Boost pressure loss?

SANTEEN

SANTEEN

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Just installed the Bassani's and it seems like a may have lost a couple psi. Seems like it maxes out at 5 psi. Do headers effect pressure loss, in the same manner that porting heads do? If not, then I may be losing pressure through one of the couplers.
 
They should not affect the boost pressure at all. Check all of your lines.
 
LitemUp said:
They should not affect the boost pressure at all. Check all of your lines.
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That's what I figured. I'll double check the couplers tomorrow
 
Well, did a little searching and apparently u can have boost loss from installing headers. It's even on Kenne Bells website. Supposedly, there is no power loss, just doesn't register, due to the loss of back pressure.
 
In my opinion! If your guage is ready less psi then you are making less hp!
 
I have always been told that whenever you make your engine more free flowing (better exhaust, porting, etc) you will loose boost pressure but make more horsepower.
 
Mighty1 said:
I have always been told that whenever you make your engine more free flowing (better exhaust, porting, etc) you will loose boost pressure but make more horsepower.
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That's basically what I'm reading
 
Mighty1 said:
I have always been told that whenever you make your engine more free flowing (better exhaust, porting, etc) you will loose boost pressure but make more horsepower.
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Don't have experience with forced induction on an SRT-10, but have run centrifugals and positive displacement blowers on numerous vehicles for almost 2 decades.

Yes... opening up the exhaust can (and normally does) result in a loss of boost pressure that you read at the manifold. However, you will not lose power (will typically gain some)... you're still moving the same amount (if not more) air through the engine.

Well-thought-out exhaust mods are excellent upgrades in a supercharged app like yours. Assuming you have the fuel system (which I think you do) and the rest of the parts to handle it, you should swap blower pulleys to regain the lost boost...and you will have significantly increased power, without significantly more cylinder pressure. It's a win-win.
 
Mighty1 said:
I have always been told that whenever you make your engine more free flowing (better exhaust, porting, etc) you will loose boost pressure but make more horsepower.
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With Stryker heads, the Hogans intake and long tube headers, the Paxton barely managed 4psi at 4000 RPM on my truck.
 
So we know that any improvement in airflow through the engine will probably lower boost pressure, what effect will having a cam "designed" specifically for a supercharger have on boost pressure?
 
Ram From Hell said:
With Stryker heads, the Hogans intake and long tube headers, the Paxton barely managed 4psi at 4000 RPM on my truck.
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Where you able to change pulley size and get the pressure back up? When my truck is running again it will have ported heads and intake, blower cam and no cats but will have a bottom pulley size of 7.5 inches which is 1.5 inches bigger than stock. I just wonder where my max boost will end up because I know we can't really go smaller on the blower pulley right?
 
Mighty1 said:
I have always been told that whenever you make your engine more free flowing (better exhaust, porting, etc) you will loose boost pressure but make more horsepower.
Click to expand...

Your exactly right!! Look at Eric's truck-Ram From Hell, there is a prime example, I'm just going to make an example here, if you have a blower putting out 10psi boost on an engine with stock heads and stock manifolds it will put out 10 psi boost due to resistance of pushing the air in a
pushing the air out which creates heat and limits the HP, but you take that exact blower and put it on Eric's set-up it will only hit 6 psi and make the same or maybe a little bit more HP but it won't be less,then you spin that blower higher on Eric's engine so it makes 10 psi and the HP will be aprox 40% more gain again.
Boost pressure is only a # that shows how much pressure is being forced into the engine and if you get your engine to flow better and more smoothly your boost will drop but your HP won't and usually increases!
Another example is Prof's truck, boost is lower but more power because his engine breaths properly.
 
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Yes, a cam with valve events specific to FI will keep the boost # in place for the most part as part of your boost won't be blown out the exhaust ;)
Headers have the same effect NA or FI, you'll still loose a bit of bottom end torque! Any change to the breathing of the engine will affect boost pressure. Put a larger intercooler on it and see the numbers drop more! Your
Making more HP with a very small loss of torque from idle to about 2000rpm.
 
very very true....this is an issue with the older cobra's and their eatons, you don't want to add headers unless your pushing enough air to benifit from them.....how to figure that out before you swap....I don't know!
 
Boost problem solved. The outlet pipe from the cooler, came loose. All good now. Well kind if. Got a new problem. Gotta get with stinker on it.
 
Mighty1 said:
Oh no, what happened??
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Trans is done. No reverse and won't roll in neutral. It actually is in drive, when it's nuetral
 
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