Any one notice an increase in boost with an addition of a test pipe?

According to my Mitsubishi MR gauges I installed:
-I put on a cat-back exhaust no change.
-Next intake filter .1 at redline
-Added a test pipe and got .3 redline increase and .1 to .2 spike increase

Basically stock i was spiking 1.4 holding 0.9 at redline (bars or what ever measurements MR gauge reads) Now I'm spiking a tad over 1.5 and holding around 1.3ish .

The power increase up top in the RPM range is quite amazing. I didnt really notice anything from a filter and/or cat-back. But the testpipe really woke things up top and the higher rpm range increase in pull is very noticeable.

Oh and I'm running on the stock factory tune only. Only mods on the car are whats listed in my sig and t-bolt clamps on all the piping.

 

yea bro, same here I put my tp back on yesterday from a HFC cuz I am getting a tune from ams soon. I looked at my gauge while hitting it in 2nd it spikes to over 1.5 bar. I was amazed. I get fuel cut tho in 4th it seems like =\ thats why I am getting my walbro installed and a tune.

 

yea u will see a little higher spike with it. I know i did in my 8

 

Yep that and holding more boost till redline as well.

I'm just surprised no one really mentioned an increase in boost in the past threads. (or at least I didnt notice it) People mostly mentioned full boost coming sooner.

 

i didnt notice it with my catback and testpipe setup... but when i put my 3 inch DP on it spike a whole psi

 

I'm surprised that you're running a higher boost level, but the higher spike doesn't surprise me. You reduced the backpressure allowing the turbo to spool faster and the stock boost control system can't compensate fast enough, so it's spiking higher.

 

i went from stock exhaust to open dp and got 3psi more boost

 

Wow, so there is that much difference between a HFC and the test pipe... I almost regret my decision to go with the HFC then!

 

If the duty cycles are all still the same for the stock boost control solenoid, getting rid of the cat reduces backpressure between the cat and exhaust port. Wastegates are very simple mechanisms. So the spring pre-load at the WG actuator is the same, but the exhaust mani pressure to open it has dropped at the same boost pressure. So once the boost goes up high enough to match the old ex mani pressure then it will open.

Anytime you lower backpressure to the wastegate, the boost will always go up. Given you have the same spring and duty cycle, etc.

 

It's simple physics really. If you increase the ability to flow; it'll flow better!

Once you're tuned to fully optimize the changes, a stg 1 type Evo won't see a big difference from a HFC to a Test Pipe. Now go with a high octane tune or go to a bigger turbo and the gains get farther apart.

 

Synapse got it right.

Flowing better as you say will decrease PSI in simple physics terms, because PSI comes from restriction.

 

i know when i put on my FMIC with full pipe setup i boosted to like 30 almost. i had my MBC setup but with some restrictions so with more free flowing area more boost could pass through. just had to lower my MBC is all

 

Yep I have the same thing happen