Embarrasing Question

[Damo_c]

I have a a stupid question, ive just installed a fmic. It didnt cum with a pin/connection for my boost cont welded in i found out after i started putting on the piping. Ive bought a little valve that i just screw into the piping from autobarn, the problem is cos ive never taken notive really of which pipe it went into on the stock one, i dont know which pipe i need to drill and tap it into. Can someone please tell me or show me a pic. Is it the one that goes from the turbo?

Please be gentle to me

[streetslider]

yes girls have boobs.

[Damo_c]

Since when????? So i assume that means yes it does!!

  streetslider said:

yes girls have boobs.

[Samon]

Technically it doesn't matter which pipe you tap into (i.e. hot (turbo-FMIC) or cold (FMIC-throttle)... but personally I tapped into the cold pipe... whichever is easier!

[Guilt-Toy]

tap it into the hot pipe closer to the turbo

[Basti]

but wouldnt the cold pipe see actual pressure after any drop through the cooler?

[RBwhatever]

I T'd mine out of the vacuum hose that goes from the bov to the plenum.

It works for me. But yeah hot pipe is probably better.

[Munkyb0y]

hot pipe is better. you'll get less variation in boost between hot and cold weather

[Damo_c]

Hot pipe itl be, thank you all for the sensible answers

[QWK32]

  Basti said:

but wouldnt the cold pipe see actual pressure after any drop through the cooler?

no. lets say you do put it on the cold pipe, eg: say you loose 1psi through your cooler, and you boost controller is set to 12psi, your turbo will actually be making 13psi, because of the pressure drop. you want your boost controller seeing the pressure that the turbo is making, thats why you put it on the hot side fairly close to the turbo.

[Basti]

  QWK32 said:

no. lets say you do put it on the cold pipe, eg: say you loose 1psi through your cooler, and you boost controller is set to 12psi, your turbo will actually be making 13psi, because of the pressure drop. you want your boost controller seeing the pressure that the turbo is making, thats why you put it on the hot side fairly close to the turbo.

cheers for that

[Samon]

  QWK32 said:

no. lets say you do put it on the cold pipe, eg: say you loose 1psi through your cooler, and you boost controller is set to 12psi, your turbo will actually be making 13psi, because of the pressure drop. you want your boost controller seeing the pressure that the turbo is making, thats why you put it on the hot side fairly close to the turbo.

But wouldn't it be better to have the boost controller seeing exactly what pressure is reaching the manifold... I mean I don't particularly care if my turbo is making 13PSI if the engine only sees 12... the 12 is what I want to limit yeah?

[QWK32]

  Samon said:

But wouldn't it be better to have the boost controller seeing exactly what pressure is reaching the manifold... I mean I don't particularly care if my turbo is making 13PSI if the engine only sees 12... the 12 is what I want to limit yeah?

you will care if your pushing the limit of the standard turbo, or any turbo for that matter. in then end you want your turbo producing the desired level of boost, and all the pipes and intercooler to have little effect on the overall pressure, you want the system to be the least restricting it can be, ie: using quality coolers with low pressure drop ratings.

[Sydneykid]

The problem with controlling boost via the pre intercooler pressure is that boost will slowly drop off at high rpm. Why? Because no matter how good it is, the intercooler and pipework will suffer some pressure drop. Plumbed into the pre-intercooler pipework, the wastegate actuator will not be receiving the actually boost pressure, hence the drop off at high rpm (actually airflow).

Cheers

Gary

[GeeTR]

QWK32 - Hrrm, I think I disagree. The turbos a means to an end, it just moves air up against the intake valves, a location I care more about regulated pressure then out the comp outlet of the turbo. Assuming your not constrained by turbo outlet pressure (stock ceramic) I think maybe the pressure there is borderline insignificant.

OP - For a manual BC, I'd take it from close to the TB. For a EBC, I would take the closed loop boost sender feed from same location, though take the wastegate feed from close the compressor outlet.

Its kinda moot in most setups Id say, and depends on the specifics. If you are boost limited by a stock turbo (and going along with boost/heat kills em) then the feed taken from the comp outlet would be the way to go, to insure you don't go over 13psi (or woteva it is)

If your motors tuned close to the limit with a aftermarket turbo and built motor and you know you start to det on a hot day at 24psi... well then the a TB/plenum source is the go.

Hope that made sense... 2 of them even:)

[Damo_c]

Ok, so im getting my bro in law to weld it to the piping, i have a turbosmart t-boost which i will be getting rid off soon for a ebc. I have a power fc - untuned atm, stock turbo, exhaust and now the fmic. I was guna get it welded off the turbo but as i am getting the ebc soon and the tune, what you are saying is that im better of getting it on the outlet piping so i think ill go that way. I didnt think it would cause this much of stir seeing as this is a turbo forum and i assumed people on here would have them in pretty much the same location as being the best position for them all.

Thank you