TMIC BOV questions.

courtjesterclown · Post by **courtjesterclown** » Mon Apr 14, 2008 10:27 pm

SO from what i've seen most ppl. on here try and retain their stock BPV when upgragiding to a top mount intercooler. OTher than the extra cost issue, if you have an aftermarket BOV that is properly recirculated are there any more problems associated with using an aftermarket BOV dump. Also, for those who are running aftermarket BOV's, any certain brand? and where did you recirc it back into?

SubaruNation · Post by **SubaruNation** » Tue Apr 15, 2008 1:36 am

it's because our cars have the MAF sensor (right away), so BOV's without recirculation are pointless pretty much.

the air is basically wasted i believe w/out the recirc

Post by **Legacy777** » Tue Apr 15, 2008 2:38 am

SubaruNation wrote:the air is basically wasted i believe w/out the recirc

To add on this. Without the air being recirculated, at that moment when you're dumping the excess air to atmosphere, the engine will run rich because the MAF sensor measured the amount of air coming into the engine & the ECU delivered the cooresponding amount of fuel. But when you dump the air to atmosphere, the fuel calc is not correct any more....and you run rich.

SubaruNation · Post by **SubaruNation** » Tue Apr 15, 2008 3:09 am

Legacy777 wrote:
SubaruNation wrote:the air is basically wasted i believe w/out the recirc
To add on this. Without the air being recirculated, at that moment when you're dumping the excess air to atmosphere, the engine will run rich because the MAF sensor measured the amount of air coming into the engine & the ECU delivered the cooresponding amount of fuel. But when you dump the air to atmosphere, the fuel calc is not correct any more....and you run rich.

thanks josh,

yeah that's what i was trying to say...sort of lol

keirnna · Post by **keirnna** » Tue Apr 15, 2008 5:30 am

There are after market 100% recirculating valves that hold more boost and are stronger than the OEM ones. Forge makes a lot of them.

courtjesterclown · Post by **courtjesterclown** » Tue Apr 15, 2008 5:34 am

Exactly, but if the air is recirced back into the intake then the ECU actually doesnt even know it went a different path and should give a steady air/fuel mixture. So, anybody know for sure what style of BOV to use, so that it doesnt hit the cruise and throttle cables? Also, for the stock vf-11 turbo outlet which i believe has a 45 deg. angle, would a silicone 90 be correct for the angle for the pipe to the intercooler? anybody know the diameter of the turbo outlet off hand? I dont have the car up here, so i cant measure.

keirnna · Post by **keirnna** » Tue Apr 15, 2008 5:47 am

The turbo outlet is 2". I haven't seen the turbo legacy so I am not sure, but I know how the TMIC is on the EJ20G. You can re-route the BOV if you need to. Forge make an exact replacement for the EJ20G OEM BOV that is metal. Here it is: http://www.forgemotorsport.com/content. ... =FMDVMSP02

BXSS · Post by **BXSS** » Tue Apr 15, 2008 1:20 pm

If the turbo that was on the TMIC car had a 90* turbo outlet a 45* silicone connector may work (I've seen 45*, 60*, & 90* silicone connectors available).

I can't say for sure as I never did a TMIC install when my car was VF11.

SubaruNation · Post by **SubaruNation** » Wed Apr 16, 2008 12:39 am

courtjesterclown wrote:Exactly, but if the air is recirced back into the intake then the ECU actually doesnt even know it went a different path and should give a steady air/fuel mixture. So, anybody know for sure what style of BOV to use, so that it doesnt hit the cruise and throttle cables? Also, for the stock vf-11 turbo outlet which i believe has a 45 deg. angle, would a silicone 90 be correct for the angle for the pipe to the intercooler? anybody know the diameter of the turbo outlet off hand? I dont have the car up here, so i cant measure.

i did a whole thread on this

ha ha

here...

http://bbs.legacycentral.org/viewtopic.php?p=245673

on the last page i believe.

there's a link there too so you can get the right one

courtjesterclown · Post by **courtjesterclown** » Mon May 05, 2008 7:02 pm

SO the elbow i need to get is for sure 1.5 inside diameter? i hate buying something then having to return it. and am i correct in thinking the throttle body to TMIC coupler is 3 inch id?

SubaruNation · Post by **SubaruNation** » Mon May 05, 2008 9:00 pm

dam, i want your car.

uh, i still can't measure.
that does sound correct though.

Edit: whatever the OD of your throttle body is... what you need for ID of the coupler.

see below

SubaruNation · Post by **SubaruNation** » Mon May 05, 2008 9:15 pm

from here http://bbs.legacycentral.org/viewtopic. ... 16&start=0

i found this:

8 - Collar between IC and Throttle body - we sawed off as much of the throttle body metal inlet as we could to fit the IC in without hitting the firewall. [b]We used the stock WRX rubber hose to connect the throttle body to the IC outlet[/b]. It had to be cut down, and in particular it had to be cut at an angle since the IC was mounted at an angle relative to the throttle body. [EDIT - this damn collar blew off the throttle body at several rallycrosses in a row. Make sure it's as long as possible so it can reach even when the engine and intercooler move around. Also make sure it's clamped as well as possible.]

DONT CUT YOUR THROTTLE BODY AT ALL. just to make sure.
the thread i posted is for a different IC than you are installing.

look through my install journal, and other people's for more info and use the search section. it kicks ass

courtjesterclown · Post by **courtjesterclown** » Mon May 05, 2008 11:44 pm

Thanks bro. car isnt with me right now as im at school so i cant measure. but i'll get on that as soon as i get back to it. WHat, you want this ol ABM? haha she let me down a few nights ago, got stuck in park while i was out on a date. an hour and a half later me and the chick got the override down and we hauled ass out of the parkin lot. yeeeehaw.

the_watts10 · Post by **the_watts10** » Tue May 06, 2008 4:23 am

so what im getting from this is that a bov wont work on stock ecu but some guys have said that the BOVs work fine on there cars?
if not what up grades are necessary?

courtjesterclown · Post by **courtjesterclown** » Tue May 06, 2008 6:51 am

a BOV will work, but your car wil most likelyl run rich everytime the bov dumps atmospherically.

SubaruNation · Post by **SubaruNation** » Wed May 07, 2008 3:52 am

well it's also (can be i guess) recirculated.

kinda a waste b/c the MAF is b4 the dump

and CjC: i wanted to have 2 abm cars for awhile, thats Y

asc_up · Post by **asc_up** » Wed May 07, 2008 5:31 am

the_watts10 wrote:so what im getting from this is that a bov wont work on stock ecu but some guys have said that the BOVs work fine on there cars?
if not what up grades are necessary?

Basically, your car will work with a BOV instead of a BPV, but it just won't be running as well as it could. With the BOV all of the air metered by the MAF gets blown off into the atmosphere instead of back into the system. This causes there to be less air in the system than the ECU thinks. So because the ECU thinks there is more air in the system, it dumps more fuel. But in reality there's actually less air and then an assload of fuel.

The car will run, BUT you'll run extremely rich between shifts which will cause a bit of 'lag' when you hit your next gear but it'll still run fine.

Expect backfires if you do this...

the_watts10 · Post by **the_watts10** » Thu May 08, 2008 5:45 am

thats all good my friend i love to hear backfiring as long as it doesnt run to much crappier?

asc_up · Post by **asc_up** » Thu May 08, 2008 5:50 am

I know a few people running atmospheric BOVs and it really doesn't seem to run that bad.

IronMonkeyL255 · Post by **IronMonkeyL255** » Thu May 08, 2008 6:44 am

BTW, the turbo outlet is ~1.75" OD.

I got a 1.75"ID elbow, and it fit the outlet well.

IronMonkeyL255 · Post by **IronMonkeyL255** » Thu May 08, 2008 7:02 am

I just ordered the Forge unit for my SS (anodized black, of course).

asc_up · Post by **asc_up** » Thu May 08, 2008 8:32 am

Cool. Let us know how it works.

IronMonkeyL255 · Post by **IronMonkeyL255** » Sun May 11, 2008 7:52 pm

Well, I'm gonna have to wait.

There aren't any in the country. The soonest I will see it is next friday, and that is assuming it is in stock in the UK.

Oh, well. I am in no huge hurry. I also ordered a silicon coupler for the i/c to t/b connection, a new 45 degree bend for the turbo to i/c connection, and I intend to epoxy together one of my BPV fitting parts I just had screwed together and teflon-taped. HOPEFULLY one of these is my culprit for my fluctuating boost signal. If not, then I have no freaking clue what it could be.

courtjesterclown · Post by **courtjesterclown** » Mon May 12, 2008 3:50 am

ironmonkey, what is the 45 bend for? i ordered a 90 silicone bend to fit off the turbo, then should i get the mandrel 45 to hook the 90 up to the y-pipe on the intercooler? any idea how long to make it. using a 06 WRX TMIC.

SubaruNation · Post by **SubaruNation** » Mon May 12, 2008 6:03 pm

he might be using a different turbo/tmic.

then should i get the mandrel 45 to hook the 90 up to the y-pipe on the intercooler?
ya

any idea how long to make it. using a 06 WRX TMIC.
you will know when you put it together, have some exhaust shop fab you up a pipe with that angle and you'r golden. you will end up cutting it down.
as long as it has the angle, and like 9 '' for safe measure you should be ok

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TMIC BOV questions.

TMIC BOV questions.