Turbo Tech

[dirtydiesel]

I've been trying to get my head around matching turbo spec to engine spec to allow me to pick a better turbo for my tdi,

I have just about figured out how use the garrett numbering system to get a useable number to compare turbos,

Exhaust wheel diameter X trim = comparison number

But i carn't find any info on how to decipher a IHI number to find out it's trim.

Also on a vgt the trim is adjustable so the comparison number would be a range of numberS, does anyone know how to find the minimum and maximum trim froM the part number?

I have aquired these so far but have no way of id'ing them.

IHI vgt numberd as; VB15, 071105003N, 17201-26011. This looks a little big but without number who knows.

This is a borg warner that looks far more promising size wise, numbered;

6H40-6K682-EA, HB 30007659 00012, 5469 950 0042

[pugwash]

Dan,

Pop over to see Eliot Mansfield at www.mez.co.uk he runs a twin turbo chevy V8 with twin intercoolers and controlled by Megasquirt all built by himself. he has some very very complicated graphs for working out turbo specs and he should be able to help.

jim

[Lara]

IHI looks about right, BW is miles too small,

But to be sure contact IHI or BW and they will send you flow charts for the compressor housings and wheel combinations etc, and the same for the Turbines,

you will be completely confused then, if you are not already

Easier way though is to find something with a similar engine size and characteristic to your aimed result and go for the same unit,

Remember that a turbo only knows how much exhaust you expel and not what your engine size is! (within reason and within our context here) so a 200hp engine will need a turbo sized for 200hp regardless of engine size.

you can usually find info like this from someone like BTN Turbos etc, http://www.btnturbo.com/ download their catalogue with all part numbers etc in bottom right hand corner of home page.

Good luck.

Lara.

[dirtydiesel]

IHI looks about right, BW is miles too small,

The IHI is off a 4.2 100 series cruiser, the BW is the small one off a 4.4 twin turbo v8 diesel rangerover (i think)

The BW is slighty bigger than a stock 300tdi turbo whereas the IHI is over twice the size.

But to be sure contact IHI or BW and they will send you flow charts for the compressor housings and wheel combinations etc, and the same for the Turbines,

you will be completely confused then, if you are not already

I've allready tried BW's technical dept they were unhelpfull to say the least. I haven't tried IHI yet.

I'm not confused as such just feel like i'm dealing with lots of unknowns at the moment.

Easier way though is to find something with a similar engine size and characteristic to your aimed result and go for the same unit,

Whats yours then?

Remember that a turbo only knows how much exhaust you expel and not what your engine size is! (within reason and within our context here) so a 200hp engine will need a turbo sized for 200hp regardless of engine size.

This i understand, but i carn't quite figure out whether the turbo off a larger engine with a similar power output will have more lag on a smaller engine due to the smaller engine flowing less cfm per rpm.

you can usually find info like this from someone like BTN Turbos etc, http://www.btnturbo.com/ download their catalogue with all part numbers etc in bottom right hand corner of home page.

Good luck.

Lara.

Good link, thanks.

[Lara]

Hi,

A VNT exhaust (turbine) housing will always look much bigger than a non VNT turbine from a similar engine. do not try to use that as a guide on the turbine side.

Fine for the compressor.

To gauge it by site you need to compare the flow of the VNT to the flow of the normal turbo with the waste-gate wide open!!! Very hard to do.

Remember though that a diesel producing 200 bhp will (again within reason) need both the same amount of air and will produce the same amount of exhaust gas as any other producing the same power. your 500cc super efficient 200bhp factory race engine will need the same ammount of air as my 5000cc old slugger due to probably more revs and deffinately more efficiency, if you can't get the air into the engine due to it being inefficient then you can't produce power and the exhaust gasses are reduced! Size does not matter, efficiency and the whole package do! Obviously different power curves will dictate a different setup, but not "nesesserily" engine size.

A 5000cc engine that runs at 10% efficiency only consumes 250cc air/rev a 500cc engine at 100@ efficiency consumes the same, and therefore burns the same fuel and produces the same exhust entropy.

Sorry if sounding patronising, not meaning to

My engine uses a modified Garrett 2559v which is about as big as they come for automobile use, I have 258bhp and 430ftlb torque and a big pocket

I would suggest a 2256v would be perfect and should be fine for about 160 to 170 (honest) bhp and Loads of low down torque!

The BTN catalogue will list this turbo and you can pick them up at very reasonable prices. Don't over speed it though as the bearings are rather small.

Lara.

[dollythelw]

not sure if this helps Dan?

compressor maps

[SiWhite]

I've got a 2256 waiting to go on a Tdi - PM me if you need any info.....