turbo
Project 180sx
10-30-2003, 03:53 PM
can someone explain to me what trim and a/r are. please. cause i want to upgrade my t25 to a t3/t4 hybrid but upon looking for the turbo there were more options to the turbo then i knew about. if anyone can help thanks.
i dunno if this is a noob question or not, but if it is im sorry to all of you who hate noobs.
i dunno if this is a noob question or not, but if it is im sorry to all of you who hate noobs.
turbo2nr
10-30-2003, 04:06 PM
ok here we go.
trim and a/r
a/r is the housing of the copressor i believe and the a/r is the size and spacing of the turbine blade(i might have it in reverse tho.) the biga/r with a small trim will get u a quick spoolin turbo but will not have to much top end.. atrim will give you move top end but a bit more lag. i recomend a 67 trim with a 70 a\r for a 1.8-2.0l car.
hope this helped
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trim and a/r
a/r is the housing of the copressor i believe and the a/r is the size and spacing of the turbine blade(i might have it in reverse tho.) the biga/r with a small trim will get u a quick spoolin turbo but will not have to much top end.. atrim will give you move top end but a bit more lag. i recomend a 67 trim with a 70 a\r for a 1.8-2.0l car.
hope this helped
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Project 180sx
10-30-2003, 05:18 PM
a/r is the housing of the compressor and a/r is the size of the spacing of the turbine blade? i think thats a typo, and im still confused cause i dunno which one is supposed to be which. hehe. but i get the concept now, thanks. can someone please clear up for me which does which though. thanks
turbo2nr
10-31-2003, 11:50 AM
trim is the size of the spacing if the turbine blade.
sorrie.. hehe
sorrie.. hehe
Dorikin
11-03-2003, 08:10 PM
Man they need a fuckin standardized turbo nomenclature system lol
TD05, T25, AX728283747272 its all fuckin confusing
TD05, T25, AX728283747272 its all fuckin confusing
R.W.240
11-03-2003, 08:40 PM
Man they need a fuckin standardized turbo nomenclature system lol
:werd:
Turbos Irk Me... (goddamn the word Irk is awsome)
:werd:
Turbos Irk Me... (goddamn the word Irk is awsome)
RalphCare
11-03-2003, 10:35 PM
:werd:
Turbos Irk Me... (goddamn the word Irk is awsome)
the word IRK irks me. infact, it IRKs me so much, that i dont wanna even think of its Irkness, for i will probably be irked by IRK once again if i do.
Turbos Irk Me... (goddamn the word Irk is awsome)
the word IRK irks me. infact, it IRKs me so much, that i dont wanna even think of its Irkness, for i will probably be irked by IRK once again if i do.
DWF Engineering
11-06-2003, 02:58 AM
Trim: when you look at the compressor wheel you'll notice that it has a greater diameter toward the base of the wheel. The large diameter is the "major wheel diameter" and the smaller diameter (at the compressor inlet) is the "minor wheel diameter".
Trim = ((minor wheel diameter/major wheel diameter)^2)(100)
Basically, big trim numbers mean more flow for a certain family of turbo; it alo means more lag. The best thing to do is use a slightly smaller turbo wheel with a slightly larger trim. The big trim/small wheel won't cause as much lag as a small trim/big wheel with the same flow.
A/R: stands for "area ratio"...Imagine a cross section of the turbine (exhaust side) inlet; keep the area of this inlet in mind. Now divide this area by the distance from the center of the turbine wheel to the center of the inlet area. The resulting number will stay constant even as you take cross sections from deeper in the turbine housing, where it tapers down more. A big A/R number will allow the cylinder to empty more completely on the exhaust stroke because of reduced back pressure and so on the intake stroke there is more room for fresh air and fuel. This also helps remove unused heat, stored in the exhaust gas, from the cylinder and then alow the turbo to use this heat to drive the compresor wheel. Needless to say, big A/R = more volumetric, thermal, chemical, and mechanical efficiency. The drawback is that the large A/R REDUCES the speed of the exhaust gas hitting the turbine blades. This in turn INCREASES lag.
Trim = ((minor wheel diameter/major wheel diameter)^2)(100)
Basically, big trim numbers mean more flow for a certain family of turbo; it alo means more lag. The best thing to do is use a slightly smaller turbo wheel with a slightly larger trim. The big trim/small wheel won't cause as much lag as a small trim/big wheel with the same flow.
A/R: stands for "area ratio"...Imagine a cross section of the turbine (exhaust side) inlet; keep the area of this inlet in mind. Now divide this area by the distance from the center of the turbine wheel to the center of the inlet area. The resulting number will stay constant even as you take cross sections from deeper in the turbine housing, where it tapers down more. A big A/R number will allow the cylinder to empty more completely on the exhaust stroke because of reduced back pressure and so on the intake stroke there is more room for fresh air and fuel. This also helps remove unused heat, stored in the exhaust gas, from the cylinder and then alow the turbo to use this heat to drive the compresor wheel. Needless to say, big A/R = more volumetric, thermal, chemical, and mechanical efficiency. The drawback is that the large A/R REDUCES the speed of the exhaust gas hitting the turbine blades. This in turn INCREASES lag.
Dorikin
11-06-2003, 03:01 PM
Good explination!
Thats FAQ worthy
Thats FAQ worthy
Mendari
11-06-2003, 03:09 PM
can someone explain to me what trim and a/r are. please. cause i want to upgrade my t25 to a t3/t4 hybrid but upon looking for the turbo there were more options to the turbo then i knew about. if anyone can help thanks.
i dunno if this is a noob question or not, but if it is im sorry to all of you who hate noobs.
If you didn't take Calculus 3 (Calculus in 3 dimensions ) or Physics 3 or 4 ( Fluids and Waves or Optics, I forget which was which ), this topic will be confusing. Go to the Garrett Turbo website and download their .pdf file.
i dunno if this is a noob question or not, but if it is im sorry to all of you who hate noobs.
If you didn't take Calculus 3 (Calculus in 3 dimensions ) or Physics 3 or 4 ( Fluids and Waves or Optics, I forget which was which ), this topic will be confusing. Go to the Garrett Turbo website and download their .pdf file.
turbo2nr
11-06-2003, 04:54 PM
hey mine was alright also.. i gave him the cliffnotes..lolz good explaination
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