No Boost...Help!!!

[kiri]

My t25 took a dump on me 2 days after buying a Talon so I wanted to do some upgrades. I did these upgrades all posted below and installed the new big 16g and started the car just to make so I wasnt having the same issue as I was before with a blown t25. The car idled after a little squeeking from the oily belts. But it idled. I gave a little throttle to check to see if it was making boost and it was NOT. :-/ I searched and searched, I checked and checked (vaccum lines, leaks, fluids, etc etc) and no luck. So here I am..

95 Talon Tsi Awd 7 Bolt with

Exhaust headers, Apex 3in downpipe, megan 3 inch exhaust, ported o2, aftermarket whatever uic pipping, SAFCII, stock injectors(evo560'a not installed yet), stock pump, (255 not installed yet), autometer boost, oil press gauges, Halman MBC(8-10 psi on my troubleshooting start up),Blitz turbo timer, dejon style Intake Pipe, KN filter, new upstream 02, Big 16G, 16G install kit, hacked oil return pipe, Free mods-honey combs out, screw backed flush, and can't think of anything else right now.

So the issue is What am I missing? Did I overlook something to check on why I am not producing boost?
Side Note I had a lil exhaust back fire..Not sure how in the world I would be running rich on 450's with a big16g. But anyways I believe that is all the info I can think of as of right now. If more info is needed I will be checking this every few hours of the day for the next few days. Thanks in Advance and I am sorry if I posted this in the wrong area.

 

[Captn]

You're not getting boost at a stand still or while driving?

 

[assassin3117]

Im confused here as well. Have you driven the car and verified your not getting boost while driving?

 

[kiri]

No, It was in N while reving I made no boost. I was to afraid to drive it. I brought the Rpms high as 4200

 

[Bling_23]

I would take it out for a drive and try to build boost under a load.

 

[kiri]

Ok, but why would it even make a difference?

 

[tay97gst]

You most likely wont make boost just in neutral reving. Ive read that they dont make boost at idle because it isnt enough load on the engine or something. I guess you wont know if youre voosting until the road test. I may be wrong but i know for sure my car doesnt boost in neutral.

 

[kiri]

Ok, I will double check and get back with results.

 

[zcoh2gdsm]

you really wont build boost in neutral without anti-lag, you need to have a load on car to build boost, take it out for a quick spin around the block and report back.

 

[kiri]

I am going to drop it off stands, double check fluid levels and take it for a quick spin tomorrow morning. I will report back but feel baffled that it wouldn't build boost revving in N. Is there a logical or mechanical explanation of exactly why it does not build boost in N? Thanks in advance for everyone's advice and comments.

 

[Kng Nothg]

it wont build boost since the motor isnt underload pushing out the pressure needed to build boost

 

[AllShallPerish]

I am going to drop it off stands, double check fluid levels and take it for a quick spin tomorrow morning. I will report back but feel baffled that it wouldn't build boost revving in N. Is there a logical or mechanical explanation of exactly why it does not build boost in N? Thanks in advance for everyone's advice and comments.

You sound extremely ignorant to the operation of a turbo.

No, you cannot build boost in neutral unless you have a 2 step. You may be able to build 1-5 psi momentarily but feathering the pedal at 5-7k in neutral, however that is not the best idea.



You should take some time to read and understand how a turbo system works. You dont want to be that guy who talks about his car and everyone around goes like this


It's the mass and velocity of the gasses flowing. thermal expansion due to the heat does help, but heat alone will only make things hot. at 5k rpm no load, the throttle is barley open and very little fuel is being burned. at 5k rpm full load you have max air and max fuel combusting. much higher cylinder pressures, much higher mass and velocity of gasses flowing through the turbo.
There is much more to it, but this is the basic answer.

 

[nfernotalon]

Car needs to be under load. Or launch control, 2 step or antilag.

You should take some time to read and understand how a turbo system works. You dont want to be that guy who talks about his car and everyone around goes like this


Too late . Everyone has to learn sometime.

 

[Roberti 2G]

Need load to build boost. That is your logical or mechanical explanation. So was that the only reason u thought the t25 was blown cause it didnt make boost in N?

 

[kiri]

no that's not the reason I thought the T-25 was blown and yes you were all right it was making boost under load.

 

[GST with PSI]

You sound extremely ignorant to the operation of a turbo.

No, you cannot build boost in neutral unless you have a 2 step. You may be able to build 1-5 psi momentarily but feathering the pedal at 5-7k in neutral, however that is not the best idea.



You should take some time to read and understand how a turbo system works. You dont want to be that guy who talks about his car and everyone around goes like this


It's the mass and velocity of the gasses flowing. thermal expansion due to the heat does help, but heat alone will only make things hot. at 5k rpm no load, the throttle is barley open and very little fuel is being burned. at 5k rpm full load you have max air and max fuel combusting. much higher cylinder pressures, much higher mass and velocity of gasses flowing through the turbo.
There is much more to it, but this is the basic answer.

Look man, the OP doesn't seem to know a lot about turbos. Cool, he will get it with time. Before you call someone ignorant you should be more familiar with turbo operation yourself...

Exhaust energy is determined by its temperature, not its pressure, mass or anything else. In order to extract energy from the hot gas, you must drop the pressure across the turbine. Differential pressure is what drives the turbine, it's what drives any turbine, whether it's steam turbine, jet turbine..whatever. Without differential pressure there would be no flow (or velocity). The pressure and temperature drop (gas expanding) that occurs across the turbine provides the power necessary to drive the compressor. You can't build boost revving in neutral because normally, it's not possible to produce the required heat energy to make boost.

For example: Operating your engine under a load produces higher cylinder pressures, and a more dense air/fuel charge can be burned (much in part due to the turbocharger being put to work at this point), producing even more heat. This allows the turbine to create more exhaust back pressure on the engine. The higher engine exhaust back pressure is, the higher the pressure differential across the turbine is.

(Exhaust back pressure in this case meaning pressure between engine and the turbocharger's turbine.)

You need to increase the heat energy being exhausted by each cylinder against the turbine. Weather by increasing engine load, using an anti-lag, 2 step etc doesn't matter. Bottom line, it's virtually impossible to do this at any length simply revving in neutral.

 

[GST with PSI]

seriously?

I just read your post, you seem to be misinformed as well. So before you go trying to start arguments on this topic, you might want to do some studying.

Being ignorant on a subject is not in anyway a bad thing if you are willing to learn.

Either way, It really does not matter. It does not relate to this thread anymore. The problem the OP had is resolved.

This is not the time or place for an argument. If you want to debate fundamental turbocharger operating principals, open a thread.

Are you serious? I'm not starting an argument, simply pointing out you are completely wrong, and calling others ignorant when in fact you are ignorant yourself. If something I said isn't true, feel free to point it out. I don't need to start a new thread to debate anything with you, because anyone who reads this one will know you incorrect, and that you should "study" as you put it. Why don't you start by "studying" the first law of thermodynamics. Better yet, skip all that, and just Google "Internal Energy of an Ideal Gas". It will get straight to the point...

 

[avefenix]

to be honest i learned something new on this today...i never really paid attention to the neutral gear and revving the engine to know it didnt create boost, im new to the tuners but if theres one thing i know it is alcohol running engines, thanx for the newly learned lesson today gentleman....ill go try this out and watch for myself

 

[ShadyGST]

Are you serious? I'm not starting an argument, simply pointing out you are completely wrong, and calling others ignorant when in fact you are ignorant yourself. If something I said isn't true, feel free to point it out. I don't need to start a new thread to debate anything with you, because anyone who reads this one will know you incorrect, and that you should "study" as you put it. Why don't you start by "studying" the first law of thermodynamics. Better yet, skip all that, and just Google "Internal Energy of an Ideal Gas". It will get straight to the point...

Cool story bro...

Y u mad?

I really fell bad for you man...

 

[GST with PSI]

completely wrong? How so? Go ahead... I'm listening....

If you think you are right and i am wrong, prove it... Simple as that. If you can't prove that i am wrong what is the point in trying to argue?

Take everything i said, and point out exactly why i am wrong. I know for a fact that you wont be able to.

Ok you are wrong, and as requested I'll take everything you said, break it down and explain how you are wrong.

Mass is not a changing variable effecting your turbo, like say for example, temperature is. Maybe you have heard of the concept of conservation of mass in middle school or something? If so, you know that an objects mass doesn't get created or destroyed. Mass and velocity are NOT what make your turbo work. If you don't believe me, NASA can explain this to you. There are pictures and everything:Conservation of Mass Make sure you pay close attention to the fluid dynamics part.

It's the mass and velocity of the gasses flowing

Ummmm, no it's not. Air mass is a measurement needed so the engine can deliver the correct fuel mass to the engine. Air density is the variable. As air flow (pressure) increases, density goes up. Air density is mass per unit volume. The significant change in air density entering you engine is largely changed due to the intake pressure created by your turbocharger. Air mass is not the reason why the turbine actually moves. Your turbo works because of pressure drop across the turbine as I told you before. Without pressure drop, there would be no flow or velocity. The drop in pressure creates flow. If you still can't understand how you are wrong, I don't know how else to explain it to you. Maybe you should just accept the fact that you wrong if that's the case.

at 5k rpm full load you have max air and max fuel combusting.

So this happens at 5k on every car guaranteed no matter what? Hell, I have been tuning my car all along without knowing this? This makes things much easier though. Thanks!

much higher mass and velocity of gasses flowing through the turbo.

Nope, mass is not getting "higher" and velocity is only a byproduct of a pressure drop across the turbine.

You should take some time to read and understand how a turbo system works. You dont want to be that guy who talks about his car and everyone around goes like this

...this is you ^^^


Now, before you say anything else dumb like "I need to study" or "I'm misinformed" or "open a thread if you want to debate this" Why don't you tell me how this works then? Actually, unless your next post is going to disprove theories and laws of science that have been known for decades, don't wast my or anyone else's time with another BS post. Although just for my amusement, I would love for you to explain how turbos actually work in your world.

 

[avefenix]

so umm how does a turbo work???


, sorry gentleman i had to throw that in

 

[GST with PSI]

so umm how does a turbo work???

Wizardry, mainly...

 

[1983gsp]

Allshallperish.......you sir, are a blooming idiot.

Never mind...I see you have a little red chicklet ....please continue

 

[ShadyGST]

Seriously moderators?

This thread has become waaaay out of hand. I think both parties involved should get rep taken away.

Just because some is a supporting member, does this mean they can act any way they want?

And Allshallpershish... wow... just, wow....

 

[cartz-snopro]

previous owner of my car said the turbo was bad since it didnt make boost, had a pinch in the boost gauge line !!!! thing pulled like a freight train