NineLivesRacing Rear Diffuser

DCMoney

Goblin Guru
Making some assumptions:
12guage 5052, 32"x48" Main sheet

2.06mm x 812.8 x 1219.2 = 2,041,389 mm^3
2,041,389 * 2.7 g/ cm^3 = 5511.75g -> 12.15lbs

Another wild guess saying the ribs are all ~10% of the main sheets volume:
12.15 +1.2 = ~13.35 lbs total weight

I was going to guess 15 lbs or so...
Not sure what the thickness of 12 gauge aluminum is, google tells me its ~.080" which is really thin to be exposed to the stresses it'll see bolted to a vehicle, and not the easiest to to weld, constant dynamic beating by the road is going to fatigue those welds in no time if its .080". FYI Typically aluminum sheets are purchased in decimal thickness. I would assume the main plate of the diffuser is at least .100" maybe .125" for extra strength. This calculator is a good recourse for sheet weights. https://www.onlinemetals.com/en/weight-calculator

Dastrup you going to vacuum your oil out for oil changes or drop the diffuser?

Sometimes I wish I was still at my old job, but only when it comes to making **** like this, could have made it out of our scrap material.

32" x 48" x .125" sheet in this example (18lb), with .125" thick fins total weight is 25# inner fins looks thinner in Dastrups pics, but whatever.

.100" AL for all components, 20# total.

Screenshot 2021-07-22 121402.png
 

dastrups

Well-Known Member
Not sure what the thickness of 12 gauge aluminum is, google tells me its ~.080" which is really thin to be exposed to the stresses it'll see bolted to a vehicle, and not the easiest to to weld, constant dynamic beating by the road is going to fatigue those welds in no time if its .080". FYI Typically aluminum sheets are purchased in decimal thickness. I would assume the main plate of the diffuser is at least .100" maybe .125" for extra strength. This calculator is a good recourse for sheet weights. https://www.onlinemetals.com/en/weight-calculator

Dastrup you going to vacuum your oil out for oil changes or drop the diffuser?

Sometimes I wish I was still at my old job, but only when it comes to making **** like this, could have made it out of our scrap material.

32" x 48" x .125" sheet in this example (18lb), with .125" thick fins total weight is 25# inner fins looks thinner in Dastrups pics, but whatever.

.100" AL for all components, 20# total.

View attachment 25427
I will just unbolt it to change the oil. We'll see how I get on with it. Does seem on the thinner end. I would have liked it to be a bit thicker even if it adds some weight.
 

Waterdriver

Goblin Guru
Not sure what the thickness of 12 gauge aluminum is, google tells me its ~.080" which is really thin to be exposed to the stresses it'll see bolted to a vehicle, and not the easiest to to weld, constant dynamic beating by the road is going to fatigue those welds in no time if its .080". FYI Typically aluminum sheets are purchased in decimal thickness. I would assume the main plate of the diffuser is at least .100" maybe .125" for extra strength. This calculator is a good recourse for sheet weights. https://www.onlinemetals.com/en/weight-calculator

Dastrup you going to vacuum your oil out for oil changes or drop the diffuser?

Sometimes I wish I was still at my old job, but only when it comes to making **** like this, could have made it out of our scrap material.

32" x 48" x .125" sheet in this example (18lb), with .125" thick fins total weight is 25# inner fins looks thinner in Dastrups pics, but whatever.

.100" AL for all components, 20# total.

View attachment 25427
I have a 48"x 48" road sign I had thought about using as a diffuser but it is way too heavy. I dont recall the thickness but seems to weigh between 20-30lbs by itself. It would drop some weight after removing the decal, but still.
Either fiberglass or CF seems the way to go.
 

KSLunsfo

Well-Known Member
By the time you weld in the ribs and bolt the thing in place you create a pretty good bit of strength. But I do agree a 12 gauge may be on the thin side. I somewhat arbitrarily chose that as some kind of starting point. Proper thing to do would be talking to people in the industry (like 9lives) to see what thickness they see being used for a rear diffuser like this.
 

OptimizePrime

Goblin Guru
Just as FYI, 9LR added the Diffuser to the dropdown on their website (url in first post). $725 + shipping

I messaged Johnny Cichowski on Facebook, who seems to be active on their 9LR posts in the DF Goblin board, about offering up my Goblin for legit mounts and to use as a prototype for actual front wang mounts.... not expecting anything to come of it though.
 

Chris_WNC

Well-Known Member
The shop I work at got a 3kw fiber laser cutter in April. If you guys get to the point that you want some prototype aluminum parts laser cut let me know. I can work with napkin drawings up to DXF files. One-offs are fine.

CHRIS
 

TheNuker

Goblin Guru
The shop I work at got a 3kw fiber laser cutter in April. If you guys get to the point that you want some prototype aluminum parts laser cut let me know. I can work with napkin drawings up to DXF files. One-offs are fine.

CHRIS
The shop I work at got a 3kw fiber laser cutter in April. If you guys get to the point that you want some prototype aluminum parts laser cut let me know. I can work with napkin drawings up to DXF files. One-offs are fine.

CHRIS

Noice! I have a 2kW fiber laser coming around the end of the year. Really excited for that!

Nuker-
 

kalishek

Well-Known Member
Curious about the top cutouts on the 'big wang' end plates. Would spill air from top of wing and make it less effective? Or is it to reduce drag by lessening vortex generated by wing?? End plates are used to used to make a wing area more effective by not allowing the air to spill off over the sides. Have seen manufactures mill slots in end plates to fine tune down force generated (Radical RXC comes to mind) but not such a large cut out.
KAL
 

k.rollin

Goblin Guru
Curious about the top cutouts on the 'big wang' end plates. Would spill air from top of wing and make it less effective? Or is it to reduce drag by lessening vortex generated by wing?? End plates are used to used to make a wing area more effective by not allowing the air to spill off over the sides. Have seen manufactures mill slots in end plates to fine tune down force generated (Radical RXC comes to mind) but not such a large cut out.
KAL
Those are the CFD endplates, so the purpose of the cut outs is to minimize drag. They're an additional option for all the single element wings they offer.
 

Waterdriver

Goblin Guru
As K.Rollin stated, the cut out reduces drag. It does this by creating an opposite rotation vortex to reduce the overall vortex thats generated. Minimizing the vortex generated equals less drag.
 

JPas914

Well-Known Member
Recieved my diffuser last week, extremely well made part. Package weight was 20lbs, but ~5lbs of that was cardboard. Finally got around to installing it today. I used the bolt holding the rear brake T-ftting to center the diffuser in the front, and then marked the center points on the rear of the car and diffuser. After everything was lined up, I just used some unused holes on the subframe as mounting locations. Haven’t dragged it on anything yet, but my drive to work doesn’t have any speed bumps.
 

Attachments

Sparvy

Active Member
Recieved my diffuser last week, extremely well made part. Package weight was 20lbs, but ~5lbs of that was cardboard. Finally got around to installing it today. I used the bolt holding the rear brake T-ftting to center the diffuser in the front, and then marked the center points on the rear of the car and diffuser. After everything was lined up, I just used some unused holes on the subframe as mounting locations. Haven’t dragged it on anything yet, but my drive to work doesn’t have any speed bumps.
I got mine last week as well and was wondering how others mounted it up. With the tabs sticking up from the bottom it looks like they will get bent/crushed when mounted. What size bolts did you end up using? I was considering some nut- serts with cap head Allen bolts.
 

JPas914

Well-Known Member
I got mine last week as well and was wondering how others mounted it up. With the tabs sticking up from the bottom it looks like they will get bent/crushed when mounted. What size bolts did you end up using? I was considering some nut- serts with cap head Allen bolts.
I used 3.5 inch long 3/8dia for the front/middle holes and 4.5in long 7/16ths bolts for the rear where the rear-most sway bar bols would have gone. And used the 1/4dia bolt holding the brake-T to support the front center.
 
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