T4 Guys (BB CHRA)
 

http://www.atpturbo.com/Merchant2/me...egory_Code=GTB

Anyone running one of the new T4 BB CHRA's? Pretty pricey...but I'm looking for a little more zing, and why not run water thru the CHRA?


Garrett ball bearing CHRA, 60-1 compressor wheel (for T04S housing), P-trim turbine wheel. Fully assembled and balanced backplate. Just swap end housings and go. Uses ATP-OIL-021 oil inlet fitting. T3/4 drain flange. Coolant in/out required (14mm threads - same as GT series ball bearing). Nice "drop-in" replacement for an exisiting T series turbo using this same wheel combination.

hmmmm. . . might be interesting. . . :D

If you're going to goto a BB CHRA, why not atleast run a GT wheel? A lot of the reason why the BB turbos are more responsive is because of better wheel material and technology, its not just the CHRA...

We can set you up with something like that to go with a stardard T4 turbine trim; P Q etc

The issue I have is that once you have a non BB turbo that works for you, you'd almost have to start over. Not completely but somewhat in regards to how it'll effectively run on your motor.

What do you mean? If you change anything in your system you're going to have to retune, not just a turbo. I'm assuming thats what you mean by starting over.

What I mentioned to Dubulup was a BB gt35R with a standard P trim turbine/T4 housing so nothing else physically exhaust/turbo cooling would need to be changed. Again I'm not sure if you're refering to starting over because of T3 vs T4 footprints etc...

i have been trying to find out if i could "upgrade" my t4 60-1 to something with a gt wheel. am i reading this right? can you simply upgrade the wheel, and keep the to4s housing i have on my turbo currently?

id definately like to hear more info on this!!!

Yes we could do something like that for you, its however going to require a rebuild to put a GT comp wheel in. Honestly we can do just about any combo, any custom turbos etc, all it takes is MONEY.

i had been looking at replacing my standard journal bearing chra with a gtr chra. is that do-able? or is it even cost effective? maybe we should take this to pms?

Hmm.. I've got a t04 as well. It has .70 compressor and .96 exhaust undivided with p trim. Regular 360* thrust bearing. What are my options and how much $?

I believe the compressor housing for a 60-1 would have to be machined to fit a GT wheel in...or maybe it's the other way, the opening is all ready too big?

I don't think you can swap between the too...although, I'm no expert but that's why I think garrett came out with the BB CHRA I listed up top.

That is the part that sucks about doing custom turbos like this, ones off get expensive machining the compressor housings/backplates ETC.

In all honesty I usually just sell a complete new turbo if you want a hybrid between GT and T series, this way we can use the GT comp housings that match depending on the frame.

I'm personally not the one machining this stuff, I'm not the only one that works here...

hehe, GET OF THE COMPUTER AND GET TO WORK. . . LACKY!!!!:D

anyways, heres the price break-up.

assuming i have a 60-1/to4s (which i do), i could get the BB chra for $935, and be done with it. that turbo is rated at 550hp (no, i dont have dillusions of grandure, and i know what its rating is meant toward). the whole she-bang in journal bearing form can be had for $880. now, i cant remember what i paid for mine (mostly, because it was part of a kit, then upgraded to what i have now), but looking at the upgrade path you end up spending over $1800 for a BB 60-1. WOW!!! gt35r anyone???? hehe.

of course, that is all somewhat negated, because the turbo/car SHOULD have been in use the entire time. so, you played with what you paid for, and then comes along a nice little "drop-in" upgrade to make life a little MORE fun w/o MAJOR expense. . . to include tuning.

i think this isnt such a bad idea for someone somewhat budget minded. . . whos had the turbo for a while, and is just looking for a little something different. what to do with the swapped out chra is the question, though. :D

Just so it is clear most GT wheels are not available as a stand alone part. They were for awhile, but if you go and try to order say a 35R compressor wheel or turbine wheel now, they are no longer listed separately by garrett. Just a heads up.

-S-

good info^^^^^^^

so, does anybody know what kind of difference this ball-bearing chra has when compared to a GTR chra?

Hmmm, stick that t04B 60-1 BB CHRA w/ "P" trim in a bored S5 TII exhaust housing w/ HiFi comp housing and you have a nice "cheap" GT35R killer :) Still gotta fab some oil/water line adapters too.

Do they offer a clip when you order it? My current stock hybrid has "P" trim w/ 15 deg clip as it choked w/ 7 deg clip

Or does the easier to spin BB shaft reduce low rpm choke effect?

That is certainly true for piston engines, but we don't know how it relates to rotaries. It may turn out the BB t04 wheels work better for the rotary- they haven't been out long enough to know.

The GTQ wheels were computer modeled for smooth flowing piston engines 4 cyl and up using modern tuned length collected manifolds.

Last time a turbine wheel was designed specifically for the rotary it looked WAY different than the GTQ. The proprietary "impact" wheel has straight blade section for the major diameter, GTQ looks more curved than old T04.

Though, perhaps w/ the nice long runner exhaust mani in GTQ wheeled kits the rotary flow is smoothed enough GTQ works better than T04 or Impact wheels.

It does appear the short runner exh mani GT kits don't do nearly as well as the long runner GT kits- this would indicate to me GTQ wheels don't like "impact" as the old T04 turbos don't seem quite as sensitive to runner length.

Anyways, just speculation. I hope the GTQ wheels are a hot ticket on rotary, I have a plain bearing GT that looks to have the GT40 exhaust wheel and 35R compressor wheel (GT37 out of Ford 6.0).