Just as the title states let get some info on Turbos and stages of turbos built up for reference and a quick guide for the DIY guys.


Post any turbo info you have that would relate back to the Tc and picking out a turbo that's right for your needs.

 

This is where Paul or Joe chime in and blow everyone away

 

Isn't there a stick in F/I detailing all the turbo packages available?

 

The better information would be horsepower potential. For instance something like:

ZPI 16G-350whp
Greddy 18G-360whp
20G-400whp
T3T4 Tubonetics-400whp
GT30-500whp
GT35R-600whp

 

Not when you look at the Turbos A/R's You can have a t3/t4 with infinate options on A/R's and that is how I want this post to look at. I want people to know ie:

A t3/t4 with a .48trim willl reach full boost at this rpm range on the Tc and so on....

 

A/R is how the turbo responds to throttle and overall power performance. Larger A/Rs are geared toward some lag, but much more power oriented while smaller A/Rs are geared toward throttle response and less power.

i.e.

.48-daily driven street car
.63-street car, more radical, more power
.82-drag car, built motor

These are the most common T3 turbines.

Don't forget that the gear of the car also depends on when the turbo will spool.

 

Paul... I knew you got what I was after here. I am going to be calling the shop here in about thirty cool with you?

 

There are too many variables. Just an exhaust can make a 500-1000rpm difference in spool-up. Most people are looking for power potential I would think. Most of the kids here don't know what a/r is...

 

Cool with me.

 

/\/\ Here's a wonderful noob question:


What does A/R stand for anyways, and WHAT EXACTLY makes a .48 a/r different from .60 a/r, from .80 a/r, etc...... Characteristic of the turbine???

 

^^^ I know hence why we are talking about A/R's^^^^

 

Power potential is all great when we are standing around comparing how big yours is to the next guy. But its not about how much you have but where the power is avaliable. What good is a turbo that makes enough flow to get 500whp if that isnt acheived untill 6000rpms....?

 

A/R is really a ratio of area/radius of the turbine housing. It's like a ice cream cone wrapped around a snail shell. The hole at the end is the "area" hence the "A" in A/R. The size of it determines the gas velocity. The "R" is the distance from the center section of the cone to the center of the turbine shaft.

 

Not sure if you have seen this site before but it has a ton of good info to read and learn from.. Make sure you read 101- 103.. http://www.turbobygarrett.com/turbob...ch_center.html

 

.63 AR for the 500whp build

 

With a 2.4 engine, spoolup isn't much of an issue until you hit the GT35R. Any smaller turbo will be fine on our car. Any turbo that spools up 3500rpms or less will be fine on our cars, since that's where the RPMs drop to after a shift.

 

Damn! I get home from work and see this thread that I love so much to speak of, but never want to flood the forums haha...

Paul beat me to it... So I'll throw in some tid-bits.

Where do you want to be making your power? Take into account your desired PSI, displacement, rpms, and dare I say intake and exhaust profiles? So much goes into engineering of the "perfect turbo".

Here's the truth: There is no such thing as a perfect turbo! All you can do is match the turbo the best of your specific needs. If you want throttle response (IE, daily driver or atuo-x) then you need something with a .48 or even slightly smaller. It'll make great torque, but taper off as rpms go up. This is more appearent as you run higher boost levels.

The next step is moderate power. This is where your .62-.68 turbo ARs are ideal. They're great for boost levels between 12-24psi, at a max RPM of about 7000 if you want to be highly efficient. When extreme RPMS or boost levels are run, you want to consider ARs in the mid 70s to even a .82. This will not FULLY spool until about 4000rpms, and that's only under higher loads. So 4th and 5th gears are the only thing that will improve in performance over a smaller AR turbo. The amount of top end you gain is GREATLY offset by the mid-range and low end you lose. This usually equates to lesser performance, and slower track times.

Now unless you really spend about 6k on a motor, and have thr tranny to support it, .82 ARs just aren't necessary for our platform.

Who cares if the max HP is 300 or 600? At what boost and rpm will it make that kind of power? I can get a T25 to make 240whp but at about 22psi and a LOT of cooling. It's not efficient, and not good for the turbo. Let's not bring up the fact that your motor is gone. A t3/T4 hybrid with the correct AR can make decent power (about 300whp) on a stock motor tC. Sure you can get a faster spooling turbo that makes less power, or a slower spooling turbo that makes more, but it all boils down to what your specific needs are.

Some people buy turbos with intentions of building their motor down the road. How far down the road do you plan on doing this? 3 months? 6 month? Over a year? Our turbos that we use can be customized to whatever you want. If you want to change your exhaust AR but keep that comprressor setup, we can actually sell a different AR section. This saves you money and always gives you the exact performance you need.

Hopefully this all makes sense. I'm somewhat pressed for time so I didn't proof-read it lol. If you guys have questions or comments chyme in, and Paul and I will gladly speak to it.

 

/\/\ Great info Joe.

 

Checking out now. Hopefully this read will last a while, at work and need something to pass the time

 

does anyone know the A/R on the greddy turbo or ones that are interchangeable with it

that way i know if i should put money into this kit or just dump it and move on