Boost Reading

[airbornesoldier]

Hi all,

Wheres the best place for boost line hook in for a boost guage?

[paulr33]

the best place is next to the compressor outlet

that way you take out any loss from the pipework, intercooler core and other junk along the way

if you look at pics of the HKS 2835 ProS youll see the actuator gets a signal from its own compressor cover, this is the ideal way

but most common places are intercooler pipe work before the intercooler is fine

[GeeTR]

^^ for boost feeds for actuators, but for your boost gauge, you'll want it post TB so it will read vacuum as well

[CEF11E]

the best place is next to the compressor outlet

that way you take out any loss from the pipework, intercooler core and other junk along the way

if you look at pics of the HKS 2835 ProS youll see the actuator gets a signal from its own compressor cover, this is the ideal way

but most common places are intercooler pipe work before the intercooler is fine

this is 100% right unless you have a turbo with a large compressor wheel and very small housing. an example would be a bax oversize rb20 turbo. there is to much turbulance and pulsing to get a steady pressure.

in this case you are best off getting your feed 10 to 20 cm away from the compressor housing. I have found the profcb and other solenoid ebc's do not cope well with turbulant boost scources. this is due to the sample rate they use and their limited processing ability.

cheers

[WAN73D]

CEF11E and Paulr33..... i don't mean to take nything away for you guys as ur right in your application

BUT i believe airbornesoldier is talking about a line for a BOOST GAUGE...the usual place for a mechanical gauge is to just tee into the stock like which comes out from the back of the plenum (my old r32 did anyway).

unless im missin something here i think u guys are talking about the boost line from turbo to actuator to control wastegate...this is entirely different to boost pressure reading line for gauge and i thought i've read here that that actuator line should never be used as a boost reading.

a) because it'll add a bit of overboost

b) if somethin goes wrong at gauge side of things you've very possibly got infinate boost!

[Housie]

CEF11E and Paulr33..... i don't mean to take nything away for you guys as ur right in your application

BUT i believe airbornesoldier is talking about a line for a BOOST GAUGE...the usual place for a mechanical gauge is to just tee into the stock like which comes out from the back of the plenum (my old r32 did anyway).

This is the way i plumbed it on my r33. Teed it off the vacum hose coming out of the plenum (where the stock boost guage gets its reading i believe). Stock Guage and Aftermarket digital guage both work nicely.

I think the main thing is to make sure its after the FMIC, otherwise your reading the boost the turbo is making rather than the boost at the engine.

[sonoramicommando]

i d go along with what WAN73D & Housie are saying. I also T'd off a nipple at the back half of the plenum (R32 RB25DE+t).

I think I'll put individual nipples for BOV, boost gauge, wastegate actuator feeds, now I have the plenum out for fwd facing plenum mod - it was getting too messy with T off another T etc.

At the same time I'm putting a spare boost gauge at the compressor housing, just to be sure of what boost the turbo is making before all the pipework - I hear 25DET turbo is good for 12 psi ish at turbo and wanna make sure it's below that at turbo.

[34skyline]

T-piece off the standard blow off (by pass) valve, That seems to be working fine for me.

[r33cruiser]

^^^^

Much of a muchness cant really fark it up.

Its when you want to get a source for a boost controller that u REALLY want something near the compressor cover.

[geraus]

I just got my boost signal right of the stock line, pulled that one out and put it straight to my boost gauge, its at the end of the plenum. And my boost controller signal is connected to my fuel regulator line.