Q about t3/t4 57 trim

[ZSPTurbo]

If it was running say.... 23 psi, when would it hit full boost? like, 4000 rpm? from a dead stop, like on a dyno run or something.

 

[1969MIB]

with what exhaust a/r and what stage compressor wheel. The typical combo would be .63 a/r and a stage 3 wheel and your looking at maybe 3750 rpm, not bad at all

 

[DSMJim]

what about with a big spearco fmic like the 2-216 core, will that affect spool times on the turbo at all? I was thinking about the same turbo but a 50 compressor not 57 but the same .63 a/r stage 3.

Any opinions on that? I dont wanna lose my quick spool of the t-25 anymore than I have to.

 

[1969MIB]

thats a very good turbo, and the spool will not be bad at all, itmight bother you for all of 58 hours and then you'll never want a smaller turbo again. trust me on this. Intercoolers do not add very muchlag at all.

 

[ZSPTurbo]

Originally posted by 1969MIB
with what exhaust a/r and what stage compressor wheel. The typical combo would be .63 a/r and a stage 3 wheel and your looking at maybe 3750 rpm, not bad at all

it would hit full boost at 3750? really?

T3/T4, 57 trim stage 3 wheel, .63 A/R

 

[L2RTSiAWD]

Originally posted by ZSPTurbo


it would hit full boost at 3750? really?

T3/T4, 57 trim stage 3 wheel, .63 A/R

For 23psi. Not even. Maybe 15psi@3750.

Swtiching to a 57trim turbo is not going to spool anything like the t-25. if you want that kind of spool may as well switch to some type of big28.

 

[ZSPTurbo]

Originally posted by L2RTSiAWD


For 23psi. Not even. Maybe 15psi@3750.

Swtiching to a 57trim turbo is not going to spool anything like the t-25. if you want that kind of spool may as well switch to some type of big28.

well then, for the setup that I said, when would it hit full boost?

 

[L2RTSiAWD]

Maybe 4200,4300 for 23psi.

 

[ZSPTurbo]

thank you very much.

 

[waterdeep]

I agree with L2R...
But I also contest that anyone whom is thinking of going garret 57trim to check out the flow rates/maps of that trim compared to a 50trim wheel (it is much more efficient)... although it is usually a little more expensive it is worth it IMO!

 

[ZSPTurbo]

Originally posted by waterdeep
I agree with L2R...
But I also contest that anyone whom is thinking of going garret 57trim to check out the flow rates/maps of that trim compared to a 50trim wheel (it is much more efficient)... although it is usually a little more expensive it is worth it IMO!

oh, I have already decided to go with the 50 trim and .48, I was jut curious about this turbo.

 

[waterdeep]

I have been in a modded 2g gst with the stock motor with a 50trim, .63ar stage3 and it got 18psi @3800rpm

 

[L2RTSiAWD]

Ya a 50-trim can get 20psi@4000

 

[ZSPTurbo]

wow, I ran the equations on the compressor map, and this definatly isnt the turbo you want for 23 psi:

 

[DSMJim]

wow how did you do that to lay the line over the map? I wanna do that with a 50 on the same engine with a .63 vs. 43 exhaust a/r

 

[ZSPTurbo]

Originally posted by DSMJim
wow how did you do that to lay the line over the map? I wanna do that with a 50 on the same engine with a .63 vs. 43 exhaust a/r

well, its a couple things. its all in this one special equation though. IM me and Ill try to explain it. im me, zspturbo

 

[ZSPTurbo]

and you mean .63 vs .48, right?

 

[ZSPTurbo]

gtg, Ill just plop the equasion down and explain it tomorrow.

Litres x 61(CID) x RPM x .5 x Volumetric Efficiency
------------------------------------------------- = Result x Pressure Ratio = CFM Flow x 0.0756 = Pounds of air per Minute ( Lb / Min )
1728

ok, that didnt come out good, copy and paste it in word or something.

its more like this:

Litres x 61(CID) x RPM x .5 x Volumetric Efficiency

divided by 1728

x desired pressure ratio

x.0728

equals lbs/min.