ok well thats very good to hear....

 

I think that I might switch it up and go with the garrett over the precision

 

I'd imagine something small like this unit would work well http://www.go-autoworks-store.com/gat345tr.html

Can anyone else confirm ?

 

yea i was looking at the t3/t4 want a lower a/r so it spools faster.

 

Sweet, the good thing about the Garrett turbochargers to is that you can rebuild them yourself (within reason) as all the parts are available off the shelf. With Precision you have to send it back to them (only) for a rebuild.

I don't want to sound like i'm knocking Precision, but they just seem cheap and cheerful to me personally. The Garrett stuff seems a lot more robust. I guess the famous saying goes "you get what you pay for".

 

ok so now I am a little confused, from my initial reading on turbos and how they work, i concluded that the area/radius of the turbo will help determine where it spools and where the power is delivered in the power band, so a lower a/r spools quick and has better low to mid end power. But it is restricted up top. Am I correct in this? What does the trim do exactly? The trim is related to the compressor wheel right?

 

I spoke with the go-autoworks guys and they wont be able to give me the garrett turbo in a 4 bolt only a 5 bolt.....which blows, kinda puts a damper on the whole thing

 

That only is part of the equation. One has to look at the A/R in reference to the turbine wheel size that they're actually using. What too many people do is get the smaller A/R for "spooling faster" (it actually just shifts power in the rpm band a bit lower), but actually hurts your higher rpm band. This usually occurs depending upon the turbine side used.

The 45 trim is a nice little piece for something for say, VTEC+Mini, but not for what the OP is trying to use. Stick with the .63A/R because it is the perfect match for our cylinder head cfm flow and the turbine size that's used as the standard "T3/T4" from Garrett (which is a 65mm wheel diameter IIRC).

You have a good number of choices in the 49lbs/min - 52lbs/min range of 260whp for the B-series. I'd stick with those sizes. But there are others outside of the usual 50,57,60 trim that are Garretts and still affordable.

 

ok so i am assuming that the bigger the compressor wheel is directly related to the mm size so a 60 trim is bigger than a 50 trim, thus putting out more lbs/min?

 

Only if the exducer size (wheel diamater itself) is the same, is the trim correlated with the larger size and possibly more lbs/min.

But as a practical matter, only the 75mm wheel diamater of the 50,57, and 60 trims ever mean more power. The difference is only about 20whp between the 3. the characteristics of them are what are different.

Normally "trim" doesn't really matter. You could have a GT3582R that has a 52 trim wheel, and make more lbs/min airflow than that of a 60 trim of a 60-1. Smaller trim, but more lbs/min airflow.

Trim is really a matter of a distance between Inducer and Exducer


From the compressor and turbine wheels


But many people think that it correlates directly with more airflow. It can , but only if the exducer of the wheel is the same. which is the case of the 50,57, and 60 "trim" standard Garrett, which have the same exducer wheel. If the exducer wheel changes, it has little meaning.

 

Understood, so if the exhaust variable which is the exducer changes it can indirectly change the lbs/min no matter what the inducer is. Generally speaking how is that measured? If the exducer gets larger does that mean possibly more or less lbs/min, or is it the other way around?

 

Its measured by the overall size of the compressor wheel, not just one area of it with inducer or exducer only. It also depends upon the shape of the compressor wheel, (straight backwall vs. contoured backwall, or splitter blade design vs. straight single bladed design.) There's not really a silver bullet to it all, but it also isn't a lot of ghosts and magic either; the trick is to get the right combination for the right displacement, volumetric efficiency, and engine demand flow. That's what takes a while to master.

 

yes seems like its very specific, which usually makes it more difficult to learn. Thanks for all the information though...it is helpful. I must say I find this forum much more helpful and less judgemental when you are trying to learn.

 

go-autoworks suggested that I go with the street kit and the precision turbo, but after reading and hearing opinions I really want to go with the Garrett Turbo with a 4 bolt pattern for the downpipe. They offer a garrett turbo in the street kit but only 5 bolt and only in a .48 a/r, which I have revently learned is ok but not ideal for my setup.

So I guess I would have to bump up to the "tuner" kit with come with a garrett turbo in a 4 bolt with a .63 a/r. What do you guys think?

 

Yes. I recommend "tuner" kit.

 

thanks, I think I will order that....Might as well spend the money and do it right.