I`m trying to identify a specific Turbo off a `SUBARU - Classic WRX/STi`.

It`s labelled as a TD05H-16G, the tag has the numbers :
14412AA091
49178 06300


If it was from an EVO, the following is used to determine if it`s the small or large TD05.

Quote:

Identify the compressor housing model number. On 16G turbochargers, "TD05" is cast onto the compressor housing in raised print. The compressor model number normally contains further designation, such as "TD05H," which is also a wheel designation, however, the "TD05" designation is required of all MHI 16G turbochargers.


Locate the MHI 16G compressor housing part number. On the compressor housing, opposite the model number, is a ten-digit part number. All MHI 16G turbochargers begin with the prefix "49178," followed by the two digits, "01." These positions are cast in raised raised digits, while the remaining three positions, or suffix, is hand stamped onto the compressor housing. The suffix determines the specific 16G model.

Determine the MHI 16G turbocharger model. The hand-stamped suffix for the different MHI 16G models are the following: "420" and "412" identify the big 16G turbo, "450" identifies the EVO I big 16G, "460" for the EVO II big 16G, "470," identifies the EVO III 16G, while "520" identifies the small 16G.

The problem I`m having is I can`t find the same guide for the Impreza Turbos, externally they are the same, it`s just the wheel sizes that differ.



The Small one has better spool and is much better for my application:


Large compressor map for comparison


Can anyone tell me if the 49178 06300 is a `large` or `small` TD05H-16G please ?

 

Hi,
sorry to hijack your thread, but out of curiosity, when does the TD05 16g small start to spool and reach 1 bar on a 2.0 wrx or sti?

I'm wondering how it compares to the TD04 for spool, i know it will be much better up top, but wondering if it would be the same, or how far off from a TD04 in terms of spool.

Apologies if the map shows the answer, i havent a clue how to read it!

I've subscribed to this thread anyway, could be useful to know the answer to your Q for the future.

 

OK, I`m NO EXPERT, this is all new to me and I`m still learning, so if an expert does come along, I shall defer to him

On a 2.0 Engine, these graphs SHOULD help. I`m only learning myself, so I`m not 100%

There are several variations of the TD04, inc 09, 13, 15, 16,18 & 19. Generally, the larger the number, the more lag, higher the boost is produced and more boost they can efficiently flow. Its why you get more power at the same boost with different Turbos. They are more efficient at moving the air, once you ask too much of them, they just heat the air and don`t really flow anymore, hence them feeling to `run out of breath` at high revs.

Look at this graph.

At the 2.0 line (that`s 1 Bar of boost), the blue line `leaves` the map between 5,500 and 6,000. The Turbo is still producing boost, but it`s very inefficient and called the `Choke Line`. You don`t want to be running one here. However, it is `on the map` below 2,500, which would mean it`d build boost VERY early and is also responsive, with little lag.




The -15

This is only just dropping off the map over 6,500, although the efficiency is dropping off before then, it is still OK. Less of the `island` before 2,500rpm so probably a little later to build boost and a touch laggier.


The -19, which are a rare as hens teeth and found on some Volvo`s.

IMO this would be a great Turbo, still has good low down boost and is well inside the island at 7,000rpm. Finding one and making it fit is a different matter


The -16G SMALL is very similar and it`s why I`m looking for one.

Less boost at lower revs, a bit laggier but HOPEFULLY easier to find. Saying that, I`m struggling to find one, hence this thread


Apologies if the graphs`s aren`t perfect, I made a spreadsheet for my own use, I didn`t plan on sharing the screenshots, so the labels aren`t clear and the colours aren`t easy to distinguish.