4th gen rear diffuser - Honda Prelude Forum

luder7807 · 01-05-2011, 06:45 PM

i couldnt never find one for the 4th gen other than the one with holes in it so i had access to alot of carbon fiber and kevlar from a friend that works for a company that build monorails and planes so its taken a lot of time and thinking to imagine how the air would move well at first it was for look and fun but he told me they have a wind tunnel to test planes and monorails and i could bring my car and try it...so i found out that if you build it right it acctually is functionally and makes a difference we tried with and without it and there was a good noticable difference enough that it was worth it

luder7807 · 01-05-2011, 06:57 PM

also found out out factory spoilers have no effect for the car downforce wise and for full speed slows us down other than that 4th gens seem to have great downforce it actually registered near where some parts that they make for monorails achieved well im not sure how much that really means but he said thats pretty amazing for a car designed to go 140 we got to 195 mph winds before the car started lifting too much to be safe with the diffuser only 177 without it

petern101 · 01-05-2011, 08:09 PM

aerodynamics are awesome but there comes a point of diminishing value.

Lowering the car helps, covering up unnecessary holes helps, making a full underbody panel def. helps, but all this doesn't matter unless you are tracking the car or one of those hypermilers.

Reasons those two won't matter:

1. track car: helps but 4th gen preludes aren't competitive so the tenths of seconds doesn't matter

2. hypermiler: cost of all this not worth the miles / gas saved

To make a diffuser work properly also, the exhaust pipes get in the way. If you notice super cars with real rear diffusers, exhausts are in the middle or on the outsides. Also the car must be pretty low to create that area of high pressure. Not daily driving worthy (or a very expensive).