Trackspec vents vs Varis vented hood?
 

I'm curious if there is any actual track data comparing which hood does the best job of cooling and reducing lift? I'm guessing no but thought it might be worth bringing up.

We've done A/B testing on both setups along with a few other vented hoods during a few 86CUP days. We've also tested the Trackspec vented hood setup against OEM hood at WSIR as a 3rd party tester with pressure transducers.

http://trackspecmotorsports.com/shop...ood-louver-kit

Some GT86 drivers we've supported in some of the hotter parts of the world. Popular vented hood setup vs. Trackspec vents vs. OEM hood.

https://www.counterspacegarage.com/b...its-data-2017/

TL;DR - works better than advertised. Come out to your local 86CUP event to check out the hood vents.

Trackspec > Verus

I'm talking about a Varis vented hood not verus/velox vents on a stock hood. Kind of confusing I know. Anyway I have a Varis vented hood with naca duct on order and I have friends with Trackspec vents so maybe we can do some kind of comparison.

http://www.ft86club.com/forums/showthread.php?t=119879

A vented hood (as opposed to a hood with vents installed after) will always look better. A lot more expensive though

Trackspec vents are a bit more efficient than Varis. We have ordered several Varis vented carbon hoods for clients in the past and they look pretty sweet. In terms of looks, Varis carbon hood is nice. In terms of pure function, Trackspec is more efficient.

Hey Mike, I have a couple questions:
1. The Trackspec website says, " We saw an average of a 43% reduction in underhood pressure (lift) over the area of the hood." Can you quantify that some other way? Maybe in pounds or something? 43% is an impressive figure, for sure. But if that is 43% of five pounds, it's not very meaningful in terms of lift reduction. I certainly expect it to be more than that, but it is worth asking.
2. I'm surprised there are no wickers on the Trackspec vents. I expect this is a deliberate design decision as opposed to something simply overlooked. What can you tell us about this?

Either is fine.
Trackspeck allows u to keep ur hood,
stock hood is lighter than most CF hoods as well,
cost effective
functional
low maintainence
rigid
proven.
If u gunna have a varis kit than the hood will go well with it.

Kinda makes you wonder if that was intentional... ;)

The Varis hood is great, but the TS vents are more functional due to their sheer surface area, assuming proper placement.

Note that the Varis hood and recommended TS placement are virtually identical.

1. Remember that pressure and weight are two completely different units of measurement. Pressure over an area can be measured as weight, but pressure alone cannot. There is no weight measurement because the measurement changes with speed, and industry standard for downforce is at 150mph, which is not a realistic speed for most 86's. However, using published figures, this extrapolates to about 65lbs of **net** lift reduction via the hood alone at 150mph. Different simulations show different results, but when you also factor in the reduction in air being expelled under the car, net lift reduction on the entire car at 150mph ranges from 120 to 200lbs at 150mph.

1a the best litmust test is the complete elimination of hood flap at highway speeds.

2. the first vent is effectively the wicker, but in this case, we are releasing pressure, not sucking air out, so a wicker would still not have a meaningful effect. On a different application, the wicker may be much more important.

How is the first vent effectively a wicker? There is no vertical element in front of it creating a low-pressure zone.
Yes, pressure is being released. But wouldn't sucking the air out be even more effective?
A reduction of 120 pounds to 200 pounds at 150 MPH is a LOT. I'm really surprised at those numbers. Very impressive.
I found a good article explaining the basics of some of this here.

the first tilted element performs the same basic function as a wicker; tuft testing shows there is no reversion in front of that first vent.

Sucking air out would in theory work better, but really only affects the front-most part of the flow. Pressure differentials are what create the airflow, and is similar to the engine fans doing little to nothing at speed in most cars to cool the radiator. The contribution of the fan, or wicker in this case, is negligible compared to the rest of the system.

It's like blowing into the wind in a hurricane; you'll have a little bit of flow change locally, but as a system, no real net effect on how the wind is blowing around you and where the air is flowing.

This isn't a cost saving measure either; from a manufacturing standpoint, it is only one extra bend and 2 extra tiny cuts. The manufacturing is already automated.

I'm really trying to keep my car as stock looking as possible. From the rear you wouldn't know it was modified. From the front that's becoming more difficult but I figure a painted Varis hood will stand out less than the Trackspec vents.

Other than that I will literally burn my hand on my stock hood with Velox vents. I went with the FRP hood with naca duct from Varis because I'm painting it anyway and was told it would still be lighter than the stock hood. Also really like that the Varis hoods come with a reinforced hood latch so additional aero latches aren't necessary.

I know I've heard that the Trackspec vents are actually suppose to increase the rigidity of the hood but that has not been my observation. Last time I saw one on a buddy's car and it was propped up, a moderate breeze was causing the hood to flex and looked like it wanted fly away like a kite. Lets just say it wasn't confidence inspiring that the vents improve the structure of the stock hood.

If you take a stock hood and lift up and down then compare with a hood with Trackspec vents, it's actually far less flimsy. The floppiness you observed is at the mount. If you're looking for reasons to go to the Trackspec vents, then it's overwhelmingly more performance oriented than other vented setups especially for the price. Enough so that it was originally banned in a few racing series for being too effective. :)

I think it's different things that are acting on the hood to make it seem more or less rigid.

Propped up, there is less structure of the hood to keep it's shape. But that's offset force from a passenger prop, gravity, etc.

BUT in place, the advantage of the (frankly enormous) trackspec vents is that there is SO much pass-through area that even though the structure of the hood is somewhat weakened by cutting it up and installing the vents, there is SO much less surface area of the hood to catch air and make it flop/wave in the wind that it actually appears stronger when driving.

ZERO experimentation - just something I noticed with a friend's car with the trackspec vents. It does feel floppier in the hand but seems to barely even get hit with air/wind under movement. Doesn't mean it's stronger, but the result is that it's less effected by the wind.