Jump to content
SAU Community

Recommended Posts

  • Replies 84
  • Created
  • Last Reply

Top Posters In This Topic

Fatz you do have a couple of options here , first is to replace the .50 ARR comp cover with the larger .70 ARR T04E cover and keep the backplate .

Second is to use the larger series T04S cover and backplate (adapter ring) which is what Garrett did with their GT3540R turbocharger .

If your finances are limited go the larger ARR .70 "E" cover . If the sky is your limit go the "S" bits . Also remember that the T04S covers are quite large so make sure there's enough real estate where your turbo lives .

Generally compressor covers are sized around airflow rates or speed . So for a given compressor wheel the larger the Area Radius Ratio the lower the gas speed will be and vice versa . Also the larger it is the less chance it will have of being a choke point at high wheel speeds . Someone did tell me that all else being equal going up in comp cover AR brings the boost on a little later and "hits" harder .

With most Garrett turbos there is a set compressor wheel diameter for each wheel/cover family , ie 60mm wheels T3 covers , 71mm wheels T04B covers , 76mm wheels T04E covers , 82mm wheels T04S covers .

In recent years Garrett started going up a size in cover with some of the GT BB series compressors . I think this is because the comp wheels are mechanically stronger , and and can still pump efficiently at much higher rpm's than the bush bearing has beens . This is a win win situation , the small high speed wheels are compact , cheap to produce and more importantly have less innertia so spool sooner .

Examples of this are the little GT28RS (T04B comp cover) and some of the GT2835R series turbos with 71mm compressors and T04E covers .

The Garrett people inthe US tell me that the up sized cover , and a little extra tip height on the wheel , gives extra pumping capacity and a few more points compressor efficiency .

I can only think of two examples of Garrett turbos that went smaller in cover size , they are the HKS GT2540 and the Ford GT3540R . The 2540 is getting on and was probably an attempt to get a bit more flow and power out of a small series turbo , and a low mount compact (convienent) fit for GTR's .

Its safe to say Ford was not looking for serious performance with the XR6T so a compact and probably cheaper adequate cover got the nod . You can bet they knew people would modify them for performance , so the limited cover capacity may have been intended to limit the performance with the std turbo but not affect the standard state of tune .

Cheers A .

yea just stuck a side pipe on the beast and took it out to the drift day

sadly budget has died in the arse so i will have to putt around for some time until a set of cam gears arrive and the powerfc which is probably about 3 months away

im quite happy with the power but as soon as those cam gears are in hopefull it will bring it on a bit better

if cam gears dont bring it down to 4000rpm with power fc and a decent tune then i will consider the upgrade to external wastegate and a .86 rear housing and combine it with the larger front cover

but hey im happy as a pig in shit at the moment and when i win lotto ill do the next big upgrade

ive also got a rb30 complete engine that will be getting a solid bottom end over the next few years to replace the gtr bottom end when or if it ever goes

yea baby

anyone have some cheap cam gears

pete

  • 5 weeks later...
  • 2 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • If they can dyno them, get them dyno'd, make sure they're not leaking, and if they look okay on the dyno and are performing relatively well, put them in the car.   If they're leaking oil etc, and you feel so inclined, open them up yourself and see what you can do to fix it. The main thing you're trying to do is replace the parts that perish, like seals. You're not attempting to change the valving. You might even be able to find somewhere that has the Tein parts/rebuild kit if you dig hard.
    • Can you also make sure the invoices on the box (And none exist in the boxes) are below our import duty limits... I jest, there's nothing I need to actually purchase and order in. (Unless you can find me a rear diff carrier, brand new, for stupidly cheap, that is for a Toyota Landcruiser, HZJ105R GXL, 2000 year model...)  
    • Murphy strikes again! Nothing at all would have gone wrong if you had the tool kit in the car! You'd have just found the clamp loose the next time you went to touch it...
    • I have been being VERY quiet about what you're alluding to, as it is something that ticks me off... The number of cars from factory that run coil overs is HUGE! Most of them these days do... The other part that annoys me, is people saying "Well all the incabin adjustable suspension is illegal by blah blah blah"... If that's the case, then why can I buy a car brand new that can do it if, FULL STOP in cabin adjustable suspension is illegal...   Also, I could just chuck some aftermarket shocks in my car, throw the stock springs on, after my blue slip, dump my super low springs back in. Same shock and spring style setup... Hell, they could also be the same colour springs etc.     I'm voting, BlueSlipper didn't want to touch the above car for some reason. Whether it be some sort of bias against the car, the owner, them maybe having previously done dodgy shit and now they're being super careful in case they get slapped in the face by the Gumbyment again... Find a new blueslip place.   And can confirm as you had said, yes there are holy bibles of vehicle heights, and all sorts of other suspension stuff. Heck your run of the mill mechanic, and tyre shop has access to all of that stuff. It's how they do wheel alignments...
    • Funny story Heading to Sydney this morning on the HWY there was some slow traffic, so I gave it the beans and midway through my overtaking "power run" I lost all power It seems that I missed a hose clamp,  and the MAF and filter went WiFi To make this more problematic, the little tool kit that lives in the boot, is sitting in the sun room at Goulburn......LOL Luckily for me I found a bit of steel on the side of the road that could be used like a rusty and bent flat head screw driver to tighten it up enough that it got me into Sydney, it is now all tight like a tiger with the aid of a 8mm socket Note to self: Use my brain and double check stuff, and always keep that little tool kit in the car for when I have a brain fart
×
×
  • Create New...