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Another incomplete project, these panels are hopefully going on the radical stroker. Not the mini stroker. There is another 2 vents to be made for the guards. All the vents preform a different function, that is relieving air pressure from different areas. E.G the rear vent on the guard at the top will vent engine bay pressure and heat as will the main bonnet/hood vent but that vent is targeting the cooling system.
I know the above looks like crap but it can be finished off nice, all of this takes lots of time I seem to be short of.
Greg -- The hood vent looks awesome. Do you think that'll fit with stock oil filler neck and cross brace?
‘I’ll take any compliment I can get! I’m pretty sure it does fit, I can check tomorrow because I designed that hood for my dry sump engine that was going to have the oil tank attached to the front of the engine like an F1 engine has a front mounted tank. I think the issue with it is the air filter and how that needs to be done. From memory and I have been working on numerous projects, I was going to fit a custom GM radiator with a standard GM Behr fan setup which is lower and that allows for the air pathway to the intake to be over the top of the radiator like many aftermarket cold air induction systems. It is also the way they do the intake system on the V8 Supercars here. However in saying all that I think there still is room for the factory setup. It’s just that I needed to improve the factory setup. Again I can confirm tomorrow when I refresh my memory.
What vent at the "top" if that is a vent?, it will be under high pressure if you are talking near the windshield and flow will enter the engine bay , not exit. (except for at a stop light ) the main vent in middle of the hood is a great design and will smooth flow exiting the vent, as fed by the radiator and main nose inlet. it really wont enhance cooling, as the radiator has an exit which is under the car, and is pretty effective at speed. that vent, will mainly help with downforce with a side benefit of cooling being its lower pressure on top than on the bottom of the car in that region.
the wheel well vents are common now on all race cars to vent high pressure air to the lower pressure region over the fender.
as far as location , you can see i made the vent at the best lowest pressure zones but it does extend further forward to near the seam of the hood bumper area if you need to do that. However, with the radiator in stock location, you wouldnt want to go that far forward obvoiusly. and yes, he stock intake inlets above the radiator work very well at sourcing high pressure cool air as an inlet souse.
Originally Posted by slate blue
Another incomplete project, these panels are hopefully going on the radical stroker. Not the mini stroker. There is another 2 vents to be made for the guards. All the vents preform a different function, that is relieving air pressure from different areas. E.G the rear vent on the guard at the top will vent engine bay pressure and heat as will the main bonnet/hood vent but that vent is targeting the cooling system.
I know the above looks like crap but it can be finished off nice, all of this takes lots of time I seem to be short of.
I've tried a lot of different things to get cool air into the SC. The original Murf kit took air in through a filter in the front fender, but since I have my intercooler heat exchangers there, it meant I had to think of another location. I now take in air through the front air inlets for the radiator. I built an air intake scoop that takes in air over the radiator and feeds it into an airbox that Tim and Todd built for me (http://928.jorj7.com/intake/ ). I've tested this on the dyno, and it results in as much rwhp as with the hood open and the air scoop removed. So for me that's good enough given my limited resources (time, money, and fabrication skills).
As for front air inlets for the intercooler heat exchangers and outlets for the heat from them and the engine compartment. I have inlets into each front fender under the fog/driving lights and the original sidemarker locations:
and oulets inside the wheel wells and on the tops of each fender plus three on the hood:
__________________
George
90 S4 Grand Prix White (Murf #5 - 210 mph top speed)
94 GTS 5-Speed Midnight Blue
06 Cayenne S Havanna/Sand Beige (PASM) http://928.jorj7.com
Originally Posted by davek9
Looked through a boat load of the Hood Mod threads, and chose this one to reopen, and it already had an Air Flow chart
I've bee looking at ways to get cooler fresh air to the SC or a stock Intake system for that matter by modifying an easily removal-able and replaceable part (like the hood).
Has anyone tried cutting off the front lip of the hood (about 1") leaving the latch and that support structure in-place, then opening up the underside structure and creating a cavity and venting it to the area where the stock Air intakes are.
The "look" i'm going for would be somewhat like one would find on a newer 911, pulling Air into the front edge of the hood.
Looking at newer performance cars with "cold air" intakes, most of them utilize some sort of scoop to an under hood cavity and the air box connects w/ that, leaving all the channeling on the bottom of the hood.
Thoughts on this, would it work?
Thanks,
Dave K
Edit: don't think this would increase any down force, could help w/ cooling, other better titled threads were closed
A follow on note, I have thought about drilling 1/2" holes through both sides of the front support bracket of the hood to allow more air into the air scoop, but with my current set up I haven't had a cool air restriction into the air box.
Also, these mods along with water injections and mist were done for cooling not down force.
__________________
George
90 S4 Grand Prix White (Murf #5 - 210 mph top speed)
94 GTS 5-Speed Midnight Blue
06 Cayenne S Havanna/Sand Beige (PASM) http://928.jorj7.com
Originally Posted by davek9
Looked through a boat load of the Hood Mod threads, and chose this one to reopen, and it already had an Air Flow chart
I've bee looking at ways to get cooler fresh air to the SC or a stock Intake system for that matter by modifying an easily removal-able and replaceable part (like the hood).
Has anyone tried cutting off the front lip of the hood (about 1") leaving the latch and that support structure in-place, then opening up the underside structure and creating a cavity and venting it to the area where the stock Air intakes are.
The "look" i'm going for would be somewhat like one would find on a newer 911, pulling Air into the front edge of the hood.
Looking at newer performance cars with "cold air" intakes, most of them utilize some sort of scoop to an under hood cavity and the air box connects w/ that, leaving all the channeling on the bottom of the hood.
Thoughts on this, would it work?
Thanks,
Dave K
Edit: don't think this would increase any down force, could help w/ cooling, other better titled threads were closed
Porsche 968 Turbos have NACA duct flowing air into the engine compartment at speed to cool the components around the exhaust manifolds. Do people think that this passenger side NACA duct is also just a cosmetic addition?
Again, you missed the points entirely. the naca duct will always draw air in via the dfferential pressure it makes AS LONG as the pressure on the intended flow side isnt higher than the side feeding the NACA duct. so you make a completey unrealed comparison. side flow NACA vents, for which i have usd on the race car, work . this is because there is a near pressure equalibrium to start. a NACA duct , on the hood in a low pressure zone will not create flow into the engine compartment, and certainly wont have a flow anywhere near the mass flow as what normally comes through the radiator and flow over the exhaust manifolds. the picture of the 968 turbo is not a factory mod and we dont have the pressure charts for this car to know what the pressure levels are at those two points. you cant be that gullible about some of the things that are bolted on to cars? do you see the engine layout of the 968 turbo? the exhaust manifold is UNDER The head in this picture on the left, yet the "NACA" ducts are pointing over the top of the heads and the intake manifold . so, if it was designed for exhaust manifold cooling, they are a little off the location mark. this is aftermarket, RS design that you have pictured. plenty of times, body mods are useless.
Originally Posted by ptuomov
Porsche 968 Turbos have NACA duct flowing air into the engine compartment at speed to cool the components around the exhaust manifolds. Do people think that this passenger side NACA duct is also just a cosmetic addition?
Last edited by mark kibort; 08-27-2018 at 01:15 PM.
So much wrongness there, Mark. Like I once jokingly said to sales guy working from home, "if you have to start day drinking in the AM because you can't stand watching your impossible four-year-old misbehaving, maybe give the liquor cabinet keys to the kid..."
That's not a 968 Turbo engine bay you chose to post there. The factory 968 turbos had 2-valve heads. The 968 Turbo had two NACA ducts from the factory, one feeding the air intake and another cooling the components around the exhaust manifold by pushing air into the engine compartment. The 968 Turbo RS had in addition an intercooler vent thru the hood.
I propose that you'll mitigate your ongoing embarrassment and further edit the errors out of that post.
Here is a trusted name in porsche race car manufacturing , KELLY MOSS . they built this one. these vents are used for a source of the intercooler, but it has FANs to flow air knowing that the pressure on the top of the hood is lower, so fans are needed to make a differential pressure.
.
Originally Posted by ptuomov
Porsche 968 Turbos have NACA duct flowing air into the engine compartment at speed to cool the components around the exhaust manifolds. Do people think that this passenger side NACA duct is also just a cosmetic addition?
I understand. i just used the picture to show what is on top of the engine near where those vents would point. i also added a 968 turbo below made by kelly moss. again, that area of the hood is likely a lower pressure zone. sure, they are limited with inlet area issues, so they need an opening. the only way to over come some of the pressure differential issues is to use a naca duct. it helps with the problem, and the problem is that is a bad location for inlet IF you can avoid it.. make sense??
Originally Posted by ptuomov
So much wrongness there, Mark. Like I once jokingly said to sales guy working from home, "if you have to start day drinking in the AM because you can't stand watching your impossible four-year-old misbehaving, maybe give the liquor cabinet keys to the kid..."
That's not a 968 Turbo engine bay you chose to post there. The factory 968 turbos had 2-valve heads. The 968 Turbo had two NACA ducts from the factory, one feeding the air intake and another cooling the components around the exhaust manifold by pushing air into the engine compartment. The 968 Turbo RS had in addition an intercooler vent thru the hood.
I propose that you'll mitigate your ongoing embarrassment and further edit the errors out of that post.
proof is in the location of the intercooler vent air exit. why are you fighing this. ( i posted the picture you linked below) i understand the purpose of your message, but you are missign the point. proof is IN your post of the 968 turbo. the vent is for the intercooler. why? because that is a known lower pressure zone to vent too from the intercooler , fed by ram air of the nose area. the naca ducts are not functional at at speed, because of this .unless the engine compartment is lower pressure than the top of the hood, those tiny naca ducts will not flow much. and more than likely will be vents . certainly there will not be a flow pattern to the exhaust manifold which is middl of the engine and down low..
tell you what .. ill get you some pressure measurements of my car at 120mph under the hood and over the hood... and ill even mock up a ram scoop to see if i can create any frontal pressure which is greater than under hood pressure.
Originally Posted by ptuomov
So much wrongness there, Mark. Like I once jokingly said to sales guy working from home, "if you have to start day drinking in the AM because you can't stand watching your impossible four-year-old misbehaving, maybe give the liquor cabinet keys to the kid..."
That's not a 968 Turbo engine bay you chose to post there. The factory 968 turbos had 2-valve heads. The 968 Turbo had two NACA ducts from the factory, one feeding the air intake and another cooling the components around the exhaust manifold by pushing air into the engine compartment. The 968 Turbo RS had in addition an intercooler vent thru the hood.
I propose that you'll mitigate your ongoing embarrassment and further edit the errors out of that post.