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Discussion Starter #1
May car has been in the following condition for over a year. I tried to get it tuned Saturday and it just would hold boost over 18psi. I plugged the intake track to a air compressor and found my problem.

Pic 1:
This is how the throttlebody is mounted to the intake manifold. Note that it is rotated.


Pic 2:
This is how the seal surface of the intake manifold looks. Notice that there is more surface to the left of the bolt pattern


Pic 3:
This is how the seal surface of the TB looks. Note the cutout and ports between the bottom two holes. These features are supposed to face the beforementioned extra seal surface of the intake manifold.


The way I had the TB mounted to the IM, the ports butted agains the gasket, but nothing was behind the gasket. I'm suprised that it sealed as good as it has for as long as it has. The intake track has been pressurized before without an obvious leak, but this time it was very audible. I fixed the leak with an extra gasket and an aluminum spacer.
 

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Discussion Starter #5
whitson01 said:
i dont see how this would be an advantage..??
Reversing my manifold reduced over 4 feet of intercooler hose. 4ft of 2.5" tube and .065 wall equates to 211 cubis inches of space that doesn't have to be pressurized. Pressure builds quicker. Is it quicker enough to notice the difference? Maybe not, but as a rule, the shorter you can make the path between the turbo and the throttle body, the better. Same goes for the engine heads and the turbo.

The only way I can do any comparison is to plot the boost chart of my car vs my buddy's. His car is similar, but uses an APS intercooler kit. Both cars have been get tuned at the same place by the same tuner. I can't get that information for at least another week.
 

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Discussion Starter #8
trnkmnky said:
Have I seen your car at precision tuning? The intake manifold looks familiar
I can't say that I've heard of Precision Tuning.
 

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Hilarious.......I just promised myself(while daydeaming about mods) that I will do this for the FMIC and make some custom piping.

Ya let us know....Lets see those boost data logs
 

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redrexx said:
Reversing my manifold reduced over 4 feet of intercooler hose. 4ft of 2.5" tube and .065 wall equates to 211 cubis inches of space that doesn't have to be pressurized. Pressure builds quicker. Is it quicker enough to notice the difference? Maybe not, but as a rule, the shorter you can make the path between the turbo and the throttle body, the better. Same goes for the engine heads and the turbo.

The only way I can do any comparison is to plot the boost chart of my car vs my buddy's. His car is similar, but uses an APS intercooler kit. Both cars have been get tuned at the same place by the same tuner. I can't get that information for at least another week.
Sharp answer. I personally feel the same. It's a worthwhile upgrade if you have pushed all of your other components to the limit. Every little bit counts.
 
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