Turbo Descriptors Compressor Housings

[B-rice]

ok im looking into purchasing turbo online

i have a few question i didnt understand by their descriptions.

http://powertune.com.au/precision-billet-turbo-6262-cea.html

there options for the "E" Compressor Housing 3inlet and 2 outlet

"S" Compressor Hosuing 4inlet and 2.5outlet

"SP" ported compressor cover 4inlet 2.5 outlet

is the one without the blue line the "SP" ported version also are there any advantages of picking any whether "E","S" or "SP" i have tried searching.If i have missed it may you point me in the right direction just need to make the correct purchase form start avoid sending it back.

[FordyR31]

The SP seems to be the housing with the surge slots. They make it sound good but unless you have comp surge they do nothing, considering they sell the housing without for cheaper, may suggest they don't have this issue. Bigger in and out can only help air flow which is always good a turbo but if you have a 3" intake paipe aleady and don't want to buy a 4"-3" reducer then go with the 3" housing. Unsure how much it will limit power if any.

[discopotato03]

Garrett classify their housings in the T04 range as T04B/E/S .

Back to basics . The real way to classify compressor wheels in laymans terms is by the major or exducer diametre . In recent years the aftermarket has gotten into this nonsensical habit of advertising a compressor wheel by its minor or inducer diametre . Dunno why but probably because this is the diametre you can see when you look into the cold side of a complete turbocharger . Its silly because at a glance you have no idea if its a small family big trim wheel or a big family small trim one .

In the pre GT bush bearing days there was generally a given backplate/compressor wheel major diametre association - for example you generally found 71mm (OD) T04B wheels use with T04B sizes backplates and compressor housings . Same with 76mm T04S wheels with the same family sized backplates and compressor housings .

T04Es came along a bit later and introduced an in between backplate and compressor housing size for a different configuration 76mm OD compressor wheel .

Things changed markedly when Garrett and HKS introduced ball bearing technology and higher speed capable wheels , both sides .

You started to get things like BB GT28s with 60mm OD wheels in T04B sized housings where 60mm T3 compressors previously used T3 housings and backplates .

Another example is GT3071Rs that use T04E comp housings where older tech 71mm compressors had T04B housings .

AFAIK the HKS spec "GT3240R" what the basis of todays GT3582R and the start of 68mm OD compressors in T04S backplates and housings .

If I was the OP I would be trying to find out what the major diameter diametre/OD/exducer diametre (same thing) is of the turbo they are looking at and base the comp housing size off that .

Sometimes these aftermarket turbo mobs will fit housings with packaging in mind and the turbos results can be compromised by this .

Garrett with GT/GTX turbos normally size it like this :

60mm GT/GTX wheel .......T04B comp housing . X wheels and some HKS spec housings are port shrouded .

71mm GT/GTX ................. T04B or E housing .

76mm GT/GTX ................. T04E housing .

82mm GT/GTX ................. T04S housing .

GTX wheels have more blades than GT ones and most if not all should havea port shrouded housing .

Mobs like FP in the US have developed there own CNC machined billet wheels and they sometimes go up a comp family you'd think to cope with the extra airflow from extra blades often spun to higher speeds and boost pressures .

Your call but I like FPs stuff because its often based around Garret GT BB units with alternative compressors and housings .

A .

[B-rice]

Alright thanks fellaz with the comp surge is it a part that can be seperatey bought or i should probably ask the seller if it has one because theres no point of getting the SP if its just a white elephant.