Quote:
Originally Posted by Sven7
If you're seeing 18% aero improvement you should be seeing about 9% MPG improvement, or about 3-4mpg. Does this coincide?
I'm a bit concerned that the sides are too drastically tapered. Have you tuft tested the Kammback to know for sure that it's working?
Anyway congrats on the improvements  |
Sides can be too large angle indeed, angle of those is around 15 degrees, what I could measure, top is around 10 degrees, +/- 2 degrees easily to both because inaccuracy with measuring.
Fuel consumption is bit hard to know as I drive so little nowdays, full tank might last rest of the year if nothing special will happen.
But when I did drove 104km and around 30km of those with Kamm, I got already 10% better mileage than excepted, but even I fill slowly and so that fuel stays at ring level in filler neck, that can be easily just error as amount is so small.
Earlier experience however shows that this new Kamm is better than old Kamm and then together with grill block, rear wheel well fairings and front air dam, I could easily get 4l/100km level consumption and even lower, where as my standard level without mods is 5l/100km for summer conditions, that is 20% reduction if I'm not mistaken with my percentages (does happen and often).
So at the moment, there is no knowing, my car has no electronic brain so can't even get any kind of fuel consumption computer, injectors etc all mechanical.
Tuft testing is bit impossible as there are no one to film tufts, so that is making it bit hard to really know how well it does work.
That pic before painting is not really giving correct picture from angles, here is new photo from rear, still came out quite horrible, somehow it is such shape that is difficult to take good photo. Lower edge of support 'wing' I did turned too much in, but rest is not quite so horrible angled I think? It is not quite uniform currently and there are lot of bends to many direction, I plan to cure those with braces that I will put there, but to get that done needs of course that main shape is working, which I need to test more to really verify that.
In case you wonder, sticker reads "Reading a tuning magazine turns you into a f****** idiot".
I wanted to get top to curve down to around 10 degrees smoothly, but it is not quite easy to bend metal sheet way I like to, not with my poor skills at least and without any proper tools for such, so it is bit straight, but with speeds of 50Mph or less it probably is not so critical. It is better than without Kamm, it is better than old version, but perhaps not best that it can be.