thats right ,, mirror finish for the exhaust and beaded for the intake,, i will prolly spend another 3 hours getting this slicker than glass.
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What gasoline? The injectors are way down the ports on an intake manifold.
You want some roughness on the walls. To put it simply... the air slowed by the rough texture acts as a "lubricant", promoting greater flow.
I believed the same thing that you guys are saying... until I spoke to someone that knows more than I do. Then I verified that info with someone that knows more than him. Then I looked into it myself to further verify the claim. You WANT some roughness. Trust me. Not a lot, but some. A mirror finish is bad.
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Hmmm. I'll have to do more research. Every porting thing I've ever read says to polish the exhaust, leave the intake smooth. Also, I do believe gasoline also hits the inside walls of the cylinder head near the valve, deev.
That are is often ported/polished.
Originally posted by sweet91accordComment
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"polished" doesn't mean mirror finish.
Perhaps I'm wrong about the exhaust side, as my information WAS regarding the intake... but the reasons for it were due to airflow properties, which should apply to exhaust as well as intake.
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every book i own mentions getting the exhaust side as smooth and bend free as possible, thus mendral bends and open cats and what not,,
the smoother the finish for the exhaust the better,
you want to get that air out quickly as possible,
the more texture the longer it takes,,
i could quote tons of stuff in these books,
but honestly i do not feel like typing that much.
for the intake side you are correct, but at the same note, on a turbo vehicle such as mine this doesn't make a hudge difference as it does on a N/A
so much air is being forced in ,, it's like a huricane and the air is just going everywhere without rough walls,, thus needing to get back out as quickly as possible, before heat soak begins to take effect.
although heat is good if contained in the exhaust port of the turbo,, allowing for shorter spool up time and more power.. but only if contained.
my problem with the 16 g was.. it had boost creep as well,, their design in general gives this,, the way to remove the boost creep is to port a hella lot out on the exhaust side of the manifold, and smoothing it best as possible so the exhaust can escape faster, and to allow the wastegate to open further.
because the wastegate must be large enough to bypass sufficient exhaust to prevent boost creep.
Boost creep occurs when the wastegate cannot bypass quite enough exhaust to prevent the boost pressure from rising about a preset or target boost pressure,
particularly if the compressor is oversized and normally running at lower end of it's performance envelope at maximum normal boost.
Once creep starts, it can run away with accelerating pressure rise as the initial boost increase feeds back into more exhaust, more boost, more engine rpm, more exhaust, more boost more rpm and so on- particularly on an engine with efficient exhaust and intake gas flow.
With the onset of creep, an oversized compressor may accelerate into a more efficient region of it's operating envelope, that is capable of totally overwhelming the wastegate and pushing boost to extreme levels.
although texture walls would create a higher torque due to backpressure it will also cause heat soak in that general area spreading like wildfire. since i have prorted mine, i will be getting a turbo jacket, or also known as heat wrap.
to keep as much energy as possible within the turbo for shorter lag time.Last edited by KeeleDesign; 03-15-2008, 11:53 AM."Self Renewed"Comment
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for clarification, I didnt have the shop do it, I bought it from a guy who owns a shop that did. I paid 475 shipped, but it was+ 600 new2010 Taurus SHO - Livernois Goodies
2002 BMW 330 CI Convertible - HUNK OF JUNKComment
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what a lil more elbo grease can accomplish..
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very nice work man2010 Taurus SHO - Livernois Goodies
2002 BMW 330 CI Convertible - HUNK OF JUNKComment
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well i have decided to go 6bolt when replacing the motor..
and for those of you who think a h22 swap is hard ,, well it's not and this swap is going to be alot more dificult. but i will get it done."Self Renewed"Comment
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somehow i wouldn't doubt that, even if you took all the mans money and tools he'd still end up with it done and done well.Originally posted by KeelesKustome
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crazzy the 6 bolt is 7:5:1 compression.. vs 7bolt 8:1
6 bolt has 60mm Tb ..vs 7 bolt has like a 54mm
i will be interchanging alot of parts for the best performance, i have alot of reading to do.
I will be purchasing the balance shaft elimintor kit as well.
along with a stage one type camshaft.
I have finished the porting on all the turbo,, my camera died and i just went ahead and put it back together.
i am contimplating on rather to go ahead and buy the shift kit for the tranny as well, and go ahead and paint my wheels black.. we will see."Self Renewed"Comment
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got curious tonight and pulled the head off to see the damage, and guess what the head was unscaved.. the head is in perfect condition,, we went over everything with a fine tooth comb. so thats awsome. i'll get pics of the block once we remove it."Self Renewed"Comment
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so you gonna use it and just get another block? or sell it to get some $ to help pay for everything?Originally posted by KeelesKustomeComment
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not sure at the moment..
the more reasearch i do shows how well the 2g head is designed, especially for lower rpm's vs the 1 g huge port high rpm.
my power band is low and i want it to stay that way being an auto.. so i am going to try and get a complete short block from the 1g and then have a machine shop bore the holes in my head to fit the 1g block, and resurface my head and make sure no valves are bent. if they are i will be replacing with new stainless and dual valve spring with retainers.
I would like to find some 1g cams to throw in here as well, but that is hard to do at the moment.
I will also be getting a 1g throttle body.
one great part about keeping my head, is that i still have the cam sensor on this head, so i don't have to go and do all kinds of mumbojumbo bull crap wiring. i will also be using the 1g rods that are alot stronger but the 2g pistons that are a higher compression. fully balanced."Self Renewed"Comment
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