How much boost can these engines take?

[AFaceInTheCrowd]

hmm... so 10 psi on stock internals and stock intercooler huh. sounds pretty good on an MSP. that would bring whp to bout what... 180? 200?

 

[AGR]

There is not much reason to go over 10 psi with the t25 since it is very inefficient in its application.

Inefficient? Interesting. To me; the T25 is quite efficient; when you consider it is bolted to a stock 2.0 Protege motor. It seems to many of the owners here - it simply isn't enough 'car'. The way I look at it; considering the competition: Honda Civic Si (one that isn't mentioned too often here), the Focus SVT, Nissan SE-R Spec-V....... I think Mazda did a pretty damn good job with the MAZDASPEED.

But hey!! I'm just a simple man, that likes his car for what it is; with just a few 'small' additions.

 

[1sty]

He's talking about turbo efficiency not fuel efficiency.
the T25 will just start throwing air to hot to utalize after 10 PSI.

 

[AGR]

He's talking about turbo efficiency not fuel efficiency.
the T25 will just start throwing air to hot to utalize after 10 PSI.

Ok. I was referring to the overall efficiency of the turbo; as it is standard w/no mods.

 

[turboge]

It'll flow efficiently past 10psi.. I don't know where you guys are coming up with this magical number.

 

[changedman]

keep providing kick ass information like you all have been! (thumb)

 

[yashooa]

Cool

There is not much reason to go over 10 psi with the t25 since it is very inefficient in its application. As far as getting rid of boost cut its very simple get a boost cut defender HKS sells them and they should work. I have been running 210-230 whp at 10 psi for some time with no problems. But thats at the ragged edge. I would not reccomend going higher especially with the stock turbo.

Eureka! So 200-215 WHP is do-able without touching the long block!
So get a kit together, intercooler, boost controller, etc etc etc.
Well if in fact we are talking about a MSP with a stock long block.

 

[LinuxRacr]

What's up with the tripple posts?:wtf:

 

[yashooa]

What's up with the tripple posts?:wtf:

Damn dual T1 is freaking out today. I only hit submit once but the damn thing went crazy. I didnt see it until now.

DOH!(hand)

 

[LADY MSPD]

whats the compression on our mazdaspeed engines, it is lower than the all motor engine right???

 

[turboge]

9.1:1, no different.

 

[spoolinmp3]

It'll flow efficiently past 10psi.. I don't know where you guys are coming up with this magical number.

Its not a magical number....the t25 can easily boost 18psi however its what application we are reffereing to. Look at a dynoplot with a t25 on a 2.0 liter engine and you will see it starts running out of steam after 5 grand.

Inefficient? Interesting. To me; the T25 is quite efficient; when you consider it is bolted to a stock 2.0 Protege motor. It seems to many of the owners here - it simply isn't enough 'car'. The way I look at it; considering the competition: Honda Civic Si (one that isn't mentioned too often here), the Focus SVT, Nissan SE-R Spec-V

I am not denying that mazda did a damn fine job on the car...it is better IMO than all the other cars you stated. However the general consensus is that unfortunatly Mazda skimped on 2 main areas....The intercooler and turbo. This is very common on an oem application.
The t25 has been used on 2.0 liter turbo eclipses and gained the name t"2 small".
Its a great turbo just not for our application. Most oem cars have little turbo's because it gives the averegae driver a false sense of power. Due to super quick spool up torque comes on strong in the lower RPM's but a little turbo creats unbelievable amounts of heat and back pressure becoming ineficient in the mid to upper power curve.

Thats why I state that there is really no point going over 10psi on this turbo.
More psi does not always mean more power. Its verry common in oem applications with undersized turbos to see cars making the same amount of power at much lower boost levels.
Forexample the wrx will make the same amount of power at 16psi if not more vs 22psi.
So not all boost is created equal and more boost does not always mean more power.....Thats aside the MSP rocks
(rockon)

I wish I could have one

 

[LADY MSPD]

how come they didnt make the turbo models a lower compression??? thats stupid, that explains why we cant boost over 10psi, my boyfriend has a 88mazda mx6 turbo with all stock internals is boosting 18psi and hes running 13's why couldnt our motor be able to do that ...****** mazda!!!

 

[turboge]

Look at a dynoplot with a t25 on a 2.0 liter engine and you will see it starts running out of steam after 5 grand.

Hey lets do that! Take a look.

Now, what you see is steam running out at 5000rpm? No, not really, this is called poor tuning. The turbo is still making very good power past 5000rpm. The fact that the A/F is near 10:1 is why the torque curve is not as flat in those last 1500rpm.

If you want to see a turbo that "runs out of steam" look at my dyno chart of my 1.8 Turbo protege.

That is a turbo that runs out of steam. The T25 retains juice till redline. Given a few more lbs of boost and the ability to tune the A/F I think it's a very capable turbo.

Its a great turbo just not for our application.

Who's application? I think it works perfectly for it's design. A street car that can handle like a champ and pull out of the turns at full throttle without lighting up a storm of inside tire.

Unless you mean drag racing? I surely don't think anyone bought an MSP for that.

 

[AGR]

how come they didnt make the turbo models a lower compression??? thats stupid, that explains why we cant boost over 10psi, my boyfriend has a 88mazda mx6 turbo with all stock internals is boosting 18psi and hes running 13's why couldnt our motor be able to do that ...****** mazda!!!


Uh oh! ...another potty mouth girl. Do you eat with that mouth? Do you kiss your Mama with that mouth? (chair)
(rofl) (pukey) (pukey)

 

[LADY MSPD]

sorry about my french...

 

[AGR]

sorry about my french...

I was just messin' with you!

 

[JasonH]

how come they didnt make the turbo models a lower compression??? thats stupid, that explains why we cant boost over 10psi, my boyfriend has a 88mazda mx6 turbo with all stock internals is boosting 18psi and hes running 13's why couldnt our motor be able to do that ...****** mazda!!!


Uh oh! ...another potty mouth girl. Do you eat with that mouth? Do you kiss your Mama with that mouth? (chair)
(rofl) (pukey) (pukey)

You didn't use "quote" there and for a second I thought you were talking about your boyfriend (flash)

 

[turboge]

how come they didnt make the turbo models a lower compression??? thats stupid, that explains why we cant boost over 10psi, my boyfriend has a 88mazda mx6 turbo with all stock internals is boosting 18psi and hes running 13's why couldnt our motor be able to do that ...****** mazda!!!

Would you rather pay another $3-4000 for your MSP at the dealer? Maybe more? Back in the 80's rallying was a way to show off what the manufacturers could produce. So instead of making new parts they just manufactured a ton of them and put them in production vehicles. I haven't seen too many proteges or 323's in the rally scene past 1994.

The 90-94 Proteges came with your choice of 8.2:1, and 8.8:1 compression. 9.1:1 is not a high ratio, and it's not the reason you can't boost over 10psi. The reason is your ECU, it is poorly tuned by mazda in an attempt to make an awesome idea come to life. Replace that and you can run alongside your boyfriend at the 1/4 mile.

Also, that little 2.2 turbo motor running 18psi, that's hot air. The little VJ12 or 14 that is on that motor is almost as small as the VJ20 I posted up on the dyno sheet above.

 

[yashooa]

Also, that little 2.2 turbo motor running 18psi, that's hot air. The little VJ12 or 14 that is on that motor is almost as small as the VJ20 I posted up on the dyno sheet above.

"Hot air" heehee