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Can you vent hood pressure out of fender and other solutions for C5Z06
I am wondering what are the best solutions to vent hood pressure without cutting hood or replacing hood?
Has anyone successfully vented out of fenders?
I am assuming if there was an easy non invasive fix then GM would have implemented it. Time is on my side and I am wondering over the last 18 years has anyone come up with a solution to hood pressure
There is no path from the engine compartment to the fenders, so I see lots of cutting to make it happen. Why not get a used hood to cut holes in for vents? I did that so I didnt have to cut my low mileage original hood.
You can remove the seal at the base of the windshield and probably get a little benefit. I like Kubs idea though, just buy another hood to hack up, I've been watching Craigslist and facebook marketplace for a hood myself for this same reason.
So you don't want to cut your hood but you're willing to hack into your fenders? Seriously, the Trakspec T1 is a proven design and looks pretty good. If you're reluctant to chop into your original hood pick up a spare and have at it!
I know but I don’t want to put a mismatched hood on my beautiful car!! Lol odds are I am just going to have to leave it and keep car well under 150mph ….
I read about possibly removing hood seal at the back of the hood on another thread but another forum member said that it would mess up aero and the vent at the back of the hood isn’t the best location.
looking at hoods ready buckle up and fly off it looks like anything to would help
I am not looking to cut up fenders I just didn’t know if there was a way to duct it but that doesn’t sound like it’s possible. I am picking my car up next week so I don’t have any visual to reference
I plan to paint mine blue eventually, but I didnt find a hood until 2 weeks before my first event this year. I found a $150 hood on Facebook marketplace, $260 trackspec vent, $50 vinyl was a quick and easy way to vent my hood and not hurt the original until I can have the time to paint it (probably next off season). The hood color doesnt slow it down any, and I can live with it for now.
I plan to paint mine blue eventually, but I didnt find a hood until 2 weeks before my first event this year. I found a $150 hood on Facebook marketplace, $260 trackspec vent, $50 vinyl was a quick and easy way to vent my hood and not hurt the original until I can have the time to paint it (probably next off season). The hood color doesnt slow it down any, and I can live with it for now.
looks good! And you have a back up vette!! Lol I have commemorative edition and the stripes are what throws off the mismatched hood. I could get away with it if I was a solid color but I’m sure the purist would have a melt down if if removed the stripes or cut up the carbon hood lol not that I want to do either of those. My car is 90% street car and will see light track use and regular autocross. Clean, pretty, and originality with reversible mods is my goal for the car.
The best solution is to do like you and have two vettes lol it looks like you track both. I would have one for street one for track if I had it my way
There is an air path from the engine bay to the fender vents already. It's not a straight shot, due to some splash guards, but I'm pretty sure some air must follow that path already. Removing the splash guards might help a little but I'd be surprised if it made a measurable difference.
looks good! And you have a back up vette!! Lol I have commemorative edition and the stripes are what throws off the mismatched hood. I could get away with it if I was a solid color but I’m sure the purist would have a melt down if if removed the stripes or cut up the carbon hood lol not that I want to do either of those. My car is 90% street car and will see light track use and regular autocross. Clean, pretty, and originality with reversible mods is my goal for the car.
The best solution is to do like you and have two vettes lol it looks like you track both. I would have one for street one for track if I had it my way
I've seen several people in here add vents to the CE hood. Not many purists over here in the racing section. We just like going fast!
The "back up" car is actually my friends car. Its at my place for a transmission swap because he doesnt have enough room. I have driven it before I got mine or when mine is down, so I guess it still is a back up to me, even though I dont own it, hahaha!
Typically the area at the base of the windshield is a pressure area. See the millions of cars that use that area for inlet air for heat/AC. See the 1000s of Hi perf and/or race cars that use the area for feeding the engine intake. Exactly how far forward on the hood the pressure area goes is different for every vehicle but I wouldn't expect a lot of help by removing the hood seal there.
The base of C5 hood is a high pressure area. Not suitable to vent high pressure from engine compartment.There was a professional paper written years ago based on C5 wind tunnel tests that, in part, contended that wheel well venting through top of fenders as is seen on quite a few C5 race cars is unnecessary.
I had the chief engineer for the re-entry aerodynamics team for the NASA space shuttle program at my house a couple of times looking at a guitar during Covid. Frankly, prior to finding out who he was, he came off as a goofball. Upon finding out his background, I mentioned having issues with my C5 race car at speed, implying that I wished that he had access to the a fore mentioned C5 wind tunnel study, and could give me some suggestions.
He replied, "since it's just subsonic aerodynamics I could just look at the car and tell you quite a bit. I dealt almost exclusively in supersonic calculations."
I pulled the car out of the garage and without giving him details of the cars tendencies over 140mph, he just nailed it. Lesson learned about judging someone based on Birkenstock's with white tube socks.
After NASA he taught at Stanford,then UVA grad programs. His focus at UVA was adaptive medical devices for people with injuries/ disabilities. He let his grad students apply for most of the patents, wanting to inspire them to excel.
You can remove the seal at the base of the windshield and probably get a little benefit. I like Kubs idea though, just buy another hood to hack up, I've been watching Craigslist and facebook marketplace for a hood myself for this same reason.
No you wont. The base of the windshield is a high pressure area. Removing the seal will introduce air into the engine bay, which is what you dont want.
I am wondering what are the best solutions to vent hood pressure without cutting hood or replacing hood?
Has anyone successfully vented out of fenders?
I am assuming if there was an easy non invasive fix then GM would have implemented it. Time is on my side and I am wondering over the last 18 years has anyone come up with a solution to hood pressure
I do not want to cut or replace hood
Nope sorry. Only way to vent under hood pressure is with a vent on the hood lol
Anyone have any data on what kind of temp differences vents make? One central vent, all three..... ect. I have a custom oil cooler set up thats working great but my coolant temps get up there on hot FL summer track days. Been looking for a hood to cut into myself.
I too have a 2004 ZO6 CE and I don't want to mess up the factory carbon fiber hood. I'd never cut a hole in it.
But I could use a used hood painted in Lemans Blue and the hood stripes can be applied in some manner to the new hood.
Originally Posted by Pugfather
looks good! And you have a back up vette!! Lol I have commemorative edition and the stripes are what throws off the mismatched hood. I could get away with it if I was a solid color but I’m sure the purist would have a melt down if if removed the stripes or cut up the carbon hood lol not that I want to do either of those. My car is 90% street car and will see light track use and regular autocross. Clean, pretty, and originality with reversible mods is my goal for the car.
The best solution is to do like you and have two vettes lol it looks like you track both. I would have one for street one for track if I had it my way
Anyone have any data on what kind of temp differences vents make? One central vent, all three..... ect. I have a custom oil cooler set up thats working great but my coolant temps get up there on hot FL summer track days. Been looking for a hood to cut into myself.
My C5's peak oil temps went from 245 to 235 after installing a vented hood - see post 8 above.
The base of C5 hood is a high pressure area. Not suitable to vent high pressure from engine compartment.There was a professional paper written years ago based on C5 wind tunnel tests that, in part, contended that wheel well venting through top of fenders as is seen on quite a few C5 race cars is unnecessary.
I had the chief engineer for the re-entry aerodynamics team for the NASA space shuttle program at my house a couple of times looking at a guitar during Covid. Frankly, prior to finding out who he was, he came off as a goofball. Upon finding out his background, I mentioned having issues with my C5 race car at speed, implying that I wished that he had access to the a fore mentioned C5 wind tunnel study, and could give me some suggestions.
He replied, "since it's just subsonic aerodynamics I could just look at the car and tell you quite a bit. I dealt almost exclusively in supersonic calculations."
I pulled the car out of the garage and without giving him details of the cars tendencies over 140mph, he just nailed it. Lesson learned about judging someone based on Birkenstock's with white tube socks.
After NASA he taught at Stanford,then UVA grad programs. His focus at UVA was adaptive medical devices for people with injuries/ disabilities. He let his grad students apply for most of the patents, wanting to inspire them to excel.
When I bought this car (back in 2008?) the previous owner had removed the seal from the hood at the base of the windshield. I struggled with SEVERE overheating issues for my first few events with the car. The engine was consistently running ~230°+. Heat management was brutal, and I could barely run ~3 laps without having to come in to cool the car down.
One day I was fortunate enough to get some advice from an experienced racer who specialized in aerodynamics ........... he took a very quick look at the car and said "well there's your problem". He pointed out the missing seal at the back of the hood. Because it's a high-pressure zone, air is forced back into the engine bay, effectively stalling the air flow that should be coming in from the front.
So I sealed up the hood and my overheating problems disappeared ....... the engine would run ~180° no problems.
When I bought this car (back in 2008?) the previous owner had removed the seal from the hood at the base of the windshield. I struggled with SEVERE overheating issues for my first few events with the car. The engine was consistently running ~230°+. Heat management was brutal, and I could barely run ~3 laps without having to come in to cool the car down.
One day I was fortunate enough to get some advice from an experienced racer who specialized in aerodynamics ........... he took a very quick look at the car and said "well there's your problem". He pointed out the missing seal at the back of the hood. Because it's a high-pressure zone, air is forced back into the engine bay, effectively stalling the air flow that should be coming in from the front.
So I sealed up the hood and my overheating problems disappeared ....... the engine would run ~180° no problems.
I've always known this, and I've always preached this, but it wasn't until just not that it clicked my 4th gen doesn't have that seal either! And to think I've had this thing since 2013. Off to one of the spares to steal the seal.
More on topic though, there are little cap dealies under the car that are stapled on IIRC. If removed, those would open up a path to exhaust air out the factory vents. I could not quantify its effectiveness though. There are also little flappy doodles up on the fender itself that need removed to help open up that path but beware on the passenger's side it will expose the PCM more to the elements.
04-05-2022, 11:58 PM
Can you vent hood pressure out of fender and other solutions for C5Z06
And to think I've had this thing since 2013. Off to one of the spares to steal the seal.