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I've read a comment on YouTube saying boost doesn't kill motors, power does.. What's that mean exactly.. Like another comment said you can run 25psi and only make 140whp but run 10psi and make more.. How is that even possible. I always thought the more the psi the more the hp
 

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95 civic coupe
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To much power in general? Sounds like whoever said that 25psi would make 140whp and 10psi would make more is a dumbass. I mean, did he based it on a lawnmower or something? :lol: No seriously... I guess in a way to much power could wear down a motor if it's pushed passed its given purpose, and this is why we tune our cars to monitor and make sure that the motor is performing like it should. It's all about making sure that all the components are working well with each before even proceeding into cranking the boost to 25psi or whatever nonsense the guy was saying on youtube. Any motor can make power if built right, proper parts, methods tuning etc... And yes more boost more power, literally speaking.

Built+Tuned+Boost=power


 

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91 Civic SI hb/ 01 GSR
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Its air volume that matters. Psi is the measure of resistence to the air being pushed into the motor. So it works out that a small turbo pushing 20 psi can make alot less power then a big turbo pushing 9psi.. if you have a 3" tube filled with 9 psi there is more air in that tube then a 1" tube with 15psi.

Try blowing through a straw, and also a toilet paper tube. The straw will have higher pressure but alot less air. The toilet paper tube will have next to no pressure but loads more aire flowjng throight it. Thus the lower pressure (psi) wil make more power.

Volume not pressure.
 

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Also say you have a stock motor and the rods will break at 200 hp. They dont care if you have a tiny turbo pushing 30 psi to make 200 hp or a huge turbo pushing 5 psi to make 200 hp. Either way it doesnt care about psi it cares about 200 hp because then when its going to break. Hx35 vs 13g. This is why people buy bigger turbos and not just run small ones at high boost levels. You heat shit up and added pressures.
 

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Add to what the others said, drop in a low lift, long duration cam with a bunch of over lap you blow most the air/fuel mix out the exhaust.

That will kill your HP quick.

The lbs/min rating on turbos range widely, so the lb/min from a T25 will be much than the lb/min of a HX40
 

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Also say you have a stock motor and the rods will break at 200 hp. They dont care if you have a tiny turbo pushing 30 psi to make 200 hp or a huge turbo pushing 5 psi to make 200 hp. Either way it doesnt care about psi it cares about 200 hp because then when its going to break. Hx35 vs 13g. This is why people buy bigger turbos and not just run small ones at high boost levels. You heat shit up and added pressures.
Stock internals break 200hp you say, but there's this guy here in California (long beach) by the name of Compton Rob, he has built a 500hp single can on stock internals.. I'm not bull shitty neither
 

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proof? stock rods at 500hp? d series rods? not integra?
 

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I just picked a number. I dont mean they will break at 200hp .it was to show how psi doesnt matyer
 

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I just picked a number. I dont mean they will break at 200hp .it was to show how psi doesnt matyer
So pretty much everything needs to be aftermarket and nothing stock with a turbo?
 

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Nope.

You can run upwards of 200hp or more, if the pressure in the engine doesn't reach critical levels, so the rods cannot push the car as fast as the air and gas and spark are coming in. You can guess what happens then.

Then there is revving beyond stock levels to reach the power in the FI application in the first place........but you did not ask about that.
 

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Nope.

You can run upwards of 200hp or more, if the pressure in the engine doesn't reach critical levels, so the rods cannot push the car as fast as the air and gas and spark are coming in. You can guess what happens then.

Then there is revving beyond stock levels to reach the power in the FI application in the first place........but you did not ask about that.
Up until recently, I knew nothing about any kind of turbo cept which cars are now stock with them and my friend had one catch on fire. (his own fault)
I got interested because I would like to build a car. I figured I would do more research on turbo. I know a lot of things about stock motors. But nothing about turbo or boost. So it is a learning process for me.
 

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There is some super good reading around here on proper building method theory and in between.

First bit of advice, knowledge, whatever...

Fast, cheap, reliable, you cannot have all three, your fun and longevity depend on route taken. Welcome, make an intro post, post pics, rejoice.

Whoshot out.
 

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Psi is irelavent (probably not spelled right)
Its all about cfm.
To put it simple, smaller turbos flows less cfm at a given psi the a bigger turbo at the same psi level.

Think 18wheeler tire @40psi vs a small doubt tire at 40psi. Not the same. Amount of air in them, but still 40 psi
 

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Psi is irelavent (probably not spelled right)
Its all about cfm.
To put it simple, smaller turbos flows less cfm at a given psi the a bigger turbo at the same psi level.

Think 18wheeler tire @40psi vs a small doubt tire at 40psi. Not the same. Amount of air in them, but still 40 psi
To the original poster, think of this this way blow really hard through a straw you can reach a certain PSI. Now even though the PRESSURE is really high, the actual VOLUME of air you are forcing through is small. Take a a large hose or pipe, and force the same PSI through; the CFM will be higher but the same pressure. which contains more air?

PSI is a measure of pressure, CFM is the actual volume of air being delivered. That is why it doesn't matter if you have a turbo that can deliver 100PSI of boost if the CFM is low, pressure doesn't matter, CFM does; the more volume, the more fuel in the motor, the more power.
 
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