impact and high temp (325*) with a 1 hour pot life and should take approximately 24 hrs to cure at room temp. The same epoxy can be cured for 18 hrs at room temp and 6 hrs at 185* to have a 450* temp resistance, but that also requires a different catalyst.

Edit: If you're referring to the use of "dry carbon" vs "wet carbon" in context, technically laying down your own resin layers is considered "wet" by the newer definitions but adding in the vacuum process and layering the resin/epoxy with a final higher cure temp also produces a "dry carbon". The goal is to get to 40% resin by weight to carbon and most well done vacuumed setups can get you pretty close. When I first worked with carbon in 2007 anything with resin content below 60% was considered "dry carbon".

victorofhavoc · 12-08-2020, 04:37 PM

Quote:

Originally Posted by Rusty

fixed the pictures!

static links look like they were broken

victorofhavoc · 03-22-2021, 05:07 PM

So I have totally neglected this thread, and I feel it's time for an update. I am super close to being done with the splitter! I decided to add diffusers, which further complicated my design!

So initially I ran into an issue with tracing the bumper accurately, especially considering there's some body damage in the bumper/fender area on the driver side, so it's sunken in by about an inch. There's also a bit of a chicken and egg scenario with mounting up plywood and choosing where to put initial mounts. This took me a lot of tinkering, but eventually I decided to use rivnuts and mount on the aluminum chassis support that goes to the crash beam. From here I used my Professional Awesome Racing quick releases to mount up the plywood, and trace out the bumper. I used a flexible pvc wall to make a vertical surface from the bumper down. After a ton of measuring I lined everything back up and traced out onto wax paper to make a half of the splitter, including the end to the axle. Once I had that, I traced onto the pvc wall to make a firm template, and then extended it 6 inches from every point to create the final sizing.

I then decided to go one step further and began designing diffusers to fit the splitter. I spoke with Professional Awesome and determined to go with a fairly large diffuser setup due to the size of the rear wing. I also decided that adding a gurney flap to the rear wing would be great for helping balance out the extra front end downforce that will exist. I began with the idea of the curved diffuser based on Pro Awe's design but scaled to 82.5% size to fit under the shorter bumper of the Z with the full intention of dumping all air into the wheel well. Unfortunately after a ton of time attempting to design this complex shape I almost gave up entirely. I decided to use CAD to try and design it then have it 3d printed. Unfortunately this proved too much for my cad skills so I decided to shape a more square diffuser that's 85% scale, but would still dump all air into the wheel well. The grey design below is the curved failure because I couldn't figure out how to get the multi-dimensional dynamic curvature to be concave on the upper surface with my limited CAD skillset. Instead I designed a secondary model that's in red below.

The final printed images turned out okay, but they had quite a bit of warping to them. I should be able to still make them work by gluing some steel to them, which was necessary anyway to prevent the epoxy/carbon mixture from sticking to the surface. Also, I had to split each into 2 parts so that it could be printed in the limited size of most 3D printers.

The final splitter shape has been cut, and the side winglets I made are looking pretty good! They still have to be cut to shape and eventually glued to the splitter itself, but that won't be long now! Mainly I just have to finish the diffuser molds and cut the foam to fit the diffusers exactly.

Rusty · 03-22-2021, 07:04 PM

Your splitter should go all the way back to the wheel openings. There, you should put uprights on the end of the splitter.

victorofhavoc · 03-22-2021, 08:50 PM

It goes all the way back to the front of the front axle.

The mounting so far is two quick release mounts at the chassis and two fiberglass rods with titanium pucks split at the front. Total 6 points of contact pulling up at a 1.226 square inch area each. The carbon is 5 layers and there's 6th layer of carbon Kevlar. The sum should be something like 22000 psi. Are you saying with this mounting you think there won't be enough support? I really thought there would be plenty and pro awe hasn't mentioned needing more mounting at this point. :/

Rusty · 03-22-2021, 10:50 PM

Quote:

Originally Posted by victorofhavoc

It goes all the way back to the front of the front axle.

The mounting so far is two quick release mounts at the chassis and two fiberglass rods with titanium pucks split at the front. Total 6 points of contact pulling up at a 1.226 square inch area each. The carbon is 5 layers and there's 6th layer of carbon Kevlar. The sum should be something like 22000 psi. Are you saying with this mounting you think there won't be enough support? I really thought there would be plenty and pro awe hasn't mentioned needing more mounting at this point. :/

I should have said wing tips, instead of uprights.

11-24-2020, 06:13 PM	#31 (permalink)
victorofhavoc Base Member Join Date: Oct 2011 Location: Kansas City Posts: 229 Drives: 2014 370z Rep Power: 14	Updated the OP... Looks like I'm going down the make your own dry carbon rabbit hole... I should be able to pop out splitters at 230-320$ consumables cost depending on carbon or Kevlar design, quality, and color. JARblue, DarkJak, Rusty and 3 others like this. __________________ Had a 2010 WRX- boy was it quick in a straight line, got a 2014 Z- man is she grippy in the corners-- then left the Z and later got a GTI, now back in an 09 racecar Z!

12-07-2020, 11:38 AM	#32 (permalink)
victorofhavoc Base Member Join Date: Oct 2011 Location: Kansas City Posts: 229 Drives: 2014 370z Rep Power: 14	In the past few weeks I made some time to order some carbon, do a good amount of reading on aero theories (I have a very good conceptual and practical understanding of physics in my educational background), and start putting a few things together. Fun stuff first, I ordered all of the carbon and carbon Kevlar I plan to use for the splitter and it arrived very quickly! I also ordered some high temp and high impact epoxy resin with a 1 hour pot life. This is the same stuff that Boeing uses, and the same stuff some of the indy car builders use. It's only a 1 hr life so I will have to move very quickly, and it also requires a higher temp cure time. This resin is the only part I'm nervous about and resin is really the key to the whole thing! I bought a black commercial grade twil carbon since it was only 12$ per yard and weighs 203 grams per square meter. It will form the two base layers of structural carbon to my splitter. I also got the digital red camo carbon Kevlar, which is an absolutely beautiful product in person and really cannot be described or photographed well. It will form my top layer and should be the most durable. As I wear through it and black carbon is exposed I should be able to make repairs with my left over material! I got the bumper off and made a cardboard air dam to start. I'm still not 100% certain how to best cut an air dam to shape that will fit the curves of the front bumper, but I traced what I had to make a basic start and it's starting to resemble a splitter! Moving on, I got some hardware to mount up my professional awesome quick releases. It will be two u bolts per quick release with two angle brackets so that the u bolts clamp to the crash beam, the L brackets are bolted to the u bolts, and the quick releases then adjust up and down the L bracket as well as allowing the adjustment up and down the u bolt. If anyone else plans to jump down a similar rabbit hole, I highly recommend looking at professional awesome's diy front aero page, https://professionalawesome.com/diy-downforce/ . I did a tremendous amount of reading about a lot of other aero concepts after using their page as a starting point. There's really a lot to go down, but one of the key aspects which I didn't realize until I read about it, is that the Battle Aero wing that came with my car had endplates facing the wrong way . The meat of the plate should always be at the front of the wing. Also, the wing shape isn't ideal, but it's not bad. It's prone to a bit more drag than a typical wing used in motorsport with data behind it, and there's a lot of improvement to be had from going to a dual element air foil, so at some point I guess I might even try my hand at a carbon wing... Pictured below is the CORRECT orientation of the endplates. This should help reduce a tremendous amount of drag and improve downforce at the outsides of the wing. This is especially needed given the width of the Z's front and rear fenders which greatly disturb the air flow underneath the ends of the air foil. I measured out the radiator and the front grill intake as well. As it turns out the front grill intake (the functional parts not the plastic) are sized exactly 1/3rd of the surface area of the cooling stack! That's exactly how it should be! Who would have guessed nissan engineers knew what they were doing!? Now I just need to cut out the obstructive plastic and create a curved intake panel that will reach to the edges of the radiator to seal all that air in and force it through the cooling stack. With some louvres this should help keep all temps greatly in check and reduce underhood pressure at speed, which will lead to more downforce! I also plan to use the oem vertical DRL as an intake for the brake ducts. I checked and a shopvac general purpose suction end fits the size, so I may try to glue one on and see how it goes! Likely the intake will have to be downsized eventually, but that's not so hard to do... So here's the major problem at the moment!! I bought a venturi vac to generate my vacuum suction for the resin catch which then sucks from the bag. I hooked everything up and I was missing several fittings. After a trip to home depot racing, I got all the fittings I needed and test the vac. It immediately pulled 27"hg but the cost was high... It needed a minimum 55 psi @ 3.5 cfm to maintain that vac and while my compressor can run 5cfm at 90psi, it only runs 3.5 cfm @ 165 psi and coincidentally that's where it got stuck on recharge and would run perpetually! It obviously would never get back to its 200psi full charge. There are other venturi that perform better and generate 1atm or 29"hg at only 0.5 cfm, but those cost as much as a knockoff vac pump on Amazon, so I went ahead and bought the vac pump. It should arrive this week for more testing! Rusty and Hotrodz like this. __________________ Had a 2010 WRX- boy was it quick in a straight line, got a 2014 Z- man is she grippy in the corners-- then left the Z and later got a GTI, now back in an 09 racecar Z! Last edited by victorofhavoc; 12-08-2020 at 04:35 PM.

12-07-2020, 12:22 PM	#33 (permalink)
Rusty Ronin Samurai - Assassin Join Date: Dec 2011 Location: Fayettenam,Pennsyltucky Age: 68 Posts: 35,220 Drives: 2011 Nismo GM 6M Rep Power: 2684438	Steep learning curve. Keep in mind the suspension travel. You don't want the splitter to low to where it scraps all the time. I've hit a G out at speed and scrapped the whole bottom of the splitter. Hotrodz likes this. __________________ 浪人 - 殺し屋 "The Difficult Anytime, The Impossible By Appointment Only" http://www.the370z.com/members-370z-...o-journal.html

12-07-2020, 01:28 PM	#34 (permalink)
Hotrodz A True Z Fanatic Join Date: Aug 2012 Location: NW, AZ Posts: 9,330 Drives: 10 Nissan 370z Nismo Rep Power: 2684385	Agreed, I did not have splitter supports and just lifting at 140 mph brought the splitter in contact with the road. Not good! Sent from my SM-G965U using Tapatalk Rusty likes this. __________________ *Fast Intentions TT Installed and Tuned by Seb at SpecialtyZ 610whp 560tq:\|Fast Intentions 3" TT-TDX*\|SpecialtyZ/Fast Intentions 72 Row Oil Cooler\|SZ 6 Puck Clutch & Flywheel\|3GsCustoms\|Z1\|Wavetrac\|Hotchkis\|Whiteline \|Blitz\|Fortune Auto 500\|Fujimura\|SPL\|H&R\|TK\|TWM\|RPM Rollbar\|Sparco\|Next Level Performance\|TrackSpec\|AeroFlow Dynamics\|Pioneer\|

12-07-2020, 01:30 PM	#35 (permalink)
Hotrodz A True Z Fanatic Join Date: Aug 2012 Location: NW, AZ Posts: 9,330 Drives: 10 Nissan 370z Nismo Rep Power: 2684385	Also, if you email those guys at Profesional Awesome Racing they may provide you with free advice. They have help me out a ton with my stuff. Sent from my SM-G965U using Tapatalk Rusty likes this. __________________ *Fast Intentions TT Installed and Tuned by Seb at SpecialtyZ 610whp 560tq:\|Fast Intentions 3" TT-TDX*\|SpecialtyZ/Fast Intentions 72 Row Oil Cooler\|SZ 6 Puck Clutch & Flywheel\|3GsCustoms\|Z1\|Wavetrac\|Hotchkis\|Whiteline \|Blitz\|Fortune Auto 500\|Fujimura\|SPL\|H&R\|TK\|TWM\|RPM Rollbar\|Sparco\|Next Level Performance\|TrackSpec\|AeroFlow Dynamics\|Pioneer\|

12-07-2020, 02:37 PM	#37 (permalink)
Hotrodz A True Z Fanatic Join Date: Aug 2012 Location: NW, AZ Posts: 9,330 Drives: 10 Nissan 370z Nismo Rep Power: 2684385	Cool, the pictures did not post. Rusty likes this. __________________ *Fast Intentions TT Installed and Tuned by Seb at SpecialtyZ 610whp 560tq:\|Fast Intentions 3" TT-TDX*\|SpecialtyZ/Fast Intentions 72 Row Oil Cooler\|SZ 6 Puck Clutch & Flywheel\|3GsCustoms\|Z1\|Wavetrac\|Hotchkis\|Whiteline \|Blitz\|Fortune Auto 500\|Fujimura\|SPL\|H&R\|TK\|TWM\|RPM Rollbar\|Sparco\|Next Level Performance\|TrackSpec\|AeroFlow Dynamics\|Pioneer\|

03-22-2021, 05:07 PM	#42 (permalink)
victorofhavoc Base Member Join Date: Oct 2011 Location: Kansas City Posts: 229 Drives: 2014 370z Rep Power: 14	Updated progress So I have totally neglected this thread, and I feel it's time for an update. I am super close to being done with the splitter! I decided to add diffusers, which further complicated my design! So initially I ran into an issue with tracing the bumper accurately, especially considering there's some body damage in the bumper/fender area on the driver side, so it's sunken in by about an inch. There's also a bit of a chicken and egg scenario with mounting up plywood and choosing where to put initial mounts. This took me a lot of tinkering, but eventually I decided to use rivnuts and mount on the aluminum chassis support that goes to the crash beam. From here I used my Professional Awesome Racing quick releases to mount up the plywood, and trace out the bumper. I used a flexible pvc wall to make a vertical surface from the bumper down. After a ton of measuring I lined everything back up and traced out onto wax paper to make a half of the splitter, including the end to the axle. Once I had that, I traced onto the pvc wall to make a firm template, and then extended it 6 inches from every point to create the final sizing. I then decided to go one step further and began designing diffusers to fit the splitter. I spoke with Professional Awesome and determined to go with a fairly large diffuser setup due to the size of the rear wing. I also decided that adding a gurney flap to the rear wing would be great for helping balance out the extra front end downforce that will exist. I began with the idea of the curved diffuser based on Pro Awe's design but scaled to 82.5% size to fit under the shorter bumper of the Z with the full intention of dumping all air into the wheel well. Unfortunately after a ton of time attempting to design this complex shape I almost gave up entirely. I decided to use CAD to try and design it then have it 3d printed. Unfortunately this proved too much for my cad skills so I decided to shape a more square diffuser that's 85% scale, but would still dump all air into the wheel well. The grey design below is the curved failure because I couldn't figure out how to get the multi-dimensional dynamic curvature to be concave on the upper surface with my limited CAD skillset. Instead I designed a secondary model that's in red below. The final printed images turned out okay, but they had quite a bit of warping to them. I should be able to still make them work by gluing some steel to them, which was necessary anyway to prevent the epoxy/carbon mixture from sticking to the surface. Also, I had to split each into 2 parts so that it could be printed in the limited size of most 3D printers. The final splitter shape has been cut, and the side winglets I made are looking pretty good! They still have to be cut to shape and eventually glued to the splitter itself, but that won't be long now! Mainly I just have to finish the diffuser molds and cut the foam to fit the diffusers exactly. JARblue, Rusty, Hotrodz and 1 others like this. __________________ Had a 2010 WRX- boy was it quick in a straight line, got a 2014 Z- man is she grippy in the corners-- then left the Z and later got a GTI, now back in an 09 racecar Z!

03-22-2021, 07:04 PM	#43 (permalink)
Rusty Ronin Samurai - Assassin Join Date: Dec 2011 Location: Fayettenam,Pennsyltucky Age: 68 Posts: 35,220 Drives: 2011 Nismo GM 6M Rep Power: 2684438	Your splitter should go all the way back to the wheel openings. There, you should put uprights on the end of the splitter. Sharad909 likes this. __________________ 浪人 - 殺し屋 "The Difficult Anytime, The Impossible By Appointment Only" http://www.the370z.com/members-370z-...o-journal.html

03-22-2021, 08:50 PM	#44 (permalink)
victorofhavoc Base Member Join Date: Oct 2011 Location: Kansas City Posts: 229 Drives: 2014 370z Rep Power: 14	It goes all the way back to the front of the front axle. The mounting so far is two quick release mounts at the chassis and two fiberglass rods with titanium pucks split at the front. Total 6 points of contact pulling up at a 1.226 square inch area each. The carbon is 5 layers and there's 6th layer of carbon Kevlar. The sum should be something like 22000 psi. Are you saying with this mounting you think there won't be enough support? I really thought there would be plenty and pro awe hasn't mentioned needing more mounting at this point. :/ __________________ Had a 2010 WRX- boy was it quick in a straight line, got a 2014 Z- man is she grippy in the corners-- then left the Z and later got a GTI, now back in an 09 racecar Z!

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