Garrett T3? T4?

[Dojo2000]

Is the general consensus a T3 would be too small for the 3.8L? I've searched and haven't found too much info on the regular T3, not T3/T4.

I'm looking at a T3 60 trim .48 A/R
From what I've learned a 60 trim is a somewhat larger T3, correct? I really don't understand A/R, or more specifically, what and how its measured.
<blockquote>quote:</font><hr>A/R
A/R describes a geometric property of all compressor and turbine housings. Increasing compressor A/R optimizes the performance for low boost applications. Changing turbine A/R has many effects. By going to a larger turbine A/R, the turbo comes up on boost at a higher engine speed, the flow capacity of the turbine is increased and less flow is wastegated, there is less engine backpressure, and engine volumetric efficiency is increased resulting in more overall power. <hr></blockquote>

Compressor map I found
http://www.turbofast.com.au/img/t3-60.JPG


I would be happy with less than 7 psi, as long as it could handle the airflow of course. Could you intelligent people enlighten me a little more, please? I'll go read up some more.

[ January 06, 2004: Message edited by: Dojo2000 ]</p>

[Arctc Wolf]

so ur turbo will spool up later w/ a larger a/r, but have better VE and less backpressure. use this, plus a dual ball bearing center section, as well as the newest turbine wheels to have the best of everything, quick spool, high VE, and low backpressure. add on a T4 compressor section and u'll have a nice high boost, high flow turbo.

[Dojo2000]

<blockquote>quote:</font><hr>Originally posted by Arctc Wolf:
add on a T4 compressor section and u'll have a nice high boost, high flow turbo.<hr></blockquote>

Then it will just be a T3/T4 hybrid. I'm asking if a regular T3 will work. I can buy a T3 in good condition fairly cheap, and not spend $600+ on something like a T3/T04E. Thanks for your reply.

[nocutt]

Any T3 or similar spec'd turbo will be too small, especially if you have an M5...most true T3's will have a .48 A/R on the hotside max (generally)...yes they can be bored out but generally you cannot fit a bigger compressor or turbine respectively to take better advantage plus the .48 xhaust housing is just small compared to a .63 housing from a bigger T3!!
You will better off starting with a hybrid t3/t4 with specs like .60 for the cold side and .63 for the hotside...well the trims are really up to you...
HTH!!

[Shane]

my specs are .50 compressor .82 exhaust 57 wheel trim and that combo seems to work well.

[Dojo2000]

So is a T4 too large? T04b 80 compressor trim wheel (thats who its described)

I never planned on installing a turbo, but if I can pick a suitable one up fairly cheap it would be a nice project.

[Dojo2000]

Anybody heard of KKK turbos?

Their K24/K26 hybrids are being compared to the t3/t04

Hotside has .06 a/r , but compressor has .42 a/r
Still too small?

[nocutt]

<blockquote>quote:</font><hr>Originally posted by Dojo2000:
Anybody heard of KKK turbos?

Their K24/K26 hybrids are being compared to the t3/t04

Hotside has .06 a/r , but compressor has .42 a/r
Still too small?<hr></blockquote>

Still too small...we love to stick with garrett because they just offer so much complimentary parts, lol!!
Take a look at the combo shane has provided [img]graemlins/bowdown.gif[/img] ...with an A4 however you WILL always need a higher stall with anything bigger than .63 because the power will not come till about half way of the Rev-band...
HTH!!