schlot said:FYI....the boost pressure has nothing to do with the size of the turbo.....the size of the turbo is related to CFM.
Also 'stang....is that 1/8 mile stats.....looks odd 6 sec with only 102mph.
Wayne
P.S. Owner of a '84 SVO Mustang
RsxtypeS said:I must be blind, unless this turbo doesnt look like a normal turbo. Where is it in that pic?
doogie said:Endrosed, boost is only pressure, CFM is the volume or air in which the turbo pushes. This is always a mis-understanding. Say a worked 2.0 liter with GT3071 makes 400 hp @ 20 psi at that same psi a GT3582 will make 500 and a GT4093 will do about 600+
ssinstaller said:Wrong.
If you have a properly sized turbo, upgrading to a larger turbo should not make more power(at the same boost levels).
A gt3071 should be able to handle about 25 psi on a 2.0L. Unless you can't reach your target HP at 25 psi there would be no need to upgrade. A gt3582 on a 2.0 would probably spool somewhere around 4500+, that would make for a fun 2500 rpm right before redline(at 30+ psi), it would probably be fun, but I wouldn't want to drive it in traffic. A gt4093 on a 2.0L would be funny as hell, the motor couldn't spool it, even with a shot of n20 you probably still wouldn't spool until 4500+and rpm, have fun on the dragstrip(running 35+ psi), but forget about driving on the street---wheelspin at 6000 rpm(ughdance) (ughdance) .
A turbo that's too small will either not be able to sustain the boost level that you want until your motors redline(that's why our motor doesn't hold boost to redline), and it will be outside of it's peak effiency and will be adding ALOT of heat to the intake air.
A turbo that's too large will not spool fast enough creating a horrible peaky powerband with little useable lowend or midrange power, if is way to large you can have problems with compressor surge which drastically shorten the turbo's life.
That's incorrect. Your motor doesnt hold boost to redline b/c the ECU tapers it off through the factory boost solenoid. You have confused the turbo compressor efficiency map with the compressor size CFM.ssinstaller said:Wrong.
If you have a properly sized turbo, upgrading to a larger turbo should not make more power(at the same boost levels).
A gt3071 should be able to handle about 25 psi on a 2.0L. Unless you can't reach your target HP at 25 psi there would be no need to upgrade. A gt3582 on a 2.0 would probably spool somewhere around 4500+, that would make for a fun 2500 rpm right before redline(at 30+ psi), it would probably be fun, but I wouldn't want to drive it in traffic. A gt4093 on a 2.0L would be funny as hell, the motor couldn't spool it, even with a shot of n20 you probably still wouldn't spool until 4500+and rpm, have fun on the dragstrip(running 35+ psi), but forget about driving on the street---wheelspin at 6000 rpm(ughdance) (ughdance) .
A turbo that's too small will either not be able to sustain the boost level that you want until your motors redline(that's why our motor doesn't hold boost to redline), and it will be outside of it's peak effiency and will be adding ALOT of heat to the intake air.
A turbo that's too large will not spool fast enough creating a horrible peaky powerband with little useable lowend or midrange power, if is way to large you can have problems with compressor surge which drastically shorten the turbo's life.
Those are nice cars, but are they really yours? Looks like you took them off the net from a website, especially the RSX one.doogie said:BTW I do have 2 550+whp 2.0/2.3 street cars with full interior that runs 11's and below.
Stroked 2.3 EVO (Brian Crower) IX gt3582 EMS motec M800
598whp
Built 2002 RSX type S 2.0 liter Turbo PT 67 .68a/r. EMS Hondata Kpro
567 whp
JDM Sam said:Those are nice cars, but are they really yours? Looks like you took them off the net from a website, especially the RSX one.
doogie said:Oh is that so..
The company is Cybernation Motorsport and I am one of the owner's
Have nothing else to prove but look in the forums...you will see.
www.cybernationmotorsports.com
JDM Sam said:Yes, I know about cybernation. You dont know who is who on the internet these days, so I am a bit skeptical.
Not sure who you are directing this to...if it was to me, I didn't say anything related to that.doogie said:Oh and BTW not everyone on here that has alittle technical input is selling somthing...Kapisch?
doogie said:(enguard)
The above statement was a general explanation of CFM compared to boost. I am a tuner and engine builder for over 20 years so the lecture was not a neccessity. My point was CFM. As far as your opinion on turbo sizeing, it all depends on your engines configuration, static compression, and volumetric efficientcy (CFM) of the cylinder head. What EMS will be the tunning device such as a standalone or a flash type sinario.
CFM is determined by Turbo housing (inducer/exducer) and turbine wheel period. That has nothing to do with sizeing, the engine config and desired HP and power curve deterimes that so you have been mis-informed. That is why each of these turbo's has a indiviual rating in lb/min. (CFM). Think about that for and min.
BTW I do have 2 550+whp 2.0/2.3 street cars with full interior that runs 11's and below.
JDM Sam said:That's incorrect. Your motor doesnt hold boost to redline b/c the ECU tapers it off through the factory boost solenoid. You have confused the turbo compressor efficiency map with the compressor size CFM.
http://www.turbobygarrett.com/turbobygarrett/tech_center/turbo_tech102.html
I suggest you go to www.turbobygarrett.com and do some reading.
ssinstaller said:Wrong.
If you have a properly sized turbo, upgrading to a larger turbo should not make more power(at the same boost levels).
A gt3071 should be able to handle about 25 psi on a 2.0L. Unless you can't reach your target HP at 25 psi there would be no need to upgrade. A gt3582 on a 2.0 would probably spool somewhere around 4500+, that would make for a fun 2500 rpm right before redline(at 30+ psi), it would probably be fun, but I wouldn't want to drive it in traffic. A gt4093 on a 2.0L would be funny as hell, the motor couldn't spool it, even with a shot of n20 you probably still wouldn't spool until 4500+and rpm, have fun on the dragstrip(running 35+ psi), but forget about driving on the street---wheelspin at 6000 rpm(ughdance) (ughdance) .
A turbo that's too small will either not be able to sustain the boost level that you want until your motors redline(that's why our motor doesn't hold boost to redline), and it will be outside of it's peak effiency and will be adding ALOT of heat to the intake air.
A turbo that's too large will not spool fast enough creating a horrible peaky powerband with little useable lowend or midrange power, if is way to large you can have problems with compressor surge which drastically shorten the turbo's life.
Thanks but I know how to read a compressor map and do the math. By the way that math is missing correctional factors for elevation and compressor inlet pressure drop from the air intake system for pressure ratio. If you want to get technical that math isn't as accurate as it should be.ssinstaller said:I've read the garrett site. And I've also looked at the compressor map of the K04--it does not have the flow capacity to sustain 15.6 psi to 6500 rpm on our motor. Here is some reading for you:
This is why the ECM drops boost in the upper RPM band--to protect the turbo. No matter what you do it will NEVER efficently support 15.7 PSI at 6500 RPM.
I agree about the part of blowing hot air after the efficiency limit. From what I understand you are saying is that you can't run and hold boost past the efficiency limit which is wrong. You can make it blow hot air as much as you want. Chipped VW's do this all the time on the K03. The negative being it will kill the turbo faster.ssinstaller said:A turbo that's too small will either not be able to sustain the boost level that you want until your motors redline(that's why our motor doesn't hold boost to redline), and it will be outside of it's peak effiency and will be adding ALOT of heat to the intake air.
ANDssinstaller said:If you have a properly sized turbo, upgrading to a larger turbo should not make more power(at the same boost levels).
Take an upgrade from a GT25R to GT28RS. I'd like to see how this wouldn't make more power on a 2.0L 6500 RPM @ 1barssinstaller said:It's vary easy to take your statment to mean that a larger turbo will always make more power, and that's just not true, it may have more flow potential available at a given boost level, but if the motor has no need for that extra flow, the effect will be negligable.