Improving aerodynamics (of '87 Nissan Bluebird)

[landspeed]

I'm thinking of full underbelly as one of the easier ways to improve drag,
without sacrificing appearance. I may also try at least partial rear wheel
skirts. Wing mirror cameras are a possibility, but also expensive.

Do you think a set of vortex generators across the roof would help at
all, without doing the full kamm wing etc?

Or... How about something like this? (see picture) - surely that would negate the
effect of the rear window angle (although the drag due to the size of the rear wake
would still be as large).

[The Toecutter]

Do you think a set of vortex generators across the roof would help at
all

From all of the data I've seen, not at all.

How about something like this? (see picture) - surely that would negate the
effect of the rear window angle (although the drag due to the size of the rear wake
would still be as large).

Looks like it would. Try making a mock-up and experimenting.

[MetroMPG]

Originally Posted by The Toecutter

From all of the data I've seen, not at all.

Can you point to some data?

[MetroMPG]

I think you'd be better off with something like this:





Try to get as much taper as possible (top & sides) approaching 10-12 degrees before you cut it off. Reduces wake size.

[landspeed]

Originally Posted by MetroMPG

I think you'd be better off with something like this:





Try to get as much taper as possible (top & sides) approaching 10-12 degrees before you cut it off. Reduces wake size.

I like the look of that - might try it soon!. Just need to find some coroplast, or whatever they call it in the UK, then try some SuperMID tests!. I will post back when I manage to get a mockup ready!.

On another note, fitted my EBH today (it is a 3kw circulating one - 'Kenlowe Hotstart') as shown here: http://www.kenlowe.com/pre-heaters/cars/diy.html
I'm really pleased with it, and tried it out for the first time this morning (my car was covered in ice). Will try it again tomorrow before going to work!.

Toecutter : I am also thinking of a grille block - my plan is to get a grille from the scrapyard, completely block it (because air can flow through some other gaps anyway), and use it in the winter, until it gets to hot to be useful. I also have my eyes on an aluminium rad from a Primera (G20 Altima), at the same scrapyard - smaller, lighter, better heat dissipation, and it means I can block a certain amount of the lower grille too!. Also, as it is smaller, it contains less coolant, making it lighter still in use.

[MetroMPG]

Good stuff. FYI, the results are likely to be small - I'd predict a 1-3% FE improvement @ 55 mph based on doing something similar to my car: http://www.metrompg.com/posts/boat-tail-prototype.htm

Not trying to discourage you. Go for it.

Thanks for the EBH link.

[MetroMPG]

Wow - that's a massively powerful EBH! Only 20 minutes plug-in recommended. Some good info on that site.

[landspeed]

I bought it on ebay, and the guy tried to rip me off - when I plugged it in, the water boiled within 10 seconds (it has a cup-sized amount of water inside). I removed it, took it apart, and it turns out the motor was seized solid. Using some oil, a mole wrench, and plenty of time, I managed to unseize it, and it now works perfectly - but the person selling it must have thought it was broken!. I like it so much, that I'm going to get one for my mums car as well!.

I think the aero mods are worth it, as the cumulative fuel saving could be quite good!. Also, given how bad the aero is on my car (the lower engine bay is just open to the road, it has that rear angle for the hatchback), I might get bigger savings!.

I want aluminium for the under-body stuff (at least for the engine bay) so need to find a source for that. However, I have found out that, in the UK, 'Coroplast' is called 'Correx', and is pretty cheap, so a partial kamm-back prototype might not be that far off!.

I'm now off to make that Circuit that Yoshi told me to do (for SuperMID!)

[MetroMPG]

It actually has a pump in it. Nice.

I mistakenly assumed it was convective (didn't read the site closely).

[MetroMPG]

(NOTE: moved the airtabs discussion to the VG thread:

http://www.gassavers.org/showthread.php?t=995)