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A very bad example

 
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Blake
Been there, done that


Joined: 12 Jul 2005
Posts: 133
Location: Portland, OR

PostPosted: Mon Jan 30, 2006 9:21 pm    Post subject: A very bad example Reply with quote

Okay, some things are useful only by serving as a bad example. This is perhaps the perfect bad example. If rats could chew through metal, this is what it would look like. The poor guy I bought this engine core from paid someone $3,000 to port and rebuild the engine. I wish I could say this is very unusual, but the fact of the matter is that most "professional" porting is not much better, and the rest of the rebuilding work is similarly slipshod. Buyers beware!






I put squiggly marks where the port edges are extremely uneven and arrows where other attrocities have occured (like porting into the area where the oil seals ride). I will not bother explaining all the less obvious incompetencies. This is really, really, REALLY bad port work, as should be obvious to even a casual observer. It looks worse in person.
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Blake Qualley
Pineapple Racing, Inc.
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Blake
Been there, done that


Joined: 12 Jul 2005
Posts: 133
Location: Portland, OR

PostPosted: Mon Jan 30, 2006 9:54 pm    Post subject: Reply with quote

For contrast, this is what good porting looks like. Obviously, this example is of a bridge port, but the principle is the same...it should look clean and smooth, with nice transitions in cross-sectional area. Doesn't need to be this shiny, though. A little texture helps prevent fuel wetting.


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Blake Qualley
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Shrapnel



Joined: 20 Oct 2005
Posts: 19

PostPosted: Sat Feb 11, 2006 12:25 am    Post subject: Reply with quote

That workmanship is crap and the person who did it obviously has no pride in his work. However, a question - would rough porting like that adversely affect a car's performance, or will any old hole in the metal do the job?
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Tony Shrapnel
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Shrapnel



Joined: 20 Oct 2005
Posts: 19

PostPosted: Thu Mar 02, 2006 5:58 am    Post subject: Reply with quote

Yeah - I agree. But would it make any appreciable difference to the car's performance?
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sorrow



Joined: 02 Dec 2005
Posts: 5

PostPosted: Tue Mar 28, 2006 7:50 pm    Post subject: Reply with quote

Most likely a rough edge like that would tear up the seal as it rides past. Also the air flow is drasticly affected (at least in the heads ive worked on for other cars) It becomes too chaotic. It should never be underestimated the power that good ordered air flow will provide.

Looks like they used a hand approach with the wrong die.. or failed to follow up with polish because they knew they had allready pushed it out too far. In the first photo you can see tell tale signs of someone leaving the grinder on one spot too long.
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shahjohan



Joined: 15 Sep 2006
Posts: 3
Location: Kuala Lumpur, Malaysia

PostPosted: Fri Sep 15, 2006 3:17 am    Post subject: Reply with quote

my grandma work, more better from you.. for who did porting in bad porting picture..
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