To hood or scope
08-06-2004, 05:58 PM
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To hood or scope
I have a 83' 944 NA. After making the engine reliable, I am starting planning the fisical modifications.
I originally considered replacing the air intake for a cone filter till I realized I would be taking in the warm air from the radiator. That's when the brainstorm began.
First, How do you keep water from entering a hood scope and getting the filter wet?
Second, What is better, a scope to ram air into the intake or a vent to drain the warm air out?
PS. I am considering permanently replace the manual sunroof for a polycarbon vent. The manual sunroof is either on or of, no half way point.
I originally considered replacing the air intake for a cone filter till I realized I would be taking in the warm air from the radiator. That's when the brainstorm began.
First, How do you keep water from entering a hood scope and getting the filter wet?
Second, What is better, a scope to ram air into the intake or a vent to drain the warm air out?
PS. I am considering permanently replace the manual sunroof for a polycarbon vent. The manual sunroof is either on or of, no half way point.
08-09-2004, 03:46 AM
#2
Drifting
Good questions. Cone intakes offer a good gulp of air that bumps up HP, with a louder exhaust note. The downside to having them is that with the increased airflow...also you get increased microscopic particulate matter buildup in the engine combustion chamber. Not good- after so many miles. The engineers at Porsche already considered this- but decided to opt for conventional sources of induction....just to be safe. When developing the air filter for the 928- Porsche and Mahle figured that the stock 928 airbox dimensions is sized for a reasonably good gulp of air already. They knew the filtering elements would have to not restrict that charge in any way. That is why each OEM air filter is made with a 50% fibreglass weave, to trap microscopic particles by deionizing them. The filters actually cost more to produce than K&N's Filtercharger product- which is nothing more than five layers of surgical gauze, sandwiched between two formed layers of window mesh screening. If I were you...I'd stick with the OEM filter. They are high-quality, and designed specifically to protect your car.
If you still insist a cone is what you "need"....then try keeping the cone filter as far away from the hot engine as possible. I had an idea before to mount the cone filter inside the front fender, behind where the factory intake hole starts, directly forward of the coolant expansion tank. This will assure the charge air is always cold, from behind the fender. Run a steel tube along where the old airbox tube ran, and terminate straight into the airflow sensor, or better - MAF sensor. Water such as rain will not enter the fender at all. But, beware of those deep puddles! All it takes is one slurp of water and the engine is toast.
A scoop would be better than a vent- which is why race teams have them in the first place. We should follow their lead, by example. As for the sunroof- my personal favorite is the Saratoga glass top. But, it is rare and absurdly expensive. Take good care of that 83' NA motor.....my avatar is also an 83' motor, fully-rebuilt, polished, ported, knife-edged crank, internally balanced, and electroplated with forged KS pistons, 1987 head/cam/headers + DME sensors, 9lb flywheel, matched 928 injectors, and 3mm over-bored throttle. It gets on the chassis Dyno next week. I estimate 188hp...all normally-aspirated smoothness!
Zach
If you still insist a cone is what you "need"....then try keeping the cone filter as far away from the hot engine as possible. I had an idea before to mount the cone filter inside the front fender, behind where the factory intake hole starts, directly forward of the coolant expansion tank. This will assure the charge air is always cold, from behind the fender. Run a steel tube along where the old airbox tube ran, and terminate straight into the airflow sensor, or better - MAF sensor. Water such as rain will not enter the fender at all. But, beware of those deep puddles! All it takes is one slurp of water and the engine is toast.
A scoop would be better than a vent- which is why race teams have them in the first place. We should follow their lead, by example. As for the sunroof- my personal favorite is the Saratoga glass top. But, it is rare and absurdly expensive. Take good care of that 83' NA motor.....my avatar is also an 83' motor, fully-rebuilt, polished, ported, knife-edged crank, internally balanced, and electroplated with forged KS pistons, 1987 head/cam/headers + DME sensors, 9lb flywheel, matched 928 injectors, and 3mm over-bored throttle. It gets on the chassis Dyno next week. I estimate 188hp...all normally-aspirated smoothness!
Zach
08-09-2004, 09:44 AM
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Originally Posted by Dilberto
Good questions. Cone intakes offer a good gulp of air that bumps up HP, with a louder exhaust note. The downside to having them is that with the increased airflow...also you get increased microscopic particulate matter buildup in the engine combustion chamber. Not good- after so many miles. The engineers at Porsche already considered this- but decided to opt for conventional sources of induction....just to be safe. When developing the air filter for the 928- Porsche and Mahle figured that the stock 928 airbox dimensions is sized for a reasonably good gulp of air already. They knew the filtering elements would have to not restrict that charge in any way. That is why each OEM air filter is made with a 50% fibreglass weave, to trap microscopic particles by deionizing them. The filters actually cost more to produce than K&N's Filtercharger product- which is nothing more than five layers of surgical gauze, sandwiched between two formed layers of window mesh screening. If I were you...I'd stick with the OEM filter. They are high-quality, and designed specifically to protect your car.
If you still insist a cone is what you "need"....then try keeping the cone filter as far away from the hot engine as possible. I had an idea before to mount the cone filter inside the front fender, behind where the factory intake hole starts, directly forward of the coolant expansion tank. This will assure the charge air is always cold, from behind the fender. Run a steel tube along where the old airbox tube ran, and terminate straight into the airflow sensor, or better - MAF sensor. Water such as rain will not enter the fender at all. But, beware of those deep puddles! All it takes is one slurp of water and the engine is toast.
A scoop would be better than a vent- which is why race teams have them in the first place. We should follow their lead, by example. As for the sunroof- my personal favorite is the Saratoga glass top. But, it is rare and absurdly expensive. Take good care of that 83' NA motor.....my avatar is also an 83' motor, fully-rebuilt, polished, ported, knife-edged crank, internally balanced, and electroplated with forged KS pistons, 1987 head/cam/headers + DME sensors, 9lb flywheel, matched 928 injectors, and 3mm over-bored throttle. It gets on the chassis Dyno next week. I estimate 188hp...all normally-aspirated smoothness!
Zach
If you still insist a cone is what you "need"....then try keeping the cone filter as far away from the hot engine as possible. I had an idea before to mount the cone filter inside the front fender, behind where the factory intake hole starts, directly forward of the coolant expansion tank. This will assure the charge air is always cold, from behind the fender. Run a steel tube along where the old airbox tube ran, and terminate straight into the airflow sensor, or better - MAF sensor. Water such as rain will not enter the fender at all. But, beware of those deep puddles! All it takes is one slurp of water and the engine is toast.
A scoop would be better than a vent- which is why race teams have them in the first place. We should follow their lead, by example. As for the sunroof- my personal favorite is the Saratoga glass top. But, it is rare and absurdly expensive. Take good care of that 83' NA motor.....my avatar is also an 83' motor, fully-rebuilt, polished, ported, knife-edged crank, internally balanced, and electroplated with forged KS pistons, 1987 head/cam/headers + DME sensors, 9lb flywheel, matched 928 injectors, and 3mm over-bored throttle. It gets on the chassis Dyno next week. I estimate 188hp...all normally-aspirated smoothness!
Zach
while i don't have time to reply to this whole post...
let me start out by saying in the first sentence you are wrong, and wrong again. cone filters aren't where the hp increase is from. the increase would be from resonance tuning of the intake runner lengths and tubing lengths. the filter in our cars is HUGE, and it is NOT the point of restriction. the airflow sensor, however, is. the stig tested a cone filter versus stock setup on a dyno, and the results were minimal at best, but there was a sacrifice. porsche knew what they were doing when they put these badboys together.
the cone filter will do NOTHING for exhaust note, but it does provide a decent intake sound... now you can achieve this by drilling a few holes in your intake or by modifying your box top in several ways (i have a spare i've done this with and put it on on occassion when i feel like hearing my intake), but there really isn't a performance gain from it. many on here have done some research, a good idea would be to use the search and ferret out some info...
as for mimicing race cars - they have both scoops and vents. big vents for oil coolers and radiators - if you let the air in, you have to let it out somehow. aerodynamically speaking, you can create downforce by sucking air from under the car creating low pressure, and venting it elsewhere. the 996 TT has big vents in the rear fenders for oil/intercoolers. the hole in the top of the 911 engine cover is for letting air out, sucking cool air from UNDER the car, through the cylinders. vents are very useful, if you put them in the right place. scoops have their place, but i don't think that other than brake cooling ducts where the fog light used to be, any are needed.
p.s. i'm very interested to see your dyno results...
Last edited by ERAU-944; 08-09-2004 at 10:01 AM.
08-09-2004, 09:58 AM
#6
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Originally Posted by Dilberto
Good questions. Cone intakes offer a good gulp of air that bumps up HP, with a louder exhaust note. The downside to having them is that with the increased airflow...also you get increased microscopic particulate matter buildup in the engine combustion chamber. Not good- after so many miles. The engineers at Porsche already considered this- but decided to opt for conventional sources of induction....just to be safe. When developing the air filter for the 928- Porsche and Mahle figured that the stock 928 airbox dimensions is sized for a reasonably good gulp of air already. They knew the filtering elements would have to not restrict that charge in any way. That is why each OEM air filter is made with a 50% fibreglass weave, to trap microscopic particles by deionizing them. The filters actually cost more to produce than K&N's Filtercharger product- which is nothing more than five layers of surgical gauze, sandwiched between two formed layers of window mesh screening. If I were you...I'd stick with the OEM filter. They are high-quality, and designed specifically to protect your car.
If you still insist a cone is what you "need"....then try keeping the cone filter as far away from the hot engine as possible. I had an idea before to mount the cone filter inside the front fender, behind where the factory intake hole starts, directly forward of the coolant expansion tank. This will assure the charge air is always cold, from behind the fender. Run a steel tube along where the old airbox tube ran, and terminate straight into the airflow sensor, or better - MAF sensor. Water such as rain will not enter the fender at all. But, beware of those deep puddles! All it takes is one slurp of water and the engine is toast.
A scoop would be better than a vent- which is why race teams have them in the first place. We should follow their lead, by example. As for the sunroof- my personal favorite is the Saratoga glass top. But, it is rare and absurdly expensive. Take good care of that 83' NA motor.....my avatar is also an 83' motor, fully-rebuilt, polished, ported, knife-edged crank, internally balanced, and electroplated with forged KS pistons, 1987 head/cam/headers + DME sensors, 9lb flywheel, matched 928 injectors, and 3mm over-bored throttle. It gets on the chassis Dyno next week. I estimate 188hp...all normally-aspirated smoothness!
Zach
If you still insist a cone is what you "need"....then try keeping the cone filter as far away from the hot engine as possible. I had an idea before to mount the cone filter inside the front fender, behind where the factory intake hole starts, directly forward of the coolant expansion tank. This will assure the charge air is always cold, from behind the fender. Run a steel tube along where the old airbox tube ran, and terminate straight into the airflow sensor, or better - MAF sensor. Water such as rain will not enter the fender at all. But, beware of those deep puddles! All it takes is one slurp of water and the engine is toast.
A scoop would be better than a vent- which is why race teams have them in the first place. We should follow their lead, by example. As for the sunroof- my personal favorite is the Saratoga glass top. But, it is rare and absurdly expensive. Take good care of that 83' NA motor.....my avatar is also an 83' motor, fully-rebuilt, polished, ported, knife-edged crank, internally balanced, and electroplated with forged KS pistons, 1987 head/cam/headers + DME sensors, 9lb flywheel, matched 928 injectors, and 3mm over-bored throttle. It gets on the chassis Dyno next week. I estimate 188hp...all normally-aspirated smoothness!
Zach
08-09-2004, 01:57 PM
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Ok, these are the body modifications I have planned out.
1)NACA duct right over the air filter box, cutting out the filter box and making a seal around it between the hood and the box.
2) 1 or 2 vents behind the NACA duct, 1 above the header and 1 above the manifold.
3)Seal up the sunroof with a costum formed policarbon or plexiglass vent, as to vacum out the cabin (I plan to get rid of all the AC items so I need the extra ventilation.
4) Posibly a vent on the side, behind the front wheel, as to vent the front brakes.
What do you think?
1)NACA duct right over the air filter box, cutting out the filter box and making a seal around it between the hood and the box.
2) 1 or 2 vents behind the NACA duct, 1 above the header and 1 above the manifold.
3)Seal up the sunroof with a costum formed policarbon or plexiglass vent, as to vacum out the cabin (I plan to get rid of all the AC items so I need the extra ventilation.
4) Posibly a vent on the side, behind the front wheel, as to vent the front brakes.
What do you think?
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08-09-2004, 05:45 PM
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Now I'm all confuseded about what the doctor wanted to do to my knee. was he going to use a scope to scoop or .....
in the end will i be fisicaly fit or fiscally unfit or physically fit or unfit or.....
i hate fisical exercise or restraint
in the end will i be fisicaly fit or fiscally unfit or physically fit or unfit or.....
i hate fisical exercise or restraint
08-09-2004, 06:31 PM
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I think hes refering to a tank periscope on the hood, but a better spot would be in the roof. Find a REALLY tall one and we'd finally be able to see over all those stupid oversized SUVs!
08-10-2004, 09:56 AM
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well, technically, from a lot of simple grammatical/phonetical errors. i'd try to overlook it, as most guys here will razz you for just about anything, its all part of being one of the guys.
that said, people on the board here are mostly about functional mods. while the ones you have described would be functional to an extent, here's a couple reasons why you're getting razzed:
1. unless you're planning on hitting the track, and HARD HARD HARD with those brakes, there's no way you'll need vents or scoops to help cool them.
2. the cone filter business has been beat to death on this forum, and a little searching would yield all the answers you'd need
3. a lot of people like giving non-members a hard time (myself included on occasion), and sometimes not without good reason - specifically look at the first reply to this post. most of that is hogwash, so it would not really help you at all; we like to stick with the stuff that works around here, and most times it's exactly what or close to what porsche engineered. you can't get much better anything without spending a bunch of money or sacrificing something else on the car.
now, with that said, if you need a decent manual sunroof to use for a mold or anything, let me know, i have a couple sitting here at the house and i could send you one.
welcome to rennlist - welcome to the jungle
that said, people on the board here are mostly about functional mods. while the ones you have described would be functional to an extent, here's a couple reasons why you're getting razzed:
1. unless you're planning on hitting the track, and HARD HARD HARD with those brakes, there's no way you'll need vents or scoops to help cool them.
2. the cone filter business has been beat to death on this forum, and a little searching would yield all the answers you'd need
3. a lot of people like giving non-members a hard time (myself included on occasion), and sometimes not without good reason - specifically look at the first reply to this post. most of that is hogwash, so it would not really help you at all; we like to stick with the stuff that works around here, and most times it's exactly what or close to what porsche engineered. you can't get much better anything without spending a bunch of money or sacrificing something else on the car.
now, with that said, if you need a decent manual sunroof to use for a mold or anything, let me know, i have a couple sitting here at the house and i could send you one.
welcome to rennlist - welcome to the jungle
08-10-2004, 10:08 AM
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Originally Posted by Dalilean
Jeez.....
All this from a simple gramatical error?
All this from a simple gramatical error?
It was for some simple spelling errors!
