Anyone that can read a turbo flow chart please help

[mikejames27]

I have absolutely no clue how to read a chart. I have a built 2.0 and am looking at the BW S372 and I have the flow chart which is.

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Do you think this turbo will hit full boost at or before 6000rpm's? If its full boost at 6k I would be completely happy. Thanks for any help!

 

[JusMX141]

Compressor maps don't tell you anything about spool time, they speak in terms of how much airflow is moved at what boost level. It's sort-of an efficiency chart so you can choose a turbo based on how much boost you're planning on running and how much airflow you want to be moving at that boost level.

Spool time hinges more on turbine housing size and a/r ratio than anything else.

 

[dsm-onster]

I concur.

 

[mikejames27]

So where would 20 pds of boost and 40 pds. of boost plot on this map?

 

[dsm-onster]

At 14.2psia which is common and average

20psi = 2.4PR
40psi = 3.8PR

So what is on the map between those PR numbers? from 30lb/min to over 90lb/min. Or from about 260whp to over 900whp .

That compressor can push up to 83lb/min at 20psi. . .you'll never see that at 20psi with any 4g63 or 4g64 in this lifetime. 90lb/min at 40psi. . . Still very hard to do with a 4g63. But possible. You will have LOTS of rpm, LOTS of cam, top notch SMIM and exhaust manifold. and LOTS of turbine wheel & housing.

. . .So basically it's a big ass compressor.

What's your goal. You should be looking as hard at turbines as compressors. This is only half of the turbo. It takes whole turbos to make power

 

[mikejames27]

Well i would like to be in the low 9's full weight. I know people get into the 9's with smaller turbos but Im FWD. Lots of Honda guys use the Borg Warner S372r with the 1.35 a/r and they range from the 1.8L to the 2.2's with this turbo. They are revving out to about 10k. They have smaller bores and I dont know how their engines spool compared to the 4G63. I stayed 2.0 so I can rev high. Im just .020 over on CP Pistons. Another personal goal that really has no true meaning is I want to put more to the wheels then my Supra did. I hit 743hp and 630tq. on a Greddy T78 with a stock rev limit. Just got to make this car more powerful! There is no point to that in and of itself, but Ive got to do it!

 

[mikejames27]

From what Ive heard the S372 spools 200rpms later than a GT42r and makes about 70 more hp.

 

[dsm-onster]

'From what youve heard' with turbos this big means that you're looking for what someone else will guide to do. At this level, since you've been there, you should know that you are on your own to get the airflow and potential that a turbo can yield.