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Old 11-15-2008, 02:42 PM   #1
javastiwagon24
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Default Differance Between 04-06 and 07 STI Heads

I've got a guy who wants to trade me for a set of 07 Sti Heads with a Mild port and polish and Skunk2 spring/retainer set for my 04 Sti heads that are stock..
he needs them because there is a c shaped bracket near the drivers side cam sensor that is built into the cast... He wouldn't be running the avcs and my heads that are on the car obviously don't use that bracket because of the avcs...
So what are the major Differences between the 07 and the 04 sti heads. I have heard alot of bad things about the valves in the 07 and mostly good things about the 04 heads... \
I have also heard that the 07 has a bit more flow...

? is, is this a good road to go down. The heads he will be trading only have 1000 miles or so..
I understand that the 07's have the air pump but it already has the blocking plates...

Any info you guys could give me would be fantastic.
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Old 11-15-2008, 03:44 PM   #2
ASU
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What turbo you running ? Its important the head flows with the turbo .
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Old 11-15-2008, 04:14 PM   #3
javastiwagon24
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??????????????????????
Valves.... Are they good...In 07 besides not being sodium filled... Whats all this ring land cracking= bad valves.. ++shouldn't matter too much about the ringlands, have cosworth race bearings and weisco custom pistons 2618 HCompression.. the motor runs with somewhere between 8.9-9.2 ....
any other mechanical differences
What is the flow...Compared to 04-06sti
Will I have problem with tuning / fitment
Turbo is irrelevant don't have the money for bigger turbo now
fact of the matter is do the 07 flow more..
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Old 11-15-2008, 04:16 PM   #4
javastiwagon24
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?- 1 stay with my 04 heads.. 50k miles...
?- 2 Go with the 07s with free apr headstuds,mild port and polish and skunk2 springs and retainers. That have 30k miles but only 850miles on rebuild with fresh everything
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Old 11-15-2008, 04:45 PM   #5
gabedude
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The 07 heads are only different in the casting (air pump crap), coolant passages, and exhaust valves (not sodium filled). They do not flow more (valves are same size, comb chamber same, pistons, etc). The mapping on the 07 STi just reports higher G/S numbers, not voltage. The 07 STi is faster because of taller gearing in the 1/4 is all.
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Old 11-15-2008, 07:29 PM   #6
zeropsi
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Quote:
Originally Posted by javastiwagon24 View Post
??????????????????????
Valves.... Are they good...In 07 besides not being sodium filled... Whats all this ring land cracking= bad valves.. ++shouldn't matter too much about the ringlands, have cosworth race bearings and weisco custom pistons 2618 HCompression.. the motor runs with somewhere between 8.9-9.2 ....
any other mechanical differences
What is the flow...Compared to 04-06sti
Will I have problem with tuning / fitment
Turbo is irrelevant don't have the money for bigger turbo now
fact of the matter is do the 07 flow more..
What?! It has nothing to do with the valves...it's all to do with the A/F ratios, knock, and detonation. The factory tune leans them out, which is usually the start of the problem. The valves have nothing to do with it.
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