good BIM/Polish cost?
02-25-2003, 06:45 AM
#1
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good BIM/Polish cost?
To get my IM bored to 58mm, it will cost me a case a beer which is like $15 here. 
Now to get it polished after they bore it, another case of beer.
Does anyone know what the IM on a 97 tiburon is made from, aluminum or steel? Also, how hard is it to take the IM out?
Now to get it polished after they bore it, another case of beer.
Does anyone know what the IM on a 97 tiburon is made from, aluminum or steel? Also, how hard is it to take the IM out?
02-25-2003, 07:48 AM
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As per Random
QUOTE
There's 2 opposing schools of thought on that.
One says that the last 4"-6" intake manifold should stay rough for air turbulence to promote air/fuel mixture.
In general, it has more to do with Throttle body injection engines and carbureted engines, not Port injection engines.
The other says that smooth intake manifold walls promote better air flow, increasing hp.
In our specific application(beta's and Alpha's), with the fuel injectors less than 3" away from the intake valves, and the fuel injecotors aimed RIGHT AT the intake valves, the better air flow (smooth intake manifold walls) is better than rough.
Rough intake manifold walls will not help air/fuel mixture since the air/fuel don't meet until well after the IM is over and the air is in the actual port itself. At which point turbulence is created by dividing the airflow into 2 ports, and forcing the air around the valves and into the combustion chambers.
It's a valid theory, when applied to the proper technology/engine style
If you wanna read this post go to PORT AND POLISH.
One says that the last 4"-6" intake manifold should stay rough for air turbulence to promote air/fuel mixture.
In general, it has more to do with Throttle body injection engines and carbureted engines, not Port injection engines.
The other says that smooth intake manifold walls promote better air flow, increasing hp.
In our specific application(beta's and Alpha's), with the fuel injectors less than 3" away from the intake valves, and the fuel injecotors aimed RIGHT AT the intake valves, the better air flow (smooth intake manifold walls) is better than rough.
Rough intake manifold walls will not help air/fuel mixture since the air/fuel don't meet until well after the IM is over and the air is in the actual port itself. At which point turbulence is created by dividing the airflow into 2 ports, and forcing the air around the valves and into the combustion chambers.
It's a valid theory, when applied to the proper technology/engine style
02-25-2003, 08:10 AM
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Oh! and to answer your question, In my opinion nothing is to hard. A pain in the *** maybe but not that hard. First remove all intake parts (stock air box or CAI)then your T/B linkage,it's trouble some, open up the throttle by hand and it should help you to get it off. there are two lines that go in to the TB, those are coolant/antifreeze lines, pull them off. You have to take off your fuel rail and injectors. Becareful, the injectors have clips, don't loose them. Remove the four nuts that hold the TB You have I believe are nine nuts that hold the IM to the block, Then you have a bracket underneath it with three 19 head bolts, if i'm not mistaken and might have to actually remove that bracket, can't recall. That should be about it. It takes me maybe about an hour and a half to remove. good luck.
02-25-2003, 08:26 AM
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I disagree,
the velocity of the air can be affected regardless
of wether fuel is present or not.
air is asmuch a fluid as fuel is.
Theres a large number of formulae for calculating
how the roughness can affect the velocity, not to
mention the atomisation.
a rough pipe can be turbulent at one flow rate, and
completely laminar at another.
pipe size also has a factor in the size of the
roughness.
If you're keen to find out what the real effect might be,
do research on 'Laminar flow and boundary layer',
then fork out for some R&D.
i'm just an unejumicated scumbag
tongue.gif
the velocity of the air can be affected regardless
of wether fuel is present or not.
air is asmuch a fluid as fuel is.
Theres a large number of formulae for calculating
how the roughness can affect the velocity, not to
mention the atomisation.
a rough pipe can be turbulent at one flow rate, and
completely laminar at another.
pipe size also has a factor in the size of the
roughness.
If you're keen to find out what the real effect might be,
do research on 'Laminar flow and boundary layer',
then fork out for some R&D.
i'm just an unejumicated scumbag
tongue.gif
02-25-2003, 09:52 AM
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all well and good, BUT
more to it, like I said, if you want to research
the real effect, its gunna take some brains and
some R&D.
QUOTE
A boundary layer usually changes from laminar to turbulent, due to disturbances in the viscous layer (Tollmien-Schlichting waves) that amplify. Amplification, though, occurs only if certain stability criteria (depending on Reynolds number, free-stream turbulence, surface conditions, forced vibrations, etc.) are not satisfied.
Your quote is the basics of the theory, but there is muchmore to it, like I said, if you want to research
the real effect, its gunna take some brains and
some R&D.