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Discussion Starter · #1 · (Edited)
I know a few folks here have done the work to port match their P2R throttle body gaskets to the throttle body spacer and I was going to do the same but last night when I was installing mine for the second time (switched to red versus black) I lined everything up for a dry fit and also put a caliper to each one and pretty much came to the conclusion that there's nothing to gain by port matching the gaskets to the spacer.

The measurements were 2.360" at the throttle body, 2.522" at the throttle body gaskets, 2.617" at the throttle body spacer, 2.520" at the intake manifold. So you can see how it steps up in size going to the spacer and then down to the intake manifold which means the gaskets aren't obstructing any flow and are actually the identical to the ID of the intake manifold opening.

Here's two pics that illustrate the throttle body with spacer and gaskets. The bolts are just dropped in the holes to make alignment easier. I'd recommend centering the gaskets as best as possible when you install the TBS, torque appropriately, then call it a day.



 

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Discussion Starter · #4 ·
Idk. The yellow spots on it shows where the air with oil hit the edges.
If any surface of the plastic gasket is exposed, it will collect a thin film of oil and discolor. Doesn't matter if you made the gasket ID .100" larger than the TBS. My point is that if you make the gasket the same ID as the TBS then you've got a larger "step" going from the TB to the first gasket and again from the last gasket to the IM. Leaving it untrimmed does a better job of acting as a diffuser at the TB and a collector at the IM since your step is more gradual. Ideally you could bevel the inside edge of the gaskets to perfectally transition from the small ID to the large and vice versa but at some point you're really splitting hairs (we may already be at that point). My point is that you're not helping at all spending your time trying to port match the gaskets to the spacer. Spend the energy somewhere else, like replacing the stinkin' intake air bypass control thermal valve that you break removing the hose to adjust the upper tube on your CAI! (I did that last night....grrrrrrrr!!! :banghead: ) or working a little longer to cover the $80 that it's costing me to have a new one shipped to my house.
 

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Discussion Starter · #10 ·
Finally found my little sticky note with the measurements I took (thought it was lost and wasn't going to pull everything apart to do it again). All measurements were the average of two measurements taken 90-degrees apart. I arranged the measurements to flow from intake to intake manifold.

2.439" Throttle Body, Intake Side
2.360" Throttle Body, Intake Manifold Side
2.522" Throttle Body Gasket
2.617" Throttle Body Spacer
2.522" Throttle Body Gasket
2.520" Intake Manifold
 

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Discussion Starter · #13 ·
:wavey: How much torque do you recommend?

Thanks :thumb: ,

Off the top of my head it was 14 lb*ft but I don't remember for sure. Definitely more than 10 and less than 20 just based on the size of the bolts and the materials. I will have to check the factory service manual next time it's within my reach but with the plastic gaskets I'd recommend torquing them again after a few good drives just to make sure there's no settling.
 
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