Why would anyone put a bigger turbo on when the factory turbo is regulated by a waste gate anyways? In my head I see a different waste gate giving me more boost and then more thrust. Am I wrong?

"Donny was a good bowler, and as a surfer explored the beaches of southern
California from Redondo to Calabassos.
In your wisdom you took him, Lord. As you took so many bright flowering
young men, at Khe San, and Lan Doc, and HILL 364!" Walter Soapcheck.

 

it's all about compressor efficiency... you get to a point where more boost just makes more heat, not more power

Forrest

 

When a different turbo is put in do people play with their waste gate? I want to know the benefits of an aftermarket turbo. What's the point?

 

stock turbo is only good for about 35-36psi... if you want more power, you need more boost. if you want more boost, you need a different compressor that is efficient at a different pressure ratio.

and yes, you'll want to adjust your wastegate to get your boost level set where you want it.

Forrest

 

More boost doesn’t automatically mean more power. More air flow is what is needed. If you compress air it gets hot, hot air is not good. If your turbo can flow more air at the same boost you will get more power (if you have enough fuel). Think of a 1/2 inch garden hose, if you put a nozzle on it you will get a lot more pressure (think boost) but no more water, If you have a 1 inch water hose you can get a lot more water (think air flow) but with less pressure.

 

well... yes... but that's not what we're talking about here...

the only way to get more flow is cylinder head porting and or a camshaft...

so in order to get more air MASS in there, we have to furthur pressurize the air to fit it in the same little hole... with pressure comes heat... and different compressors are efficient at different mass and pressure levels...

cooler air takes up less space... so with a more efficient compressor, you can have more oxygen at 38psi than you would with a stock turbo at 45psi... for example... you have MORE oxygen and a cooler charge temp, which equates to lower EGT's and more power.

we are not interested in CFM, we are interested in lbs/min

Forrest

 

So a different turbo can put more pressure in there without getting the air hot?

 

yup

 

well not nessary more pressure, but more lbs per minute

 

If I substituted the word mass for the word flow would my explanation make more sense or am I totally confused???

More boost doesn’t automatically mean more power. More air MASS is what is needed. If you compress air it gets hot, hot air is not good. If your turbo can make more air MASS at the same boost you will get more power (if you have enough fuel). Think of a 1/2 inch garden hose, if you put a nozzle on it you will get a lot more pressure (think boost) but no more water, If you have a 1 inch water hose you can get a lot more water (think air MASS) but with less pressure.

Does this make sense now?

 

I see what you're saying, and a larger turbine side will increase flow to an extent, but we're talking about a compressable gas... the water analogy seems a little tangent to me.

Forrest

 

Not to complicate things,BUT you also have to look at how much pressure it takes to make the cool air and at what rpm it comes in at. I went from the hybrid to the straight 40 which is stock and really don't like the way the 40 spools. The hybrid was right there all the time and the 40 is kinda lazy. I'm not trying to confuse KORNY but it seems tuff to get what you really want with airflow and spool and exhaust temps. Sorry to ramble!

 

twins = cake that you can have and eat

 

Ya, I know a frickin clone would sure help me out for a couple of months. I was thinking about the twins coming home tonight since it got in the 80's around here. The poor old 97 doesn't like hot weather! Korney, if ya don't add fuel a bigger turbo probably won't be much of a benefit, but ya could always try.