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Discussion Starter · #1 ·
Can someone tell me what exactly these modifications mean? Also, how do these processes increase power? This IS more of a general question, but at the same time, are these practical modifications to our cars? Thanks for the lesson.
 

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If I understand corectly its expanding the size of the cylinder by shaving away part of the inside to increase compression.
I think it has miniumal gains on our cars, def not worth the price.
people have done it themselves with a dremel, so its not hard, but time consuming and warrenty voiding are two main factors.
 

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Re: (chromecarz00)

Boring is when you increase the diameter of the cylinder walls. Which requires upgrading the size of your pistons and rings if bored out to a larger size. Most bore out to .5mm incriments.

Porting is when you increase the size of the ports in the head. This is done to increase overall flow to make more power. When done its most common to polish the walls of the ports as well to reduce turbulance.
 

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Re: (chromecarz00)

Quote, originally posted by chromecarz00 »
If I understand corectly its expanding the size of the cylinder by shaving away part of the inside to increase compression.
I think it has miniumal gains on our cars, def not worth the price.
people have done it themselves with a dremel, so its not hard, but time consuming and warrenty voiding are two main factors.

It's also idiotic.

When porting and polishing a head you want to use a flow bench, and make sure you actually increase flow. You also want to ensure that your intake and exhaust aren't inhibiting your airflow, or making your head flow better can be useless. This is something that should be done by an experienced machine shop who will measure airflow before and after to ensure that he's not just hacking away for nothing.
 

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Re: (mofolicious)

Quote, originally posted by mofolicious »


It's also idiotic.

When porting and polishing a head you want to use a flow bench, and make sure you actually increase flow. You also want to ensure that your intake and exhaust aren't inhibiting your airflow, or making your head flow better can be useless. This is something that should be done by an experienced machine shop who will measure airflow before and after to ensure that he's not just hacking away for nothing.


Are we talking about doing it yourself or the conecpt of boring?
 

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Re: (chromecarz00)

Doing it yourself, or going to a machine shop that isn't equipped for testing to ensure what they are doing is going to be beneficial.

I've had it done on a different car. It sure looked pretty, and I'd like to think that it made a positive difference, but it could have been the cams I had installed at the time. Or maybe it wouldn't have been noticeable with the stock intake manifold if I hadn't upgraded. I had a new manifold with slightly larger ports and I had them match that. For all I know it could have been detrimental...
 

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Re: (mofolicious)

Agreed, for our cars porting and polishing the head is almost to no benefit unless required i.e. you increased the flow capacity of your exhaust and intake manifolds. We are fabricating my own intake manifold in order to get rid of the upper plastic plenum but still see no benefit to porting unless cams are in the mix.
 
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