DIY P2R Throttle Body Spacer For Si

2012 Civic Si Sedan (FB6/K24Z7)
P2R Throttle Body Spacer (TBS) Review

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Not an actual dyno.
P2RTBS_vs_Stock_Lab1.jpg


Summary: Gained 1 whp. Lost 7 lbft of midrange torque.

22-75 mph 3rd Gear Pull Comparison (Time: first instance of 75 *VSS - Time: first instance of 22 VSS)
Stock: 8.548 sec
P2R TBS: 8.644 sec --> -96ms slower

Stock: 07/06/14, 12:30 AM, *IAT=86, fuel=7 bars
P2R TBS: 07/09/14, 12:05 AM, IAT=84, fuel=5 bars

The chart above was plotted from FlashPro datalog.

Same back road,
same starting point,
same cold start from home to back road,
same stock tune/calibration,
same 3rd gear datalog.

Notes:
  • I drive this car 5-6 times a week. First drive after installation felt the same. The only difference is the subtle whistle at lower rpm.
  • Wind (head/tail) could have been a factor. I should have noted the outside temperature for IAT comparison.
  • Data log showed NO Traction Control slips on either one.
  • I do two data logs per modification/change. The second set is similar.
  • I understand that there are skeptics about not using an actual dynamo-meter (aka dyno). However, I'm merely highlighting the difference in torque and resulting calculated horsepower.
  • I think that the slower elapsed time (ET) in 3rd gear pull bolsters the story depicted in the chart.
Questions:
  1. Does P2R TBS require a tune and/or complementary modification in order to see gain?
  2. What could have I done wrong assuming P2R wouldn't sell a product that has placebo effect?
About Me:
I'm new to Flashpro and engine tuning and therefore any insight, constructive criticism, suggestion etc will be well appreciated. I am eager to learn this craft.

*IAT: Intake Air Temperature
*VSS: Vehicle Speed Sensor (ground speed)
 
Hi,
You should not be hearing a whistle at low RPM with the spacer installed. If you are hearing a whistle you most likely do not have the 1/8" npt plug screwed in deep enough.
Also we have dynoed 15-20 12+ civic si's with our TB spacer and have seen HP increases from 3-4 hp every time without any loss of Tq in the mid range. Every dyno we have done at our facility was done with the car strapped on the dyno. And installing the spacer without removing the car from the dyno. So we have been able to dyno test very fair comparisons of before and after.
 
Hi P2R,

Whistle is gone after the initial drive out. The 1/8" npt plug sit's ~3mm shy of being flushed. I stopped trying to screw the npt plug in because the adjustable wrench started deforming it. In other words, I did what I could with what I have.

Since there is room to wiggle the throttle body when the four screws are loose, I wonder if it is possible to tighten everything in such a way that intake manifold, TBS, gasket and throttle body do NOT perfectly line up (flushed) on the inside?

Possible root cause:
  1. Installation issue.
  2. Measurement issue
    1. methodology: not apple-to-apple
    2. equipment accuracy
    3. equipment defect
Do you have a sample dyno chart from one of the cars that were tested? How about data logs from one of the runs so we can make the comparison?
 
Since the plug is made out of nylon, it will actually flex fairly easily. The best thing to do is squeeze the head of the plug with a big enough pliers to be able to turn it the last few turns that's needed to sit flush.

I will get some dyno charts listed soon. Don't expect this week though, as I'm heading out of town on Wednesday and our dyno computer where all the graphs are on is still in storage.

I do not have any data logs. I will be able to provide that sort of stuff now that we own a car, but all the dynos from before were done on customer cars.
 
I appreciate the support (P2R). Alright, I'll re-install and force the plug to sit flush.

Per RobSBP's suggestion, I tightened the bolts a bit more. Is there a torque specification since I'm concern of over tightening it?
 
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