Volume vs pressure

[Guest keltik]

....no

[Koom]

 pl0x']

[quote name='boostin said:

How easy is it to pull the externals spring out? You won't be boosting it after that!

/quote]

easy as, would just sound like a mass exhaust leak tho?

Not if its set up properly and plumbed back into the exhaust.

[pl0x]

this is true.

would everything still work fine with the waste gate spring out? just no boost?

[Koom]

It would be better for him to drive it like that as at zero boost the tune will be much safer. Still not ideal. And you're much better off if you can check a few things yourself (i.e. Det, A/F ratio) to make sure its ok.

[dubbedup]

I popped an intercooler join at a casual grass autocross earlier this year and drove it round like and N/a for 2 laps....slow as!

this situation just keeps getting worse...rather knowaobut it now...any other issues people have had in the past?

[Guest]

Might be a weekend mish with a trailer bro!! or i could tow ya with the missus wee crolla hahha its got a tow bar lol

[dubbedup]

hahahaha, na mrs got a tow ball and i think the people mover does too...lmfao!

[Guest]

who's got a car trailer in dunners?? =D

[dubbedup]

how goods your towing skills? wont be the 1st time i've done a big tow.

Apparantly the prez got one and my mates got a massive one we can possibly use....

[Guest]

iv done a few long haul tows, one with an old 76mitsubishi lancer with no windscreen haha wasn't very nice catching bugs with your face

[dubbedup]

yeah i think trailer be the best option.....

[Guest boostin]

Chicken. Where's your commitment?

[Guest]

 dubbedup said:

This is going to sound dumb as but I have been discussing with a few mates about big turbos... one thing that comes up is volume vs pressure....btw none of us are turbo experts.

For arguements sake I have a vf22 set to 10psi with a ex.wastegate controlling boost, then i upgrade to a t70 with the same setup, still running 10 psi but is the volume larger??

Afterthoughts:

It is my thinking that 10psi is 10psi but if thats the case is there anypoint on putting a bigger turbo unless you need more than 18psi (maxing out the vf22??)

Its all about flow. A bigger turbo will flow more air and make more power at the same boost.

10psi is 10psi on the cold side but a bigger turbo has a bigger turbine/hot side. So the exhaust flows much better.

With turbo cars egbp kills power - bigger turbos have lower egbp thus make more power

[Guest]

 Qwerty']

[quote name='dubbedup said:

This is going to sound dumb as but I have been discussing with a few mates about big turbos... one thing that comes up is volume vs pressure....btw none of us are turbo experts.

For arguements sake I have a vf22 set to 10psi with a ex.wastegate controlling boost, then i upgrade to a t70 with the same setup, still running 10 psi but b]is the volume larger??[/b]

Afterthoughts:

It is my thinking that 10psi is 10psi but if thats the case is there anypoint on putting a bigger turbo unless you need more than 18psi (maxing out the vf22??)

Its all about flow. A bigger turbo will flow more air and make more power at the same boost.

10psi is 10psi on the cold side but a bigger turbo has a bigger turbine/hot side. So the exhaust flows much better.

With turbo cars egbp kills power - bigger turbos have lower egbp thus make more power

I only want to say one thing really, IMO you can't run more boost if you can't flow that extra volume of air through the head regardless of what size you have?

[dubbedup]

thats cool, i dont intend to work on the heads just yet to get them to flow more, i merely started this thread to find out if i put a bigger turbo on with an external wastegate, will i be able to drive it....without blowing up my motor

[Guest]

Yes I know, my point was, drive it with the lowest amount of boost you can, as you would know already , volume & pressure are related by Area , air travels from your intake into your cylinder purely by the difference in pressure between the two. You would be running low pressure high flow but it’s only going to take in what it can take in. I think I might need to go more in-depth but will see.

[dubbedup]

I have learnt way more from this thread than i thought i ever would have, but if you feel like going into depth, im more than happy to listen....still have to read keltiks turbo link, the more info i get the better choices i can make.

[Guest]

 WiLd02StI']

[quote name='dubbedup said:

This is going to sound dumb as but I have been discussing with a few mates about big turbos... one thing that comes up is volume vs pressure....btw none of us are turbo experts.

For arguements sake I have a vf22 set to 10psi with a ex.wastegate controlling boost, then i upgrade to a t70 with the same setup, still running 10 psi but b]is the volume larger??[/b]

Afterthoughts:

It is my thinking that 10psi is 10psi but if thats the case is there anypoint on putting a bigger turbo unless you need more than 18psi (maxing out the vf22??)

Its all about flow. A bigger turbo will flow more air and make more power at the same boost.

10psi is 10psi on the cold side but a bigger turbo has a bigger turbine/hot side. So the exhaust flows much better.

With turbo cars egbp kills power - bigger turbos have lower egbp thus make more power

I only want to say one thing really, IMO you can't run more boost if you can't flow that extra volume of air through the head regardless of what size you have?

at some point yes but

if the heads are the restriction more boost does work

[Guest]

Yes/No because that restriction is its max volume of air it can take regardless of pressure, more pressure = less volume

[Koom]

 WiLd02StI said:

Yes/No because that restriction is its max volume of air it can take regardless of pressure, more pressure = less volume

Not really. Its a mass flow equation and not a volume flow one and the restriction is the port area (there's also alot of dynamic stuff going on which the VE accounts for).

But simplified, more pressure = greater mass of air entering the cylinder volume. Which if that's matched with more fuel and timing in the right spot = more power.

[Pappu1]

 Qwerty']

[quote name='dubbedup said:

This is going to sound dumb as but I have been discussing with a few mates about big turbos... one thing that comes up is volume vs pressure....btw none of us are turbo experts.

For arguements sake I have a vf22 set to 10psi with a ex.wastegate controlling boost, then i upgrade to a t70 with the same setup, still running 10 psi but b]is the volume larger??[/b]

Afterthoughts:

It is my thinking that 10psi is 10psi but if thats the case is there anypoint on putting a bigger turbo unless you need more than 18psi (maxing out the vf22??)

Its all about flow. A bigger turbo will flow more air and make more power at the same boost.

10psi is 10psi on the cold side but a bigger turbo has a bigger turbine/hot side. So the exhaust flows much better.

With turbo cars egbp kills power - bigger turbos have lower egbp thus make more power

I only want to say one thing really, IMO you can't run more boost if you can't flow that extra volume of air through the head regardless of what size you have?

at some point yes but

if the heads are the restriction more boost does work

you could increase the pressure wwithout increasing the airflow - increase the heat or temp of the gas and for the same flow u have more pressure

basically, a larger turbo flows cooler air once u reach higher pressures as compared to a smaller turbo running at max..

e.g. u can flow x amount of air on a small turbo for say 18psi and that will be at a certain temp - near max of the the turbo ability

if there is a larger turbo flowing the same pressure it will have lower temp and even if the air flow is the same..

colder temp will make more power for the same PSI

[Swindog]

Or just do it safe with a trailer and then theres no probs. Hiring a car trailer will only cost $50 buck for the weekend surely. If you can borrow one sweet as if not take the hit and do it right.

[dubbedup]

nah its 90$ a day for trailer hire in DUnedin, Cheapest i could find too. but i know some boys who will loan the trailer for a 24 box or something.

[Swindog]

Still cheaper than driving it up and effing something on the way, cos youll get stuck behind a truck and wanna boost it to pass etc or the kilmog. Safe = right. Sometimes.

[dubbedup]

Yeah, i will do all the setup and test it but not drive it, and trailer it up. I agree, play it safe rather than be sorry