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Old 07-08-2003, 06:39 PM   #1
Daytona
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Default 3/8ths hose to boost regulator mod?

I read a few blurbs that were linked from unrelated threads about installing a larger hose to the boost controller and it helping the STi to build boost faster (14 lbs in 1st gear instead of 11)

Does anyone have some rather specific details on this conversion, like pics and how to make a bigger hose fit on the same small hole?
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Old 07-08-2003, 07:39 PM   #2
KoneKiller
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Default ok... that's pretty funny

From the 'bigger must be better" school of tuning?
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Old 07-09-2003, 12:28 PM   #3
Daytona
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Default What I read must have been a joke...

There were links to threads on this forum about up-sizing the hose going to the boost controller and how it 'improved response' etc. they cited boostmonkey as the source of the idea.

I had posted another thread inquiring about how I could source a resonator remover 'neck' that doesn't involve mangling my stock resonator, simply replacing it with a simple plastic duct.

Half of the responses to this were rather impish.

super-heated boost fluid?

blinker bearings?

one flatly told me that I dare not mod my car w/out doing more research.

It saddens me to see that because my post count isn't a zillion or that that I don't want to throw on a blitz sus just 'cuz it seems to be the cool thing to do, that makes me a noob idiot. I have been on other fine forums for about a year and have found the members to be quite professional and also adult. In the forum's defense, the thread was closed by the moderator.
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Old 07-09-2003, 03:04 PM   #4
KoneKiller
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Default Daytona

I think some of us are frustrated by the amount of fertilizer that is being spread out there. There are a lot of monkey's spouting off about how this or that improves the performance of this car or that car.

Most of it is BS and some of it is downright humorous. I think the 3/8 inch hose thing is one of the more idiotic things I've read since joining this forum.

It's hard to see a scientific rationale for that making an improvement. And, none of these 'tuners' have the test equipment to detect the difference if it existed.

I have had the good fortune to get to know a real serious race motor builder (LeMans, Daytona 24 hr... that sort of thing) and he makes a lot of money pulling Monkey-shines off of people's motors for them.

What these monkeytuners never come clean about is that their tricks gain some performance in one factor but usually give up some performance in two or three other factors. Any chimpanzee can get another 100 hp out of a motor, but it takes a real artist to get HP and torque and make it broad enough to be USEFUL and MEANINGFUL.

There is a nasty cult of "bigger is better" out there. Bigger turbo is better, bigger IC is better, bigger sway bar is better, bigger wheels are better, bigger brakes are better. None of these are true.

A bigger turbo may flow more air at the top end, but it has a heavier turbine and takes forever to spool up. Yes, you make more HP at 7000 RPM in a SLOW dyno acceleration test. But on the track, you make less boost down low and probably never see the benefit of that additional horsepower on the road. You THINK it's faster because it whines like a @#%^&% banshee. But the numbers show little or no speed improvement. If you ask someone who races a real turbo race car, they will tell you they use the smallest turbo they can.

Same with brakes. Big brakes slow the car faster, but they make the car slower because of the rotating mass. Real racers always use the smallest brakes that will DO THE JOB.

The factors that determine how much boost you develop in first gear have more to do with your right foot than any hose. And never forget, the sole solitary goal for first gear is to get to second gear without much wheelspin.

Enjoy your car
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Old 07-09-2003, 03:29 PM   #5
happasaiyan
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Default Re: What I read must have been a joke...

Quote:
Originally posted by Daytona
There were links to threads on this forum about up-sizing the hose going to the boost controller and how it 'improved response' etc. they cited boostmonkey as the source of the idea.

I had posted another thread inquiring about how I could source a resonator remover 'neck' that doesn't involve mangling my stock resonator, simply replacing it with a simple plastic duct.

Half of the responses to this were rather impish.

super-heated boost fluid?

blinker bearings?

one flatly told me that I dare not mod my car w/out doing more research.

It saddens me to see that because my post count isn't a zillion or that that I don't want to throw on a blitz sus just 'cuz it seems to be the cool thing to do, that makes me a noob idiot. I have been on other fine forums for about a year and have found the members to be quite professional and also adult. In the forum's defense, the thread was closed by the moderator.
yeah...welcome to nasioc.

i didnt want to join here till there were NO STi people on clubwrx. oh well...
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Old 07-09-2003, 03:32 PM   #6
inchoate
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Default

hay daytona, do a search in the FFI forum, you might find info at scoobymods as well. only one way to find out if it works. your engine is your own responsibility though.
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Old 07-09-2003, 08:31 PM   #7
mochanges
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Default Re: What I read must have been a joke...

Quote:
Originally posted by Daytona


Half of the responses to this were rather impish.

super-heated boost fluid?

blinker bearings?

one flatly told me that I dare not mod my car w/out doing more research.

Unfortunately, many people here have serious attitude problems. Everything is considered "rice", anything except for the "best" (in their opinion) is stupid and everything is ok to rip on. Respect is not something that many people here have. I rarely post and just read here, and post and ask questions on other boards.

Sorry to hear you have had the same experience.
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Old 07-09-2003, 09:13 PM   #8
offset
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Default

I hate to see that this topic has gone too far OT; but I will still throw my two cents in

FWIW this is one of the more adult forums on the internet all together. Several very intelligent (and at times very opinionated) folks do more than just lurk and flame like so many other forums. We do still get some punks and kids on here once in a while; and there is also the occasional 'off the deep end' response where someone who is normally rational goes too far in a response. But all in all, this is a good place.

offset

PS The responses to Daytona's question did seem a little harsher than normal. I was glad to see that thread stopped.

PSS It would be interesting to hear from one of the more mechanically inclined what a larger tube would do on the boost controller and why.
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Old 07-09-2003, 09:24 PM   #9
SkirtBoy
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Default

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Old 07-10-2003, 04:04 AM   #10
KoneKiller
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Default

It's just hard to see how this could make the 'improvements' these guys have noticed.

Placebo effect?
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Old 07-10-2003, 09:34 AM   #11
mazdman
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Default

I'll give my 2 cents on this subject. I own both a 94 RX-7 & a 95
Eclipse GSX along w/ the STI. I have modded both cars pretty heavily
& can tell you that both use orifices in the wastegate lines to control boost.

The GSX uses a bleed type system similar to the STI to bleed
pressure coming from the compressor housing away from the
wastegate actuator to keep it shut. This orifice creates a pressure
drop & therefore is able to bleed off only a certain amount of
pressure. By removing this orifice from the BCS, the system is
able to bleed more pressure & I effectively saw about a 2 psi
boost increase (verified by my boost gauge).

The RX-7 uses a different control system but still uses restrictors
in the wastegate lines as well and when I upgraded the intake.
exhaust, ECU, etc , I was getting peak boost of around 15-16 psi.
By enlarging this orifice by only about 0.005-0.010" (I'm going
from memory, it's been a while), it had a dramatic effect on
reducing the peak boost down to around 10-12 psi.

You can take this FWIW.
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Old 07-10-2003, 12:36 PM   #12
happasaiyan
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Default

Quote:
Originally posted by KoneKiller
It's just hard to see how this could make the 'improvements' these guys have noticed.

Placebo effect?
maybe you should get to know your car a little more before saying what will and will not work, and then attacking people for that.

i just dont understand what is wrong with some of the people on this board.
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Old 07-10-2003, 01:19 PM   #13
mochanges
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Default

Quote:
Originally posted by KoneKiller
It's just hard to see how this could make the 'improvements' these guys have noticed.

Placebo effect?
Now why is it so hard to write an intelligent response the first time instead of some smart ass remark that does nothing for anyone? The above is actually helpful as opposed to your first post, which only discourages people from posting. Doesn't that defeat the whole purpose of this board?

As far as improvements, it seems that several tuners have recommended against this (my brother spoke to God about it and he said not to do it), unfortunately I can't remember why. Maybe a few phone calls/emails are in order to get feedback from some knowledgable tuners.
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Old 07-10-2003, 02:44 PM   #14
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do not do the 3/16 mod it will only degrade your performance

the stock boost is a closed loop system the ecu
it expects the 1/8 restrictor
when the 3/16 is put in place the ecu has a proublem controlling the amount of boost the car makes ..
and becasue it can not control the boost it pulls timing thus degrading performance

this is the case for ANY form of boost control other than a reflash...
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Old 07-10-2003, 02:50 PM   #15
Daytona
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Default Wow, what a guy!

Jaxx strikes again! He answers all my questions with logic, knowledge and professionalism!

That answer completely makes sense and I truly appreciate this quandry being put to bed.

Anything from Vishnu on a reflash?
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Old 07-10-2003, 03:07 PM   #16
zacek
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I am not sure on that one Jaxx, assuming the 3/16" mod will give you a .5psi to .75.psi increase (not to mention the increased response) like it did on the WRX, how could such a small increase in pressure cause the ECU to pull timing? I guess the only problem with this would be at the current knocking range (4k-5k) but assuming this was not an issue the 3/16" mod should not degrade performance.

It would be interesting to see the results of this mod. on a STi that seems to knock in this range and one that does not.
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Old 07-10-2003, 03:58 PM   #17
Daytona
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Default The reason for 'timing pull' is not overboost

the stock boost is a closed loop system the ecu
it expects the 1/8 restrictor
when the 3/16 is put in place the ecu has a proublem controlling the amount of boost the car makes ..


This means that since the computer cannot control the boost like it expects to, it pulls timing. Timing is not pulled because the boost is abnormally high.
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Old 07-10-2003, 04:35 PM   #18
KoneKiller
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Default

OK.. I apologize for my first post. It was a bit flamey. And I'll gladly acknowledge that I have no expertise in the boost control system for this car.

So, at this point, we have two sets of experts who disagree over whether increasing the size of this coupler is good or bad.

Does dropping the pressure in that system open or close the wastegate?
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Old 07-10-2003, 07:51 PM   #19
peczenij
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Default TurboXS

A TurboXS Stage 2 uses an Auxilary Boost Controller in the location you are talking about. Rotating the Auxillary Boost
Controller allows you to increase boost. This allows the ECU to vary the boost in all gears per normal. The extra boost is complimented with extra fuel via a UTEC or UNICHIP...

Can the STI take more bost if it's detonating already?
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Old 07-10-2003, 08:18 PM   #20
KoneKiller
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Default Let me see if I can clarify my question...

Does increasing pressure in the hose leading to the actuator/wastegate controller (for lack of a better term... dashpot), cause the wastegate to open (reducing boost) or close (increasing boost)?
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Old 07-10-2003, 09:06 PM   #21
mochanges
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Kone, I have alot of respect for you for your post, seriously, that's cool of you.

I spoke with my brother who said that God told him this mod leads to boost spikes. That's all I know.

-Mohammad
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Old 07-11-2003, 08:48 AM   #22
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I think that's what he is talking about. The first picture in that thread is my engine. I don't run that mod any more, but if you have any questions just ask. In playing around with the boost system (as you say, it is a system), I have learned a lot about how it works, and how it causes the ECU to react. I have also learned that some of the most vocal people on this board don't know their ass from a hole in the ground.

It basically boils down to the fact that there are 2 types of gearheads here:

1. Those (probably old-school) types that go for ingenuity, and the self-gratification of doing/learning/tuning/building something themselves, and

2. Those that think anything other than handing their car + blank check to a "tuner" is just silly. Many of these are the overly vocal ones that let mommy and daddy hand over that blank check...

Of course their are exceptions to the rule (AZ, PDW, etc. etc.), it's just that many folk here like to post before they think.


VV

Quote:
Originally posted by robroy72
I think you guys are talking about this mod.
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Old 07-11-2003, 11:11 AM   #23
KoneKiller
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Default Re: Let me see if I can clarify my question...

Quote:
Originally posted by KoneKiller
Does increasing pressure in the hose leading to the actuator/wastegate controller (for lack of a better term... dashpot), cause the wastegate to open (reducing boost) or close (increasing boost)?
Vert... I have that question and also, why did you quit running that mod?

Thanks!!!
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Old 07-11-2003, 11:51 AM   #24
VetteVert
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Default Re: Re: Let me see if I can clarify my question...

Any restriction in the system before (before meaning closer to the compressor output) the factory Tee will decrease pressure to the actuator, increasing boost. Any restriction after the Tee will increase pressure on the actuator, generating less boost.

I quit running that mod because I now either run MBC (track) or leave the boost system stock (warranty...I'm a chicken). It creates an initial spike by way of removing restriction to the FBC. The FBC starts off operating at a set duty cycle. With the factory restrictor in place, this results in the 12-14psi normally seen on stock cars. With less restriction given by the larger connector, more boost escapes at the same duty cycle. HOWEVER, the ECU motors the MAP signal, and WILL adjust FBC duty cycle accordingly. This is the reason for the fluctuation after the initial spike. It did make a slight improvement, but after the ECU "learned" boost behavior, it was all but compensated for. If I was going to leave the boost system mostly stock, I would go the ABC aproach (or another Tee inline, with one outlet going to atmosphere or an adjustable mechanism) to keep the factory boost curve, just nudge it up a little.

VV

Quote:
Originally posted by KoneKiller


Vert... I have that question and also, why did you quit running that mod?

Thanks!!!
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Old 07-11-2003, 12:10 PM   #25
supermarkus
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I agree with VetteVert's assessment of this mod. On my stock WRX, it produced nothing but strange boost wavering at WOT due to the ECU trying to meet it's target boost profile. My boost would spike up quickly, settle down to around 12psi the creep back up to ~15psi then immediately drop to 12psi over and over again under WOT in 3-5 gears. I couldn't maintain WOT for long enough in 1-2 gears to see if boost wavered there since the car spooled up so quickly. But on my car and in my experience, this mod was garbage, I didn't like the feeling that my throttle was surging. Your ECU is given an authority range over your boost profile and it will do what it takes within that range to meet those targets. I'm sure people with more experience with these cars can outline exactly what it does. I'm guessing pulling timing to reduce load/exhaust velocity and changing boost control solenoid duty cycle are among the changes the ECU can make.
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