more intake pictures
#16
Thread Starter
Campeck Rulez
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Joined: Sep 2003
Posts: 6,102
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From: Woodstock, GA
well if you read my earlier post I am using power tools
I'm just having trouble getting into all the nooks and crannies.
My dad is gonna see if he can get a flexible extension so i can stick a bristle wheel into the arms and improve airflow.
I'm just having trouble getting into all the nooks and crannies.
My dad is gonna see if he can get a flexible extension so i can stick a bristle wheel into the arms and improve airflow.
#17
if you mess with the inside of the manifold it will decrease airflow. smooth is not always better necessarily... porsche designed it that way for a reason. do it if you want, but it's pretty retarded to mess with it. if you were to try that i'd go with some type of flexible hone, but also think about all the shavings you'll be making in there, not something i'd want going into my engine...
-Michael-
-Michael-
#18
Thread Starter
Campeck Rulez
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Joined: Sep 2003
Posts: 6,102
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From: Woodstock, GA
well lets see..............
you know all the litlle bumps that are in there?
look on the outside.
THATS whats inside
and no.....porsche did not design the intake to be all bumpy
we talked to a welder at a shop that handles porsche parts and he told us that early porsche and bmw castings sucked
as you can see
and how can it being smooth NOT help???
why do you think they smooth it out when the polish/powder coat/ or coat it with anything else?
not to be mean...............
still friends????
you know all the litlle bumps that are in there?
look on the outside.
THATS whats inside
and no.....porsche did not design the intake to be all bumpy
we talked to a welder at a shop that handles porsche parts and he told us that early porsche and bmw castings sucked
as you can see
and how can it being smooth NOT help???
why do you think they smooth it out when the polish/powder coat/ or coat it with anything else?
not to be mean...............
still friends????
#19
smoothed runners would absolutely help
I have a box of these things from Standard Abrasives, they're called cross-buffs. Actually, two boxes - a medium and a fine grit. If you put those on a flexible extension you can get the runners to shine. It's just a cheap alternative because there's no where near me that extrude hones.
I have a box of these things from Standard Abrasives, they're called cross-buffs. Actually, two boxes - a medium and a fine grit. If you put those on a flexible extension you can get the runners to shine. It's just a cheap alternative because there's no where near me that extrude hones.
#21
Originally posted by Travis - sflraver
I used a flexible butterfly to make the inside of my intake look like the outside of yours. Performance over looks any day in my book.
I used a flexible butterfly to make the inside of my intake look like the outside of yours. Performance over looks any day in my book.
But seriously where can one get something online to try this?
#25
take an aerodynamics class or two, ashton... my, it's nice to see a 15 year old knows more about airflow characteristics than an aviation student.
just because they smooth it to powder coat (on the OUTSIDE) doesnt mean it helps airflow, its the only way they could get to all the surface to make the paint/powder stick to the surface properly.
fyi, turbulent airflow has much better surface adherence than does smooth airflow(hence vortex generators on aircraft), so by making the boundary layer of the interior of the intake turbulent, its helping the rest of the airflow maintain velocity. that adhesion helps to reduce drag inside of the intake, and makes the air flow faster into the engine.
so, your WELDER 'handles' porsche parts, thats fantastic. now, does he design things based on aerodynamic principles? i know for a fact Porsche does, and heck they even did at the time of making our cars too.
also, the only way i could think of extrude honing as helping airflow would be to make bigger intake runners, and increase volume. i'm not sure how that would help, as the intake needs velocity, and air at certain resonant frequencies to operate efficiently. if you make it bigger and the engine is still set up to use a smaller intake runner, you're going to affect the engine operation, most likely in a negative way. perhaps small, but negative nonetheless.
perhaps you should do a little research before you haul off and bother to polish out the inside of that intake.
-Michael-
just because they smooth it to powder coat (on the OUTSIDE) doesnt mean it helps airflow, its the only way they could get to all the surface to make the paint/powder stick to the surface properly.
fyi, turbulent airflow has much better surface adherence than does smooth airflow(hence vortex generators on aircraft), so by making the boundary layer of the interior of the intake turbulent, its helping the rest of the airflow maintain velocity. that adhesion helps to reduce drag inside of the intake, and makes the air flow faster into the engine.
so, your WELDER 'handles' porsche parts, thats fantastic. now, does he design things based on aerodynamic principles? i know for a fact Porsche does, and heck they even did at the time of making our cars too.
also, the only way i could think of extrude honing as helping airflow would be to make bigger intake runners, and increase volume. i'm not sure how that would help, as the intake needs velocity, and air at certain resonant frequencies to operate efficiently. if you make it bigger and the engine is still set up to use a smaller intake runner, you're going to affect the engine operation, most likely in a negative way. perhaps small, but negative nonetheless.
perhaps you should do a little research before you haul off and bother to polish out the inside of that intake.
-Michael-
#26
EDIT Michael beat me to it and pretty much said it better, but I'll leave my post up too
Polishing the intake runners is not really all that beneficial when you compare the cost in man hours to the added (or lost) power. What Michael was trying to point out is that if you polish the hell out of the intake runners (inside) and actually hog out a lot of material you can actually decrease the intake velocity, thereby decreasing power. Most of the stuff I've read, and the "experts" I've talked to, about doing head work for instance, will tell you that you really just want to improve the flow path. You don't want to do anything to decrease compression (we're still talking about my head work example) or screw up port velocity. They ALL say that internal polishing is a waste of time (smooth is good, polished is a waste). You have to remember that the imperfections in the runners are pretty small/low and will likely sit well within the boundary layer without affecting flow too much.
Regarding tools, you need to think about a die grinder with a cone buff and some cutting compound, NOT polishing compound. It will get into the tight places better than that wheel or sand paper. And wear a good mask, that stuff is really bad for you lungs. Also, the castings are really porous, and like everyone had already said, will dull over time. Keep the polished bits wiped down (Boeshield) and you should be OK. I polished off the PORSCHE on my cam tower three years ago and haven't really done much too it since and it still looks pretty shiney.
Don't polish cast wheels. At least without clear coating afterward.
Polishing the intake runners is not really all that beneficial when you compare the cost in man hours to the added (or lost) power. What Michael was trying to point out is that if you polish the hell out of the intake runners (inside) and actually hog out a lot of material you can actually decrease the intake velocity, thereby decreasing power. Most of the stuff I've read, and the "experts" I've talked to, about doing head work for instance, will tell you that you really just want to improve the flow path. You don't want to do anything to decrease compression (we're still talking about my head work example) or screw up port velocity. They ALL say that internal polishing is a waste of time (smooth is good, polished is a waste). You have to remember that the imperfections in the runners are pretty small/low and will likely sit well within the boundary layer without affecting flow too much.
Regarding tools, you need to think about a die grinder with a cone buff and some cutting compound, NOT polishing compound. It will get into the tight places better than that wheel or sand paper. And wear a good mask, that stuff is really bad for you lungs. Also, the castings are really porous, and like everyone had already said, will dull over time. Keep the polished bits wiped down (Boeshield) and you should be OK. I polished off the PORSCHE on my cam tower three years ago and haven't really done much too it since and it still looks pretty shiney.
Don't polish cast wheels. At least without clear coating afterward.
Last edited by Manning; 11-25-2003 at 12:51 AM.
#28
hehe manning - i'd guess its due to being driven daily, all that heat probably keeps it from oxidizing too much, maybe this would work on the intake manifold too...
-Michael- 'yet another reason to drive the car... a lot'
-Michael- 'yet another reason to drive the car... a lot'
#30
I don't know as much about aerodynamics as I'd like, but I've always heard you NEVER want a completely smooth intake tract. The turbulence (I've heard) also helps atomize the fuel for more efficient combustion...hence more power than a non-turbulent system. Correct me if I'm wrong and explain why, I love the theories and numbers.