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Maxpeedingrods gt2870 max psi?

781 Views 12 Replies 6 Participants Last post by  Georgia Eg
Hi guys
Im wondering what these mxr t25 can take.
Ive seen on their website that their recommendation is around 18psi, but i guess thats a safe limit(?).
Have anybody taken this turbo further?
Did it last?
I would be running 21-23psi (1.5-1.6bar) on a built d15 vitara bottom end with a z6 head.
Thanks in advance
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You could have probably put this in your other thread...
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PSI != power.


Your rods support a power level, not a boost level. Always tune for power, not PSI.

Turbo A on 15psi might make 200whp, whereas Turbo B on 15psi might make 300whp.


PSI != power.
You are right!
But ive seen dynos on similar builds when simply upping the boost and gaining nice amount of power. And im worried about that turbo: T25 T28 GT25 GT28 GT2871 GT2871R GT2860 SR20 CA18DET Turbo Turbocharger
I read that listing a few times and they list multiple turbos in the listing, so I'm not even sure which one you would be buying. However, there are things you need to learn about turbos. First is the efficiency range. Once out of that range, you are basically pushing hot air because the turbo is no longer efficient and the gains in power are negligible. If you are truly running a T25, then it maxes out in PSI at about 14 psi. After that, you would actually be doing damage to the turbo. A GT2860RS maxes out at about 18 psi. A GT2871r maxes out at about 22psi. And all of them are rated for different horsepower levels. The GT2860RS is the best compromise of the group, unless you're not building the engine.
Thats one exact turbo, its sizes are like the genuine 2871rs. Im not worried about efficiency, i saw that it can still deliver power upwards, but reliability. I know its gambling eith these china turbos, but its functioning perfectly on 17psi right now
"Im not worried about efficiency"


Then you probably shouldn't be using a turbo.
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Sorry, i didnt mean that. I shouldve said that i wont be out of the efficiency range by raising the boost 5-6psi
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I read that listing a few times and they list multiple turbos in the listing, so I'm not even sure which one you would be buying. However, there are things you need to learn about turbos. First is the efficiency range. Once out of that range, you are basically pushing hot air because the turbo is no longer efficient and the gains in power are negligible. If you are truly running a T25, then it maxes out in PSI at about 14 psi. After that, you would actually be doing damage to the turbo. A GT2860RS maxes out at about 18 psi. A GT2871r maxes out at about 22psi. And all of them are rated for different horsepower levels. The GT2860RS is the best compromise of the group, unless you're not building the engine.
I always wondered why some street/strip cars are pushing 30-40psi. Is that because of some stupid AR ratio or just sheer flow rate of the turbo i.e. gt42 on a b series
High boost + street driving = constant repair (usually)
I always wondered why some street/strip cars are pushing 30-40psi. Is that because of some stupid AR ratio or just sheer flow rate of the turbo i.e. gt42 on a b series
So basically they have too much turbo for the street and anything below that and it starts eating itself. Or they are numbers guys shooting for that specific magic number they think that they have to make. But with a 42 frame anything below 20-25 and you're close to the bottom of the efficiency range. Reasons they don't work as well and cars like mine with way less turbo frame are quicker stop light to stop light
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Hi guys
Im wondering what these mxr t25 can take.
Ive seen on their website that their recommendation is around 18psi, but i guess thats a safe limit(?).
Have anybody taken this turbo further?
Did it last?
I would be running 21-23psi (1.5-1.6bar) on a built d15 vitara bottom end with a z6 head.
Thanks in advance
WHATS UP,DADDYDAVE LIKE TO KNOW IF AND WHEN YOU BUY A SET OF MAX SPEEDING RODS I UNDERSTAND THAT YOU MUST NOTCH THE BLOCK PLUS THE TRAY UNDER THE CRANK FOR CLEARANCE ,
That's a lot of caps... This thread is about a turbo... Not rods..
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