need expertise help on such a small puny discussion.

i know a lot of its stating the obvious while also not making sense. please give some feedback.. these are only bits and pieces cut out from the convo that was copy and pasted. im pretty confident in what i state (which a lot of isnt in this convo i pasted) but "a" seems so extremely confident in what he is trying to state that Im just gona have to post this here and confirm what I'm missing out on here cause a lot of stuff doesnt really make sense to me..basically a "whos right whos wrong" type deal. please discuss. tia

me: yea you loose boost up top
a: boost doest stop LOL
a: when you loose boost at the top mean you picked the wrong turbo for the car
a: because you dont pick an engine for a turbo
a: you pick a turbo according to your mods and engine
me:if this was true i think everyone that is power performance minded with a 2.0 wrx would buy the same turbo (i do realize some people want different things too)
me: of course u loose boost at some point
a: a right turbo wont loose boost on the top end

me: other factors would matter such as tuning, wg, exhaust, e/m, i/m, no?
a: you pick a turbo according to your mods and engine
a: what about those?
me: boosting at what rpm
me: where in the powerband boost comes and goes
a: that depends on the turbo
a: what turbo you get
me: hah k
me: so nothing else matters..

me: so theres a turbo out there that will keep me at 18 psi from idle to 7k?
me: or say from 2k
a: answer own stupid question justin
a: yes

a: if you get the right turbo you can keep boost without a problem
a: now you are picking a stock turbo for a car (vf series)
me: hm id like to find this turbo..
a: now the reason why boost dies
a: because it gives you power so fast it looses at the top
a: its called getting away from vf turbos
a: you have to get a manifold

a: well if you pick the right amount of boost you keep the turbo from dropping power on the top end
a: because if you boost the turbo to much it will "spike" and drop
a: but reason WHY YOU BOOST MORE IS BECAUSE YOU WANT MORE POWER
a: if you want more power then you need a diffferent turbo
a: because the turbo cant handle the boost you are pushing reason why it drops
a: understood?

me: then how come on my stock turbo
me: it can handle up to ~16psi
me: but at a point up top it drops?
a: ok how come your car comes stock with 13somthing psi?
a: tell me what it comes stock with
me: because thats what subaru wanted? maybe reliability/safety?
me: wrx stock is about 13
a: thank you
me: but can handle up to like ~16+
a: now does boost drop at 13 psi
me: your welcome lol
me: of course because thats a stock wrx max
a: at 13psi boost drops? after 6k
me: yea
me: right now im running 16 psi, cause its set it that way
me: and it drops after 6k as well
a: your engine doesnt hold a 13psi all the way thru the power band?

not making sense....

tia

 

my head hurts from reading this.

what exactly is your question?

 

sorry shouldve just asked specific questions but i was just copying and pasting in a rush last night. i bascially wanted to see if he was making any sense at all in what hes talking about~ basically a question i would have is:


-are there turbos out there that hold full boost from bottom, all the way to redline? (

-wouldnt other other factors come into play when talking about boosting at what rpm and where in the powerband boost comes and goes? such as tuning, piping, etc?

-
ill coninue later dam have to be at work..

 

you are suppose to bleed off the bost up top in the tuning.
a weak wastegate can also be teh problem not just teh wrong turbo

me: yea you loose boost up top
a: boost doest stop LOL
a: when you loose boost at the top mean you picked the wrong turbo for the car
a: because you dont pick an engine for a turbo
a: you pick a turbo according to your mods and engine
me:if this was true i think everyone that is power performance minded with a 2.0 wrx would buy the same turbo (i do realize some people want different things too)
me: of course u loose boost at some point
a: a right turbo wont loose boost on the top end

 

i dont understand teh second -

but every turbo has lag

look into a twin scroll

 

that depends on what you consider "bottom."

basically if you get a pretty decent/reasonable turbo you'll get ~3k rpms worth of very efficient, high pressure ratio, high air flow operation. 4k if you're lucky.

where you locate that sweet spot determines how streetable or how powerful the car is. low rpm sweetspot = easy to drive around town. high rpm sweetspot = highway/dragstrip monster.

 

me: so theres a turbo out there that will keep me at 18 psi from idle to 7k?
me: or say from 2k
a: answer own stupid question justin
a: yes

haha which one is that because ill go buy it
how much CFM is it flowing 1/2?



me: then how come on my stock turbo
me: it can handle up to ~16psi
me: but at a point up top it drops?
a: ok how come your car comes stock with 13somthing psi?
a: tell me what it comes stock with
me: because thats what subaru wanted? maybe reliability/safety?
me: wrx stock is about 13
a: thank you
me: but can handle up to like ~16+
a: now does boost drop at 13 psi
me: your welcome lol
me: of course because thats a stock wrx max
a: at 13psi boost drops? after 6k
me: yea
me: right now im running 16 psi, cause its set it that way
me: and it drops after 6k as well
a: your engine doesnt hold a 13psi all the way thru the power band?


meh i had my stock turbo pulling 1.5 bar all the way to redline

 

That convo hurt. lol slap your friend for me he didnt make any sense :/

 

Let him have fun keeping full boost at redline in his car then. Your "freind" was trying to get accross (very poorly), that there is boost taper due to the turbo's flow capacity. However, I'd like him to show me a turbo that can run at 18psi from 2K - 7K RPMs. Ha!

When running at 7K RPMs with a TD04 at 17psi, you are out of the turbos effiency range. It can't handle the amount of flow it would take at that engine speed. So, with a larger flowing turbo and proper tuning, you can run 17psi at 7K RPMs. Don't confuse that with a turbo at it's maximum boost at redline because most conventional turbos aren't designed to flow at their maximum at such a high engine RPM.

Did this help at all?

 

ummm... yeah.

got a log of that?

 

yes most of this is what i thought, makes sense thanks for the response and feedback guys.

in the convo it seemed like he was trying to get this across to me: in whatever setup/car you run along with the "perfect" turbo (because apprently the turbo itself is all that matters) you should **always** run strong w/ full boost till redline.
i believed there were other factors involved, of course along with the correct tuning for the way youd want to run your car) such as wastegate, different piping throughout the engine, etc. maybe my engrish isnt making sense either due to my speech skills haha.