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I don't know why y'all are scared about high mileage motors and a sudden case of boost, you already know some motors can run it no matter the mileage...don't be scared as much people we seen blow their motors on start up...
 

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I don't know why y'all are scared about high mileage motors and a sudden case of boost, you already know some motors can run it no matter the mileage...don't be scared as much people we seen blow their motors on start up...
I will forever be scared of blowing a QR. after blowing4-5 it sticks with you lol
 

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Mine had 127k miles on it. perfect compression. and it popped 3k miles after i boosted it lol 7 psi no timing added. Spun a bearing.
 

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I will forever be scared of blowing a QR. after blowing4-5 it sticks with you lol
I find this discussion interesting. I’ve always read that so long as you steer clear of 300HP, the QR should be able to handle boost. If turbocharging is too expensive along with a full NA build, what about supercharger or pro charger?
 

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I find this discussion interesting. I’ve always read that so long as you steer clear of 300HP, the QR should be able to handle boost. If turbocharging is too expensive along with a full NA build, what about supercharger or pro charger?
supercharging is 10x more expensive. You need a custom cnc bracket made to hold a supercharger, and if oyu can find a small one, you still have to make everything else to make it work. If you can find a used kit for a b15, your gunna pay an arm and a leg for it.

Horsepower does not kill engines, torque does. Horsepower is imaginary. It does not exist. We invented it. Torque is the physical force on an engine. So yea, if you run a super lazy turbo that is WAY too big, you can make 300+ horsepower, but thats because the torque curve will be line a NA curve which means less stress on the engine. But the car will not be as fast or efficient.

And also, the places that are saying the qr can handle near 300 whp are probably talking about one with less than 120k miles on it. Good compression, good bearing wear. that number really does not apply to a qr these days. They are all beat to shit lol
 

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supercharging is 10x more expensive. You need a custom cnc bracket made to hold a supercharger, and if oyu can find a small one, you still have to make everything else to make it work. If you can find a used kit for a b15, your gunna pay an arm and a leg for it.

Horsepower does not kill engines, torque does. Horsepower is imaginary. It does not exist. We invented it. Torque is the physical force on an engine. So yea, if you run a super lazy turbo that is WAY too big, you can make 300+ horsepower, but thats because the torque curve will be line a NA curve which means less stress on the engine. But the car will not be as fast or efficient.

And also, the places that are saying the qr can handle near 300 whp are probably talking about one with less than 120k miles on it. Good compression, good bearing wear. that number really does not apply to a qr these days. They are all beat to shit lol
I never even went by that number to be honest. My shit blew up in 2 days at 310whp at 45k miles on it. Point is the qr motor stock is a gamble once boosted. Just like FRe said trq is the killer. Dynos base their horsepower numbers of what torque it makes. Horsepower is just a tool
 

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I never even went by that number to be honest. My shit blew up in 2 days at 310whp at 45k miles on it. Point is the qr motor stock is a gamble once boosted. Just like FRe said trq is the killer. Dynos base their horsepower numbers of what torque it makes. Horsepower is just a tool
Well that’s depressing. So a car like mine pushing 181K miles on the odometer would not be able to handle a power increase to 250 HP without upgrading internal parts? If that’s the case, I’d rather probably stick with simple NA bolt ons or just get a different daily platform like a Focus ST (which I’ve been really down bad for, for the past few weeks even though my Sentra still runs well and I know for a fact I can’t afford one rn)
 

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Well that’s depressing. So a car like mine pushing 181K miles on the odometer would not be able to handle a power increase to 250 HP without upgrading internal parts? If that’s the case, I’d rather probably stick with simple NA bolt ons or just get a different daily platform like a Focus ST (which I’ve been really down bad for, for the past few weeks even though my Sentra still runs well and I know for a fact I can’t afford one rn)
I owned a focus st for about a year. SLOW AF on the top end. My AWD CVT Juke with a vf48 and a stock tune WALKED it lol Upgrade the turbo and get a good tune and they are little rockets.
 

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I owned a focus st for about a year. SLOW AF on the top end. My AWD CVT Juke with a vf48 and a stock tune WALKED it lol Upgrade the turbo and get a good tune and they are little rockets.
I know there’s inherent risk in any car modification but would upgrading to a bigger turbo cause any reliability issues? I don’t doubt there’s probably a Cobb tune out there that could be recommended but still. Also isn’t that technically a problem with the B15 Spec-Vs too? That was mainly my interest in boosting mine and since it’s an 02, I know I’d have to get a standalone ECU to tune it. What is a VF48 btw?
 

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Rebuild the interals on the spec. I'ts not that difficult, and pretty cheap in terms of buying awhole new to you car.
 

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I know there’s inherent risk in any car modification but would upgrading to a bigger turbo cause any reliability issues? I don’t doubt there’s probably a Cobb tune out there that could be recommended but still. Also isn’t that technically a problem with the B15 Spec-Vs too? That was mainly my interest in boosting mine and since it’s an 02, I know I’d have to get a standalone ECU to tune it. What is a VF48 btw?
Bigger turbo is only more stress on the engine if you run more power. Example; it takes 18psi on the focus st to make its stock power. The torque curve is terrible, very clearly outflowing the turbo from the factory. This makes the car slow over 3500 rpm. If you upgrade to a gt28 they make a kit for, you can then run 14psi and make the same peak hp number, but with a significantly BETTER torque curve. This means the car is faster, on less boost and less stress.

Turbocharging a NA car is a totally different ballgame. Your adding significant amount of air that the engine was not designed for.

vf48 is a STI turbo, I use them on MR16DDT's for a small upgrade over stock.
 
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