HP difference from upping the boost?

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'08 CPW Mazdaspeed 3
Kind of stuck wondering if a boost controller is worth it at this point. I've read that you can get up to about 18psi before the boost cut comes in....stock boost goes up to 15psi as far as I can tell. So how much HP are we talking about with that extra 3 psi? Anyone have any real data on that?
 
I personally wouldn't add a boost controller without analyzing things with a data logger in stock form. Get a boost gauge too....that's step one. I have no idea how the MS3's maps can be scaled.

I've not had a chance to review my car as she is, but the dyno charts I looked at for stock ones showed a couple of nasty dips. That tells me that the ecu is already compensating. If the car is already compensating for more boost and it gets cold and you have even more boost your running out of range for sure.

Kind of stuck wondering if a boost controller is worth it at this point. I've read that you can get up to about 18psi before the boost cut comes in....stock boost goes up to 15psi as far as I can tell. So how much HP are we talking about with that extra 3 psi? Anyone have any real data on that?
 
the general rule of thumb is about 5-7hp for every psi of boost.

On this application I'm guessing. I've seen people put 6psi into rsx type-s motors and extract anywhere from 50-100 wheel horsepower......

I was wondering the same thing, think a mbc is my next step, but really its to prevent boost cut without removing the security all together with a clamp
 
On this application I'm guessing. I've seen people put 6psi into rsx type-s motors and extract anywhere from 50-100 wheel horsepower......

Im sure they had other mods done besides being stock, which is what he is asking about.

the more mods you have of course the more hp per psi you are going to gain.
 
type-s also has high compression, so every pound is going to go further as well. but sorry, getting off topic. is 1psi worth so little on this car? If so, why are people pushing past 18psi at the risk of blowing their turbo for a few horses?
 
type-s also has high compression, so every pound is going to go further as well. but sorry, getting off topic. is 1psi worth so little on this car? If so, why are people pushing past 18psi at the risk of blowing their turbo for a few horses?

Im not 100% sure on the hp increase, Im just going by what i've seen and read in all my turbo learnings.

People are risking their engines because they want as much power as possible for as cheap as possible and a MBC is rather cheap. And because they think mazda will warranty it if it blows.
 
Im not 100% sure on the hp increase, Im just going by what i've seen and read in all my turbo learnings.

People are risking their engines because they want as much power as possible for as cheap as possible and a MBC is rather cheap. And because they think mazda will warranty it if it blows.

Ive been running 18 to 19 psi with 0 issues for more than a year. There is no one that screwed up their engines from this. Search and find.
BTW if some one wants A MBC and a BCD i have it for sale.
 
type-s also has high compression, so every pound is going to go further as well. but sorry, getting off topic. is 1psi worth so little on this car? If so, why are people pushing past 18psi at the risk of blowing their turbo for a few horses?

18 psi is good for about 20psi. check the dynos. The turbo is good for 20s somewhere, there is a thread on it.
 
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type-s also has high compression, so every pound is going to go further as well. but sorry, getting off topic. is 1psi worth so little on this car? If so, why are people pushing past 18psi at the risk of blowing their turbo for a few horses?

not necessarily a few horses when you look at it like this...

5-7 hp per psi...
15 hp conservatively for 3 psi. this puts us at 18.6

15 hp for about 50-75 bucks is better than a race pipe.
you'll get boost cut, so get a boost cut defender or map clamp as well...but even with that cost taken into consideration, you're looking at around 150-175 tops again for 15 hp.

does running an extra 3 psi in our cars hurt it?
from what i understand, no
 
I thought I was hearing somewhere 20-22psi is the max this turbo can spin, causes excess heat and warps the compressors. Might have been 22-24psi???

Anyway, as soon as my paycheck comes in next week I'm jumping on a mbc and clamp. I'll let you guys know how it goes. Think I'm going to follow the trend and run 17.9
 
Anyway, as soon as my paycheck comes in next week I'm jumping on a mbc and clamp. I'll let you guys know how it goes. Think I'm going to follow the trend and run 17.9

If you run 17.9psi you wont need a map clamp!, you only need the map clamp if you plan on going past 18psi, the map clamp is used to lie to the ecu that you dont exceed a certain psi so it doesnt cut the boost
 
If you run 17.9psi you wont need a map clamp!, you only need the map clamp if you plan on going past 18psi, the map clamp is used to lie to the ecu that you dont exceed a certain psi so it doesnt cut the boost

I thought someone asked that and got the answer than you needed them both together..... I've had a long week at work. I teach in a title 1 school and I am getting ready to leave! :: phew :: Friday at last!!

I think I will get a boost controller, THEN if I still get cut or have issues, I will put on a map clamp
 
I think I will get a boost controller, THEN if I still get cut or have issues, I will put on a map clamp
I picked up both....but like you I'm just going to install the MBC and run it at 17.9.
If I get boost cut then I'll install the BCD.

Question:
Will it spike with the MBC? If so, approximately how much?
 
idk, i get a spike, but some people don't. i think it depends on a number of things...firstly and foremost, are you just slamming on the gas pedal? if you are doing that, you will definitely spike.
 
does anybody knows how to dial down the boost from a defi boost controller? I am boosting around 21 too rich for me.
 
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