12 psi question... (just curious)

[dficken]

I was reading this post...

http://www.protege5.com/vbb225/showthread.php?s=&threadid=17476

...and was wondering a few things.

From what I have read the p5 and msp engines are the same more or less (besides a injector size and maybe a few other small changes). I was really suprised that the ECU would allow this guy to push 12 psi. Would you be able to do something similar with an MSP ECU in a turbo charged p5 or mp3?

One thing I did find interesting is... at the wheels, he was creating 194.8 torque at 12 psi and the FM kit creates 191.5 torque at 6 psi.

 

[Aricjm15]

thats where the difference in tubo, and intercooler effiecency come to play

I'm sure a P5 or MP3 could run 12psi with an MSP ecu and bigger injectors
but the question is for how long, 9psi blew my brothers engine to s***
I would be really careful if i were that guy, I would not be suprised at all if somewhere in the next few months depending on his driving habits if he ended up killing his engine

 

[Kooldino]

I was reading this post...

http://www.protege5.com/vbb225/showthread.php?s=&threadid=17476

...and was wondering a few things.

From what I have read the p5 and msp engines are the same more or less (besides a injector size and maybe a few other small changes).

Actually, I think the injectors are all 280cc

I was really suprised that the ECU would allow this guy to push 12 psi. Would you be able to do something similar with an MSP ECU in a turbo charged p5 or mp3?

One thing I did find interesting is... at the wheels, he was creating 194.8 torque at 12 psi and the FM kit creates 191.5 torque at 6 psi.

Well, you're comparing apples and oranges. A lot of people make the mistake of comparing psi ratings of different turbos. The T25 on the MSP is much smaller than the T3 on the FM kits, for example. So at the same given psi...let's say X psi, you'll actually be moving different volumes of air between the different turbos due to the different sizes of the turbos.

For example the tires on my car are set to around 35psi of air. The tires on my bike are around 50psi or so. BUT, which tire is actaully holding more air? The car tire of course, just because of the difference in volume. So just know that comparing psi is only good when talking about the same turbo.

So just pulling numbers out of my @ss, I'd probably say that a T25@12psi is probably about the same amount of air (typically measured in CFM...Cubic Feet/Minute) as a T3 at around 9psi. Again, that's just a guess. But I'm just trying to illustrate my point.

But let's pretend I'm right, and 12psi on the T25 is about the same as 9psi on a T3. The guys who ran 9psi on the T3 ran into engine problems. Why? Fuel and ignition timing management.

So to answer your question, yes, i BELIEVE it can be done, IF managed properly.

 

[perfworks]

Re: Re: 12 psi question... (just curious)

Actually, I think the injectors are all 280cc



Well, you're comparing apples and oranges. A lot of people make the mistake of comparing psi ratings of different turbos. The T25 on the MSP is much smaller than the T3 on the FM kits, for example. So at the same given psi...let's say X psi, you'll actually be moving different volumes of air between the different turbos due to the different sizes of the turbos.

For example the tires on my car are set to around 35psi of air. The tires on my bike are around 50psi or so. BUT, which tire is actaully holding more air? The car tire of course, just because of the difference in volume. So just know that comparing psi is only good when talking about the same turbo.

So just pulling numbers out of my @ss, I'd probably say that a T25@12psi is probably about the same amount of air (typically measured in CFM...Cubic Feet/Minute) as a T3 at around 9psi. Again, that's just a guess. But I'm just trying to illustrate my point.

But let's pretend I'm right, and 12psi on the T25 is about the same as 9psi on a T3. The guys who ran 9psi on the T3 ran into engine problems. Why? Fuel and ignition timing management.

So to answer your question, yes, i BELIEVE it can be done, IF managed properly.

i love it when it is sumed up so well.
good job dino!

 

[Little Beavis]

Wow! When your ass talks, people need to listen!

 

[Kooldino]

LOL, tell that to my roomate. My ass has been talking all night. Damn baked ziti...

:-D

 

[LinuxRacr]

Great! Let's keep putting out some good info here!(thumb)

 

[boostisgood]

http://64.225.76.178/main.htm

This is the link to Turbonetics compressor map site. Here, you can find the efficiency of most garrett turbos, along with a few others. This is a pivotal part of tubo charging a car. Finding an efficient power snail for what you want.

There is more to it then just these maps, but its basically the starting point for building a turboed car.

 

[I-Am-Chris]

Re: Re: 12 psi question... (just curious)

Actually, I think the injectors are all 280cc

man iwish someone would clear this up? is it 280 or 310. I need to know for emanage.

 

[perfworks]

Re: Re: Re: 12 psi question... (just curious)

man iwish someone would clear this up? is it 280 or 310. I need to know for emanage.

they are both the same 280cc at 40 psi

 

[dficken]

Thanks for clearing that up kooldino. After I posted that, I was reading a bit more I noticed there was a fairly big difference btwn the two turbos. (I also realized that the injector size may be the same... I think everyone is still waiting for an "official" confirmation from someone)

Oh well... still learning...

Anyhoo... So lets say you wanted to "safely" reach this 9psi mark in a turbo p5 or mp3. Would it be as easy as putting in a MSP ECU and then bump up the psi? (considering you don't reach the 225 HP mark which i believe the stock rods threshold)

 

[perfworks]

Thanks for clearing that up kooldino. After I posted that, I was reading a bit more I noticed there was a fairly big difference btwn the two turbos. (I also realized that the injector size may be the same... I think everyone is still waiting for an "official" confirmation from someone)

Oh well... still learning...

Anyhoo... So lets say you wanted to "safely" reach this 9psi mark in a turbo p5 or mp3. Would it be as easy as putting in a MSP ECU and then bump up the psi? (considering you don't reach the 225 HP mark which i believe the stock rods threshold)

mazdaspeed has alredy "officialy " cleared it up

280 cc at 40psi at idle.all of the protege fs

 

[spoolinmp3]

Chris just make sure that you monitor you injector duty cycles and that they do not surpass 85% After that you will be taxing the injectors and they will go static. Put some 530 in there

 

[BremertonMSP]

mazdaspeed has alredy "officialy " cleared it up

280 cc at 40psi at idle.all of the protege fs

So you are saying this is what they "officially cleared up? Look under the section, "Turbocharged Engine"

http://www.mazdausa.com/MusaWeb/displayPage.action?pageParameter=modelsPerformance&vehicleCode=PRZ

If so, where was it put out to the public?

 

[LinuxRacr]

Time for some part number backup here. BRB.

 

[Chojin]

Hey Everyone,

Here are the Fuel Injector part numbers for ALL 2.0L FS motors 2001-2003:

FSJ2-13-250 - Green
FSJ3-13-250 - Purple

The MazdaUSA website mistated the info. regarding the fuel injectors. Though the spark plug info. is correct on the website.

Later.

-Shawn

 

[Logan]

This doesn't make any sense.
PSI is PSI.
Pounds per square inch.
If one turbo has compressed the air to x psi, and another, larger turbo, has also compressed the air to x psi, why would they be different volumes of air? They are both compressed to the same PSI...

 

[Chojin]

Logan,

You must take into account cfm - cubic feet per minute. Big turbo A at x psi will have a higher cfm flow rate than Small turbo B at x psi.

-Shawn

 

[spoolinmp3]

The air is also cooler from a bigger turbo thus taxing the I/C system less and keeping charge temps cooler means more power