DIY Turbo Discussion greddy on a 1.8? homebrew kit?

A question about my odd BOV

Thread Tools
 
Search this Thread
 
Old 11-02-2007, 10:59 AM
  #21  
Junior Member
iTrader: (1)
 
PAT!'s Avatar
 
Join Date: Sep 2006
Posts: 464
Total Cats: 0
Default

Crap. I missed that too. Now your valve will probably leak boost on tip-in or maybe even longer what with the spring being cut.
PAT! is offline  
Old 11-02-2007, 11:00 AM
  #22  
Junior Member
iTrader: (1)
 
PAT!'s Avatar
 
Join Date: Sep 2006
Posts: 464
Total Cats: 0
Default

...but then again thats like someone wondering why their car isn't starting after its run out of gas.
PAT! is offline  
Old 11-02-2007, 11:24 AM
  #23  
Ben
Supporting Vendor
iTrader: (33)
 
Ben's Avatar
 
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,659
Total Cats: 134
Default

Yeah hopefully your BOV won't leak boost. Leave the boost gauge hooked up where it is so you can watch for any pressure loss compared to what you're used to seeing. You should be able to hear it leak if it does, too.
__________________
Chief of Floor Sweeping, DIYAutoTune.com & AMP EFI
Crew Chief, Car Owner & Least Valuable Driver, HongNorrthRacing

91 Turbo | 10AE Turbo | 01 Track Rat | #323 Mazda Champcar

Originally Posted by concealer404
Buy an MSPNP Pro, you'll feel better.
Ben is offline  
Old 11-02-2007, 12:09 PM
  #24  
Junior Member
iTrader: (1)
 
PAT!'s Avatar
 
Join Date: Sep 2006
Posts: 464
Total Cats: 0
Default

Well its not the peak boost that is a concern, it takes a pretty crap valve to leak once peak boost is reached. Its boost onset that is the problem.

Look at the dyno below. Independent 3rd party dyno test on a stock 06 STi and with our recirc valve installed. Valve install done on the dyno in between runs and the car was brought to the same temp for both runs.

The weak spring in the factory valve is being blown open due to latency and pressure drop. Once this happens there is a far greater surface area available to the charge air to act upon than normal, keeping the valve open even if the intake manifold side of the valve and the charge pipe side reach equilibrium. When this happens the only thing that will close it is the difference between the two coming from the spring.

Being that your valve is compressor mounted it will be seeing the highest possible pressure on the bottom of its diaphragm, so the problem will likely be magnified.


Last edited by PAT!; 11-13-2007 at 10:54 AM.
PAT! is offline  
Old 11-02-2007, 09:39 PM
  #25  
Elite Member
Thread Starter
iTrader: (12)
 
cardriverx's Avatar
 
Join Date: Jan 2007
Location: Hermosa Beach, CA
Posts: 2,573
Total Cats: 12
Default

Ok guys, I put a spacer behind the spring (to lengthen it alittle), changed the line to over at the TB, and it works perfect! It has a cool whistle to it, ill take a vid sometime (its acually pretty darn loud!). Nor does it leak.

Also, I relocated the boost gauge to the TB, and found out im acually boosting only 3 to 4 psi with the intercooler drop factored in! so..

thanks to my school's auto lab having an account with grainger, I made a "grainger MBC" for $10 =). Turned the boost up so it just kisses 5 psi, and it runs beautiful!

QUESTION - I hooked the boost gauge where the charchol chanister was, and took off the line to the charchol canister. I ran it for a lil like that.. is that ok? Do I need to hook it up ASAP?
cardriverx is offline  
Old 11-02-2007, 10:11 PM
  #26  
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,091
Total Cats: 7
Default

You don't really need the charcoal cannister. Pretty sure it just catches gasoline vapors so they don't get into the atmosphere.
cjernigan is offline  
Old 11-02-2007, 10:56 PM
  #27  
Elite Member
Thread Starter
iTrader: (12)
 
cardriverx's Avatar
 
Join Date: Jan 2007
Location: Hermosa Beach, CA
Posts: 2,573
Total Cats: 12
Default

Originally Posted by cjernigan
You don't really need the charcoal cannister. Pretty sure it just catches gasoline vapors so they don't get into the atmosphere.
I know it does that, im just wondering if haveing it unhooked will mess with fuel vapor in the tank or anything.
cardriverx is offline  
Old 11-02-2007, 11:50 PM
  #28  
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,091
Total Cats: 7
Default

You should be fine. I would get my signal from somewhere else though. You have the fitting on the back of the mani and the ones at the TB. Or you could put a T into your brake booster line and get it from there, that would work well. Either way I don't see you having your CC unhooked being a problem. rmmcelwe and mxv don't run one.
cjernigan is offline  
Old 11-02-2007, 11:52 PM
  #29  
Elite Member
Thread Starter
iTrader: (12)
 
cardriverx's Avatar
 
Join Date: Jan 2007
Location: Hermosa Beach, CA
Posts: 2,573
Total Cats: 12
Default

Where exactly is the one on the back of the mani? I cannot seem to find it.
cardriverx is offline  
Old 11-02-2007, 11:54 PM
  #30  
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,091
Total Cats: 7
Default

What year is your car. You might not have one. Most cars have a fitting between on the backside near the firewall. I have a '99, hard to relate to NAs.
cjernigan is offline  
Old 11-03-2007, 12:06 AM
  #31  
Elite Member
Thread Starter
iTrader: (12)
 
cardriverx's Avatar
 
Join Date: Jan 2007
Location: Hermosa Beach, CA
Posts: 2,573
Total Cats: 12
Default

93
cardriverx is offline  
Old 11-03-2007, 01:07 AM
  #32  
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,091
Total Cats: 7
Default

Do you have this?
cjernigan is offline  
Old 11-03-2007, 12:06 PM
  #33  
Elite Member
Thread Starter
iTrader: (12)
 
cardriverx's Avatar
 
Join Date: Jan 2007
Location: Hermosa Beach, CA
Posts: 2,573
Total Cats: 12
Default

yes I do. I was wondering if it was ok to tee into the FPR, thanks =)
cardriverx is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
bigmackloud
Miata parts for sale/trade
19
01-08-2021 11:24 AM
StratoBlue1109
Miata parts for sale/trade
21
09-30-2018 01:09 PM
JesseTheNoob
DIY Turbo Discussion
15
09-30-2015 02:44 PM
itsMikey
MSPNP
3
09-28-2015 06:40 AM



Quick Reply: A question about my odd BOV



All times are GMT -4. The time now is 09:33 PM.