Factory Borg Warner S300G

[TJarecke]

The p/n I have is 174430

 

[Diesel Freak]

I do not have the part number for that particular turbo assembly



I have



167338

169417

168824

168823

 

[Diesel Freak]

I can not even fint that part number on the Borg Warner website.



http://www.turbodriven.com/en/productsearch/index.asp

 

[TJarecke]

This is a p/n from dieselsupply.net

I called them and I couldn't talk to the guy I wanted to but the other guy told us what he knew and a price. He said it was a S300G.

I don't know why their number would be different.

 

[OPoole]

The p/n I have is 174430

That turbo has a very small comp housing and a 57mm wheel with a . 80 a/r exhaust.

 

[Hohn]

A bit off-topic, but maybe not (??) - what exactly is a/r ratio? 0. 7, 0. 8, etc? The higher the ratio, the faster the "quick spool"? I'm just curious because some people quote this ratio instead of exhaust housing size per se. Probably since 14 cm (for example) means different things to different turbo manufacturers?

I know it has something to do with housing radius and such...

A/R ratio: A ratio of the cross-sectional AREA of the turbine housing to the RADIUS as measured by the length of the line extended from the center of the housing's cross section to the center of the turbine.

A/R expresses turbine housing size relative to a specific location in the housing.

A/R can account for different turbine wheel sizes (the RADIUS part), while simply stating the area alone does not.


For example, Holset offers a 16cm housing for the HX35 and well as the HX40. Do the flow the same?? NOPE! The HX40 has a larger turbine wheel than the '35 does, which increases the "radius" part.

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Ironically, this means means that the HX40 with its larger pinwheel would have a LOWER A/R ratio (i. e. , more R for the same 16cm A).


What does this tell you about flow? It depends on whether the turbine housing or turbine wheel presents the main restriction to flow.

If the housing itself is substantially more restrictive, then a larger A/R should give you an appreciable increase in flow.

Conversely, if the WHEEL itself is the main restriction (say, like a 21cm housing on an H1C), then it's quite possible that you could get more flow from a LOWER A/R on a bigger turbo.


Don't think of A/R in terms of comparing one turbo to another, as it's possible have more flow from either a lower OR a higher A/R comparing one turbo to another.


Rather, think of A/R as a location on a spectrum with one end being max spool and terrible flow (relative to turbine's potential flow) and the other end being the maximum realized potential turbine flow but terrible lag.


Do NOT use A/R to compare one turbo to another-- just a single turbo's behavior within a range of options.


Cliff, correct me if I'm wrong.

Justin

 

[RonA]

I took my 62/. 7 off recently. I'm going to a different turbo. City Diesel is where I got it. Been gated at 24psi in my twins for about 2k miles. Great upgrade from a 35. Sorry for hijack.

 

[TJarecke]

Why are you removing it?



If I were going to buy an off the shelf S300G do you guys have a recomendation on which one to go with and the p/n? Thanks for all of the replies on the topic.

 

[Diesel Freak]

A/R ratio: A ratio of the cross-sectional AREA of the turbine housing to the RADIUS as measured by the length of the line extended from the center of the housing's cross section to the center of the turbine.



A/R expresses turbine housing size relative to a specific location in the housing.



A/R can account for different turbine wheel sizes (the RADIUS part), while simply stating the area alone does not.





For example, Holset offers a 16cm housing for the HX35 and well as the HX40. Do the flow the same?? NOPE! The HX40 has a larger turbine wheel than the '35 does, which increases the "radius" part.



#ad




Ironically, this means means that the HX40 with its larger pinwheel would have a LOWER A/R ratio (i. e. , more R for the same 16cm A).





What does this tell you about flow? It depends on whether the turbine housing or turbine wheel presents the main restriction to flow.



If the housing itself is substantially more restrictive, then a larger A/R should give you an appreciable increase in flow.



Conversely, if the WHEEL itself is the main restriction (say, like a 21cm housing on an H1C), then it's quite possible that you could get more flow from a LOWER A/R on a bigger turbo.





Don't think of A/R in terms of comparing one turbo to another, as it's possible have more flow from either a lower OR a higher A/R comparing one turbo to another.





Rather, think of A/R as a location on a spectrum with one end being max spool and terrible flow (relative to turbine's potential flow) and the other end being the maximum realized potential turbine flow but terrible lag.





Do NOT use A/R to compare one turbo to another-- just a single turbo's behavior within a range of options.





Cliff, correct me if I'm wrong.



Justin

looks feasable



A/R is useless without turbine size

 

[2broke2smoke]

EXCELLENT POST HOHN!!



cleared up another misconception that i had



thanks

 

[RCenters]

http://www.rbracing-rsr.com/turbotech.html



some good reading and calculators