[INFO] Before & After GCG Turbo Hi-Flow

[wreckedhead]

Gcg = Rip Off

[MYSTR33]

Gcg = Rip Off

can anyone recommend any other places that is reliable and do a good reuilt?

[wreckedhead]

garett arnt bad in chipping norton

[discopotato03]

I always wanted to see a GCG Highflow from the compressor and turbine perspective . I don't suppose you could let me see (please please please) some pictures of it with the covers off .

I suspect it uses a 76 trim TA34 turbine , and that compressor just could be what Garrett (Chipping Norton) called the "T3 highflow Wheel" . It was standard on the Buick Grand National and off the top of my head the part no was 299-4 . I once had the map for it so have to have a look .

I'm thinking XTR turbos are rebuildable using Garrett plain bearing style turbines and compressors so not necessarily getting the latest aero technology with them . At least they fit straight in ......................

[mr_rbman]

can anyone recommend any other places that is reliable and do a good reuilt?

ATS (Adeliade Turbo Services) here in Adelaide are very good and have a very good reputation

[4door_Sleeper]

mr-rbman - I asked around a month ago and whilst there was no problem with the quality of the work done by ATS, the power results were not as good. (opinions from a few dyno shops around adelaide)

As I said befor, at the same PSI I am getting about a 20% improvement in power (so I guess about a 20% improvement in flow)

[dangerous_daveo]

mr-rbman - I asked around a month ago and whilst there was no problem with the quality of the work done by ATS, the power results were not as good. (opinions from a few dyno shops around adelaide)  

As I said befor, at the same PSI I am getting about a 20% improvement in power (so I guess about a 20% improvement in flow)

It could also be that the air that is flowing is cooler, that combined with the lager size makes your 20%.

[4door_Sleeper]

but according to Boyles law (pv=nkt) pressure is proportional to temperature, so in the absence of any other changes in the system (ie same intercooler, pipes, and same pressure of 14psi) then the temp shouldnt be any different.

[discopotato03]

Ah yes ATS ..........

They built that bastard hybrid for that wacko importer over there that can't keep his tongue in his head . For that "drift unregistered RB20DET One Eight Via ? "

It used the turbine from a series V RX7 and a -24 or 25 T04B compressor in bored out (bastardised) RB25DET Hitachi housings , actually the turbine housing was VG30 . Someone I know coppied it and it was a surging pig . On ya Bill .

[mr_rbman]

Ah yes ATS ..........

They built that bastard hybrid for that wacko  importer over there that can't keep his tongue in his head . For that "drift unregistered RB20DET One Eight Via ? "

It used the turbine from a series V RX7 and a -24 or 25 T04B compressor in bored out (bastardised) RB25DET Hitachi housings , actually the turbine housing was VG30 . Someone I know coppied it and it was a surging pig . On ya Bill .

r u baggin ATS or what?

[Cameron_Datto]

It used the turbine from a series V RX7 and a -24 or 25 T04B compressor

Disco potato .. How did you find out what compressor wheel ATS used ? I remember Reading of this Turbo years Back now in Zoom .. I always wondered what the spec of the COMPRESSOR wheel was .. WHEN you say 24 or 25 ,What do you mean as i havent seen a map on that wheel from memory ..Have you got any info on that map ?

I made up a turbo using the same specs but used a Different compressor wheel due to it going on a 4 cylinder engine ,, but i used the RX7 core with the RB25 intake and exhaust housings .. I did try a Vg30 EX housing but it was to big for a 4 cylinder ..

[MYSTR33]

wat prices are they offring mr_rbman? any ideas?

[|PRESA|]

Any places in Melb that are good with HI-flows? Avo turbo wouldn't do a hi-flow and recommended me an upgrade at well over $2k

I heard of some place called ATP?

[juicen]

I always wanted to see a GCG Highflow from the compressor and turbine perspective . I don't suppose you could let me see (please please please) some pictures of it with the covers off .

sorry mate, i'm not mechanically minded enuf to be doing that

[mjfawke]

but according to Boyles law (pv=nkt) pressure is proportional to temperature, so in the absence of any other changes in the system (ie same intercooler, pipes, and same pressure of 14psi) then the temp shouldnt be any different.

Yes, but that's at 100% efficiency. Turbo's generally peak out at around 80% efficiency, and if your flow/pressure ratio is at a point where the turbine is only around 60% efficient, it will heat the air more. Which is why we should always get the compressor maps with a turbo.

[sproosy]

can anyone recommend any other places that is reliable and do a good reuilt?

Well some people say just jap is a rip off, but the prices here for a high flowed RB25/RB20 turbo looks cheap than GCG....

http://www.justjap.com/new_forced.htm

[Sydneykid]

That's a ball bearing hi flow, ie; it uses a ball bearing core with water cooling. You can get a plain bearing hi flow job done much cheaper. Personally I see no reason to replace a ball bearing water cooled turbo with a plain bearing oil cooled one. As for power, we have 265 rwkw (355 rwhp) out of a GCG hi flow on an R34GTT and that's pretty damn close to its rated 450 bhp. Plus it makes more power EVERYWHERE than it did when standard.

So I don't feel ripped off, in fact I am using another GCG ball bearing hi flow on the Stagea. I had plenty of other choices, but I don't feel there is a better turbo for my requirements. For $1950 (all up, no more to pay) and half a days work (just bolting and unbolting, no fabrication required) I can't think of better value for my money or time spent.

PS; 265 rwkw and it looks standard, never likely to fail a rego check at any level.

[discopotato03]

Camereon-Datto , I spoke to him at the time and not surprisingly he wouldn't say . The article said it used a T04E wheel which was a crock a shite . Have you ever seen a 70mm eight bladed E wheel ? no one else has either inc Garrett .

The fellow I knew looked very closely at the compresor cover inlet (picture), measured up the snout of one he had and opted for the -24 T04B wheel . He was certain Bill used the slightly larger trim -25 T04B wheel .

Quitly frankly it wouldn't matter which eight blade B wheel was used , they're all useless for petrol engines . The problem is they were designed to move lots of air (for their size) at low to medium shaft speeds hence lots of blades . The newbies try to use them with turbines designed to drive six bladed wheels at higher speeds . Innitially this causes lag and when it finally gets going it pumps too much air for medium engine speeds and starts to surge .

To have any hope of working this needed one of the six bladed 70mm T04B wheels of which the H trim was one , but there was also one of similar size to the V trim ................... Just dug out the old paper work :

T04B 8 Blade wheels commonly used .

409179-0021 70x48.36 = 48 trim . Known as S trim

409179-0022 70x49.50 = 50 trim

409179-0023 70x51.61

409179-0024 70x54.00

409179-0025 70x55.37 = 63 trim . Known as V trim

Note the dash 24 and 25 , the last two above .

T04B 6 Blade wheels

409826-0006 70x48.35 = 48 trim

409826-0012 70x52.85 = 57 trim

409826-0014 70x55.30 = 62 trim

409826-0015 70x58.40 = 70 trim . Known as H trim .

I only know of the last two , dash 14 and 15

being used in place of the 8 blade variety .

I did hear Turbo Dynamics in Sydney liked the six blade versions in their hybrids .

I vaguely remember someone in Zoom or HPI did an article on replacing the twin turbos on the series 6 RX7 with a single to get around reliability probs with the twins . It involved fitting basically a turbo/manifold off a series 4 or 5 RX7 and the , drum roll ....... "Trade Secret" we won't tell you compressor wheel , looked very like one of the six bladed T04B's .

[Cameron_Datto]

Disco Potato.. Thats Excellent info ,,, i also studied the Pic and thought some thing didnt add up on what they wrote ,, What you have said about the wheel trims makes sense as that is why they made it work with the larger exhaust housing ... I thought i might have a Been a V trim as i also read the about the SINGLE turbo up grade on the RX7 engine .. and found that Horse POWER in a BOX was selling a HI FLOW Turbo Rx7 ..which i guessed Might have come from ATS ,, They Said the RX7 turbo used a V trim wheel which was very responsive .. .. ATS also have another COMPRESSOR wheel combo with the RX7 turbo made for 1.8 and 2ltr 4cylinder engines which iam yet to find out some info ,, but i am guessing its a small to4 E trim wheel .. but they used a .58 A/r on the exhaust side .. which seems rare to me ..it was a t3 pattern ,, I thought that might a been a Mazda 12a turbo EX housing..

[discopotato03]

That RX7 hybrid used a six blade wheel so wouldn't be a V trim which has eight . The -14 or 2nd last 6 blade shown is very close dimensionally to a V trim .

The E wheels have two distinct blade forms , earlier types are layed back from the wheel hub sort of cropped . The later type have a large spot face for the lock nut to bear on and the blades are not level with each other ie 180 deg appart looking into the inducer side . Safe bet Bill used -14 T04B , cheap easy to get and minimul machine work . T04B's are a flat backed wheel where T04E's are a shallow tulip shape , deeper through in section needing a longer turbine shaft .

That article mentioned a map very similar to the -14 / -15 maps ie long and low to the right meaning wide range at relativly low pressure ratios - just the thing for OEM power output for the era .