Cooling effect of Feed hood?
 

Hey guys, I need your help here. My husband and I are looking for an aftermarket hood for the FD. I want the Feed hood since it keeps the sexy stock look but my husband wants the Knight Sports hood for the cooling effects. I searched for some hard facts and stats of the cooling effects of the Feed without much luck. We have a PFS SMIC and we are going single turbo.

Does anyone have any cooling stats you could give me to help me convince my husband we should get the Feed hood over the knight Sports?

Please help me get the hood I want :)
Thanks

Which Feed hood and which KS hood?

Original or replicas?

Thanks for the link GreatShamanGT. I did see that thread while I was searching and it is good information. I was hoping to find some actual temp differences. Also, it looks like the air is flowing into the engine bay rather than releaing the hot air like a vented hood should. At least that is how I understand it to work.

And to Gracer7, we would be getting either a Shine Feed replica or a Seibon KS replica.

I would probably go with the KS because you have large vents right above the radiator area where air needs to escape. If you are doing street driving this would probably be better.

I doubt that you will find an actual temperature difference test with numbers.

From the wool test done on the FEED hood, it doesnt seem like much air is actually being drawn from the front of the car. If anything, I suspect most of the air being discharged from the first vent (furthest from window) is coming from the second vent (nearest). That thread seems to support the arguement for the KS hood :tonque:

I hope you are considering quality of fitment along with your decision. The Shine Feed hood had poor quality hood latch.

Here is a forum elder who uses a KS style replica hood sourced from Pettit
http://www.negative-camber.org/crispyrx7/hood.htm

I also like the look of the Shine Feed hood b/c it is less obtrusive. I know of more people tracking with the KS hood but it has been available a lot longer than the Feed style hood that Shine makes.

I don't think anyone has hard numbers on improvements from the hood. Some might have impressions.

if you are really looking for maximum cooling from hoods, most racecars actually have ducting underneath the hood to "guide" the hot air out. If your car is a street car, with single turbo, even driving aggressively for a long time (what's a long time on public streets...10mins??) you'll be fine wit either hood.

Style wise, I may be biase but I think Feed hood looks pretty sweet :)

Agreed. ^^^ Love the subtle look of the feed hood.

I'm not convinced a vented hood is 'needed' for cooling effects. There are many things that should be done first before considering a vented hood based on the supposed cooling benefits alone. Aesthetics are a different matter of course :)

on my FD I have went to great lengths to optimize the oil and cooling system and have never really felt the need for a vented hood, be it on the road race course or on the street. For a dedicated racecar maybe, but otherwise......

feed hood looks sexy, i definitely do not regret buying it, temperature wise, it is definitely better than stock hood if you are still running stock twins, at least for street driving

There's an argument, particularly for folks who track their cars, that there are two benefits from a vented hood:

1. Is "cooling" by giving air ingested at the front of the car and heated through heat exchangers, a low-resistance route out from under the hood. It also allows heat to escape when parked, theoretically reducing heat soak (which has a street application).

2. The second is (more for track guys) to reduce lift at the front at speed. Air being ingested low, and leaving over the car should reduce "float" at speed.

I personally have no cooling issues on track, even with twin turbos, and I could probably improve that further with a v-mount, but a vented hood should help too. I think that the only one that was ever (maybe) tunnel tested was the Mazdaspeed, and I can't confirm that—but it's clear that you need the vent towards the middle of the hood. The Mazdaspeed also has a bit of a "lip" at the leading edge of the vent, which presumable creates a low pressure area behind it for air to escape. The KS is probably a decent bet as well.

However, given my cooling stability, the aero benefit would be the only reason I'd seriously consider one because I've never liked the look much (the FEED is the best IMO).

I have the KS hood and I've noticed a huge cooling difference, plus it looks great and the fitment is really good

I see the need on a race car, for a street car it is near useless. A proper setup intake and IC(especially with water/meth) will keep intake temps down, correctly setup Oil coolers and radiator will keep coolant and oil temps in check.

However, the feed hood is sexier than Rich(goodfella) in a banana hammock, not that I would know :scratch::lol:

I disagree that it's "useless" for a street car. All the heat exchanger in the world will still heat soak. The vented hood will help when parked/sitting in traffic... similar to if you popped your hood.

the way i see it is, the OP cares for looks more. get the hood you like along with a good radiator, lower temp thermostat, hoses good oil coolers and i think you should be fine in terms of cooling

i have the feed hood and i love the looks of it.. i think the KS is too much

Water/meth will do a whole lot more for ridding heat soak then running no hood would ever accomplish. With most after market hoods you always have to worry about it raining, you have to run hood pins, often times the alignment is horrible. To most it isnt worth dealing with the extra headaches for the small gains that are seen in a street car. Once again, this is just my opinion, I also think V-mounts are over priced/over rated so take my opinion for what it is. ;)

I don't see this as a debate of the merits of one cooling enhancing mod vs. another. However, just because meth/water works well, or a big IC works well, cooling is a system, and a properly vented hood will help or enhance whatever else you have.

Vented hoods have their downsides, as you list, and among them are the reasons I don't have one myself—but to say it's "useless" is not accurate.

If we're going to debate shortcomings (and we don't need to), a vented hood is a non-mechanical part that will always work. Meth/water systems, by my observation, are additional mechanical complexity that can fail. Nobody ever blew their motor from a failed hood.

worrying about it raining couldn't be further from the truth. i have to go over my polished parts every time i wash the car. but the hood is more than worth it in traffic or city driving. And if you get a decent quality one the latch that comes with it can be almost on par with factory and alignment tends to be pretty good. again this is on a substantially well made hood. not the cheap ass $300 ebay stuff

echoing ptrhahns statements...

I recently did the KS hood from Pettit. I have seen about 5-10 deg F lower temps. I have all the other stuff like MS radiator, dual oil coolers and so on. I say that unless you are running 180 deg F at the track you can do better. The FD retards timing as temps rise so I believe this extra 10 deg really helps. It’s also great for street driving as things don't get cooked as badly. I can see the heat pouring out of the vents in traffic. If I didn't have a vented hood where would that heat go? Nowhere, that’s where.

That FEED hood doesn't look like it will do anything but look different. It looks like fish gills if you ask me, not a functional car part. Might as well have fake vents like a Mustang if you don't put the vents in the right place.

Here is a link to my hood project:

http://www.silverbulletrx7.com/Hood/index.html

Ditto.

I installed the KS hood yesterday and am seeing temps 10-15C cooler :)

thesaint

Thank you everyone for all your input. I am learning a lot from this thread.
What has been discussed and is the main concern for us is the heat soak. We live in Phoenix AZ and the temps in the summer are an absolute killer on the rotary engine.

We are planning on doing all the neccesary cooling mods such as W/M, the dual oil coolers and also single turbo. We are also going to try something else that we just found in the new 'Street Rotary' book that just came out, written by Mark Warner. My husband has done tons of research and has not come across this idea before. For those of you that have the book, it is on page 112. For those that do not, you will have to go to Amazon and get the book :wink:.

It sounds like I am going to lose this battle and we should get the KS hood.

Thanks again!

Best cooling mod is a V-mount IC + Radiator setup. Search on my old posts regarding performance and temp data. Relatively cheap and highly effective compared to a hood or single turbo setup.

I have a seibon KS bonnet.. it looks great and cools well but the fitment was shocking in my case. I had to file/drill out the mounting holes on the hinges quite a fair bit just so i could get enough movement in the bonnet to make it fit decently.

That said it now sits pretty good after quite a long time playing around with it.

My washer jets didn't fit too i must add, and i've read a few people with seibon bonnets couldn't use their oem washer jets. I just went to my local parts store and found some aftermarker black ones that screw in from underneath, fitted really nice.

:)