rear diffusers
#1
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rear diffusers
who is running a rear diffuser. i would like to discuss design and see some pics.
i want to make one out of fiberglass to fit my car, with the wizdom bumper i bought. i have been reading online. what i see is that the magic number is 7 degrees of incline off your refference point (flatbottom of the car) . i want to make this thing go from the diff up to the bumper, i havent measured but off the top of my head its like 2ft in distance, at 7 degrees that would only give me about 3.75" of rise. that seems like a very little amount when looking at diffusers on other cars.
any thoughts?? would a dual plane diffuser work, like one on top of another
i want to make one out of fiberglass to fit my car, with the wizdom bumper i bought. i have been reading online. what i see is that the magic number is 7 degrees of incline off your refference point (flatbottom of the car) . i want to make this thing go from the diff up to the bumper, i havent measured but off the top of my head its like 2ft in distance, at 7 degrees that would only give me about 3.75" of rise. that seems like a very little amount when looking at diffusers on other cars.
any thoughts?? would a dual plane diffuser work, like one on top of another
#3
i think your right rev. if i remember correctly, the range is 3*- 7* of range. mine is just over 5deg. if it's too steep the air separates from the diffuser making it much less, if at all, effective. if you want it to blend into the bumper, and it's up higher than you need the diffuser to be, you just make a smooth bend at the very end of the diffuser to meet up to the bumper. i actually cut out my bumper above the diffuser to release any trapped air. i've seen alot of other "pro" race cars like that also, so it must not affect the diffuser.
#11
see that's what I was talking about. the curve up is at the very end. the important part is from the lowest point you can see back to the diff area. that's the part getting measured. at the steep curve up the airflow has all but detached at that point. only problem I see is that the fins are very shallow at the important part at the very bottom. again, I'm not an aerodynamicist if that is a word, I'm just going off of what I have read about it. I don't know how much downforce my diffuser is making, but I can tell you one thing for certain, with it, my car is much more directionally stable. I don't have to make any steering corrections at highway speeds and above. regardless of head/crosswinds of 40-60mph gusts, the car will track absolutely straight. cool thing is sometimes in a big gust, the car will feel like it hits a wall of air, and I can actually feel the car get pushed down (I have a big splitter and wing also) but it will not move a single inch in any direction. I live on the gulf coast so I have driven in windy conditions a million times. not to mention I always drive to the track so ive put alot of miles on with full Aero.
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see that's what I was talking about. the curve up is at the very end. the important part is from the lowest point you can see back to the diff area. that's the part getting measured. at the steep curve up the airflow has all but detached at that point. only problem I see is that the fins are very shallow at the important part at the very bottom. again, I'm not an aerodynamicist if that is a word, I'm just going off of what I have read about it. I don't know how much downforce my diffuser is making, but I can tell you one thing for certain, with it, my car is much more directionally stable. I don't have to make any steering corrections at highway speeds and above. regardless of head/crosswinds of 40-60mph gusts, the car will track absolutely straight. cool thing is sometimes in a big gust, the car will feel like it hits a wall of air, and I can actually feel the car get pushed down (I have a big splitter and wing also) but it will not move a single inch in any direction. I live on the gulf coast so I have driven in windy conditions a million times. not to mention I always drive to the track so ive put alot of miles on with full Aero.
Spoolin, happen to have any pictures of yours?
#14
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so for materials im gonna make mine from black fiberglass. from fiberglast.com
using ther 2000/2060 epoxy resin. im gonna vacuum bag it as well. ill have to 1st make the plug, then the mold. this prob wont be for a little while but i will keep you guys posted. im gonna take a stab at a smaller composite project 1st, custom canards for my autokonexion bumper. badass like voltex style ones
using ther 2000/2060 epoxy resin. im gonna vacuum bag it as well. ill have to 1st make the plug, then the mold. this prob wont be for a little while but i will keep you guys posted. im gonna take a stab at a smaller composite project 1st, custom canards for my autokonexion bumper. badass like voltex style ones
#19
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I would imagine that the only way to make the diffuser really effective is if there is a sealed off volume under the car.
So... side skirts? Front wheels sealed off between splitter and skirts?
So... side skirts? Front wheels sealed off between splitter and skirts?