2008 Honda Accord sedan aero improvements

[ar5boosted]

Originally Posted by Daschicken

Having experience grille blocking 2 different accords, i've got some info for you.

Previously I had a 2005 4 cylinder 5mt, I could block MOST of the bottom grille, but not entirely or it would start to overheat. I don't remember which temperatures were too hot for it. Never tried an upper grille block on that car.

With my current 2006 V6 6mt I usually run a 60-70% lower grille block. Above 85 degrees and the fan kicks on a lot. When it drops below 50 degrees I can run a partial upper grille block, usually blocking half of the upper grille.

If you are willing, I strongly recommend pulling off the front bumper and making a panel to ensure the incoming airflow going to the lower grille does not bypass the radiator by going underneath it. I did this and a partially ducted grille block and was able to make the opening smaller while keeping the same cooling capacity, if not better.

Sounds reasonable.

My old-school Turbo car has bonnet vents and bonnet scoop. Because of a Top-Mount-Intercooler it got to a point where it had significant cooling issues.



What I learnt from it is that reverse scoop bonnet vents are the-best*. Within that model Toyota found that out as well and the factory did actually change the design completely over to reverse-scoops.



There are various different types and will let air out away from the frontal area. Since hot air rises, it's easy to work out how they work.

Ordinarily on most passenger cars, they are designed on the premise that if airflow is fast enough, hot air will be pushed down and under the car and out the back. That's true, but hot air prefers to rise.

Anyway, I support blocking off the front in the way that others do and suggest the investigation of reverse-scoops to get back what you are losing.

Perhaps there is another way of dispensing the heat such as using black panels to disperse heat in stealth mode. In a way that would only show up on a thermal camera -

[ScottDR]

Thanks to aerohead I will be adding a rear lip spoiler. That's it so far unless I add some vortex generators at the rear roofline.

[Daschicken]

Originally Posted by ScottDR

Thanks to aerohead I will be adding a rear lip spoiler. That's it so far unless I add some vortex generators at the rear roofline.

Vortex generators are frequently discussed on here, and I have yet to see any improvements from cars. Trucks are another story, but cars are not designed like trucks. I have looked up vortex generators before and the people selling them claim all sorts of things they don't do, such as 'reduced wind noise'. No, they actually increase wind noise.

Don't waste your money on that. I mean, you can if you want, but I wouldn't. I would buy another 4' x 8' sheet or 2 of coroplast for vortex generator money.

See if the underside of your accord is anything similar to this:


If it is, then you could get the 7th gen hybrid rear diffuser, which looks like:


I got mine for $40.