Custom Rear Bottom Diffuser for NISMO bumper
02-06-2012, 03:14 AM
#23
Most for looks
Hey,lets be realistic...sure some guys will want a rear diffuser because
the value in their eyes is that it is fully functional and delivers ----downforce.
But most would buy for the looks...how it blends into the lines of the car.
How it will make their Nismo unique.
Sometimes functional can be ugly.
You got a winner if it can be functional AND good looking.
the value in their eyes is that it is fully functional and delivers ----downforce.
But most would buy for the looks...how it blends into the lines of the car.
How it will make their Nismo unique.
Sometimes functional can be ugly.
You got a winner if it can be functional AND good looking.
02-06-2012, 06:27 AM
#27
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It's more than just the shape of the car that we would need a 3D of, it's also the bottom of the car. Since the bottom of the car is not flat, we don't really know what the air is doing. This is what will probably have the greatest impact on how effective the diffuser will be.
S&R built an aluminum one for George's Z with a 15 degree (may be more) rake and it functions well. Since it was made for a standard Z bumper, it is useless to me. However, since it did work well just from straight cuts of aluminum and large rake, a nicely fit and "curved" diffuser should fair even better.
We will be making additional pieces to flatten the bottom of the car. I am not sure how that will affect temps at this moment. Of course we will vent it to channel air to the back above the piece but that doesn't mean it will cool just as effeciently as it did prior to making the flat bottom. This part of it is going to require multiple designs and probably months of trials.
We will be finalizing the initial design of it today and will probably have it put in Solidworks tomorrow. Once that is done, we can "tune" it by continually running a flow analysis on it.
I will post up the CFD images as well during when we complete that portion.
If this works well, we plan on making on for the standard 350Z, standard 370Z and Nismo 370Z as well.
Maybe at some point through all of this I will finally get a 3D scanner. Then the real fun begins.. lol
S&R built an aluminum one for George's Z with a 15 degree (may be more) rake and it functions well. Since it was made for a standard Z bumper, it is useless to me. However, since it did work well just from straight cuts of aluminum and large rake, a nicely fit and "curved" diffuser should fair even better.
We will be making additional pieces to flatten the bottom of the car. I am not sure how that will affect temps at this moment. Of course we will vent it to channel air to the back above the piece but that doesn't mean it will cool just as effeciently as it did prior to making the flat bottom. This part of it is going to require multiple designs and probably months of trials.
We will be finalizing the initial design of it today and will probably have it put in Solidworks tomorrow. Once that is done, we can "tune" it by continually running a flow analysis on it.
I will post up the CFD images as well during when we complete that portion.
If this works well, we plan on making on for the standard 350Z, standard 370Z and Nismo 370Z as well.
Maybe at some point through all of this I will finally get a 3D scanner. Then the real fun begins.. lol
02-06-2012, 10:47 AM
#31
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S&R built an aluminum one for George's Z with a 15 degree (may be more) rake and it functions well. Since it was made for a standard Z bumper, it is useless to me. However, since it did work well just from straight cuts of aluminum and large rake, a nicely fit and "curved" diffuser should fair even better.
02-06-2012, 12:56 PM
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Here is a link to S&R's facebook album with images of the aluminum rear diffuser they made for George's car.
http://www.facebook.com/#!/media/set...2905773&type=1
Kingbaby,
I understand what you are saying but there a couple things to this diffuser.
First, it's made of metal so "shaping" it and making smooth radiuses it a pain.
It actually isn't finished either. In other words, idealy the diffuser should cover everything from the rear of the tires, all the way back to it's exit.
The trasition of the flat, beginning portion to where it begins to slope up needs to be as smooth as possible. Also the rake itself makes a difference too based on the transition from the flat part.
Picure you are ski'ing down a slope. You are the air, the slope is the diffuser. If you are ski'ing down the slop at a 45 degree angle and it suddenly goes to a 15 degree angle, what happens? You would no longer be on the slope. Now picture that in reverse. If the air is following the flat part of the diffuser and then it suddenly goes to a 45 degree angle, it will no longer be following the slope because the change was too immediate.
They have not made it to a completely finished product because they have customers cars to work on so it takes the back seat.
Once they finish it, it will be a nice piece and very durable. In the mean time, I will be doing a Nismo one from glass and carbon fiber :-)
http://www.facebook.com/#!/media/set...2905773&type=1
Kingbaby,
I understand what you are saying but there a couple things to this diffuser.
First, it's made of metal so "shaping" it and making smooth radiuses it a pain.
It actually isn't finished either. In other words, idealy the diffuser should cover everything from the rear of the tires, all the way back to it's exit.
The trasition of the flat, beginning portion to where it begins to slope up needs to be as smooth as possible. Also the rake itself makes a difference too based on the transition from the flat part.
Picure you are ski'ing down a slope. You are the air, the slope is the diffuser. If you are ski'ing down the slop at a 45 degree angle and it suddenly goes to a 15 degree angle, what happens? You would no longer be on the slope. Now picture that in reverse. If the air is following the flat part of the diffuser and then it suddenly goes to a 45 degree angle, it will no longer be following the slope because the change was too immediate.
They have not made it to a completely finished product because they have customers cars to work on so it takes the back seat.
Once they finish it, it will be a nice piece and very durable. In the mean time, I will be doing a Nismo one from glass and carbon fiber :-)
Last edited by GAMERMODZoCOM; 02-06-2012 at 02:54 PM.
02-07-2012, 06:20 PM
#36
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Why would you do that? If you cover up tranny and also your pipes and dif you will have major overheating problems when on the track. The wind is what cools them down. And if you cover up pipes that heat will just stay there and make the tranny and diff even hotter.
You might wana do some more looking into before you try to get into this and compete with the big jap guys. Cause honestly the way the back end of the nismo is setup, is well done. For track (as long as your nismo is lower then factory) or hard city driving.
You might wana do some more looking into before you try to get into this and compete with the big jap guys. Cause honestly the way the back end of the nismo is setup, is well done. For track (as long as your nismo is lower then factory) or hard city driving.
02-07-2012, 07:00 PM
#38
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Why would you do that? If you cover up tranny and also your pipes and dif you will have major overheating problems when on the track. The wind is what cools them down. And if you cover up pipes that heat will just stay there and make the tranny and diff even hotter.
You might wana do some more looking into before you try to get into this and compete with the big jap guys. Cause honestly the way the back end of the nismo is setup, is well done. For track (as long as your nismo is lower then factory) or hard city driving.
You might wana do some more looking into before you try to get into this and compete with the big jap guys. Cause honestly the way the back end of the nismo is setup, is well done. For track (as long as your nismo is lower then factory) or hard city driving.
The rear nismo diffisuer is nice but does not function like a rear lower diffuser. The NISMO rear allows air to not become trapped like a parachute but does not function as a rear diffuser that creates downforce.
I think I need to reiterate that fact this is also not being approached by just slapping some fiberglass panel together and that it is being CFD'd so everyone can see the flow analysis.
It would cost somewhere in the neiborhood of 30k just to scan an entire car, then engineering cost of around 40k to design an absolutely perfect diffuser, plus wind tunel time, track test time, etc. You would be in a "perfect" diffuser design for well over 150k before tooling costs.
Now lets say we spent 150k on this and we sold each diffuser at $600.00. We would have to sell 250 diffusers just to break even on design and tooling. You would then have to sell many more to cover the overhead it took to market, sell, pack, ship, etc of them so more than likely, you are going to have to sell about 325 of them before you "start making money" from it.
Do you think this is how it's always done? I can tell you for a standard car like ours, it's rarely done this way in Japan or the US. Also for the NISMO, how much of that market are you really going to capture? Maybe 2% - 4% if your lucky.
Please keep in mind as well that the difference between 100% perfect and, what I feel, is an easily achievable 90%+ perfect will not be noticable on our cars.
02-07-2012, 08:37 PM
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We have taken many different designs in to concideration and still will during development.