Spoooolage

[DrBrown]

I have a direct Turbo related question. I dont have a DSM BUT it doesnt really matter pertaining to this question. I am using a garrett T3 (.48 hot/60 cold) and it spools up to my not so big 5 psi around 2300 RPMs and it runs out of juice around 5500 and just wont pull any harder. I love the quick spool up of the .48 turbine. I cant decide whether adding a T4 compressor and impeller would push more air and make the car pull up to say 6500-7k RPM's or if it will still run out of power too soon but push more volume of air just till 5k where it levels off now. My goal is to get more power without having to just crank the boost up. I dont have forged internals capable of 20 psi like you gents do. SO I need to rely on turbo size and efficiency to get my goal. So I guess I need to know if anyone has ever upgraded the cold side of their turbo and got more power and more spooling to higher RPMs? Any info would be truly appreciated because I am trying to get my car done by winter and time is getting shorter. Thanks guys

Dan

 

[loreak]

you could upgrade the compressor and you could gain power but at such a low boost theres only so much you can do, your engine will only take so much air at 5psi and at such a low boost changing compressors isnt going to make as big of an impact because its already not heating up the air as much, and some actually may lose power by going bigger because 5psi is too low of boost and is not in its efficiency range

if your spooling that quick and its a t3, i would say either you have a fairly sized engine, or its not that big of a turbo, you need to tell us what car it is and more info

 

[kpt4321]

Give us information about the car, and specificially, the motor.

Also, we need to know more information about the turbo, specificially the wheels.

....Kyle T.

 

[DrBrown]

T3 AiResearch Turbo (60 cold/48 hot)
1995 Probe GT
Enging: 2.5L V6 24 valve 9.1:1 Compression 140 whp stock

All internals are stock with just the fuel upgrades. Most people in the probe community with turbos dont mess with internals other than sometimes cams. Most people laying down more power than 270 at the wheels have hybrids with 63 exhaust turbines and anywhere from 60-67 sized compressors. Most people with this engine and hybrid t3/t4s' get anywhere from 260-300 whp on less than 9 psi. And judging by my 1/4 times (14.4 @ 97mph) I would think I have around 210 at the wheel, maybe slightly more. But I know this turbo doesnt have enough turbine to keep me pulling past 5k rpms *shrug* So if I were to put something like a t04e compressor/impeller on would it be worse? I mean the spool up time should be the same and technically it will just move more air with the same amount of lag right?

 

[pneumo]

A bigger compressor with the same hotside will increase lag somewhat. It all depends on how big of a wheel you get.

A bigger compressor will allow boost to hold at higher rpm.

For us DSMers, a turbo that spools below 3k rpm is a small turbo. When the 2G first came out one popular turbo upgrade was called a Super 60. Basically, it added a T3 60 trim (which is what you have) compressor onto the stock turbo. It's not a popular upgrade anymore. The T4 60 trim is big, but not the T3. Since you have a 2.5l engine at 5 psi I would say you have a little room to uprade without worrying about running off the botom end of a turbos effciency map.