Me and my friend were talking and were debating that if a truck had a blower on it, would the addition of headers increase or decrease the boost. I thought that headers might slightly decrease(not a large amount at all) boost while still adding horse power.. He said that the boost would increase inside the engine because the exhaust was leaving faster...the only thing we agree on is that there is hp to be made with headers on a boosted app. Someone clear this up for us..thanks

 

I think the boost will decrease.

 

Intake
more flow in=boost up/less flow in= boost down

Exhaust
more flow out=boost down/less flow out=boost up

were talking small #'s here.

 

less boost but not much, with the additon of the headers and less boost it will make more power, I am aware you prolly knew that..

 

since you agree that with headers the exhaust gasses leave faster.. that to me would mean less resistance to the flow of air in the engine. This means less boost pressure and that decrease in pressure does't mean loss of hp.

 

i've been wondering myself about this, except i don't know if it might be different in the case of a turbo. I've been thinking about putting headers on my truck, but exhaust heat is good for turbos and the headers would dissipate heat faster.

 

Save your money for another project. I switched from LT headers to factory exhaust manifolds. Could not feel any increase or decrease in power.

 

Good to know, thanks

 

Boost is a measure of resistance. Less resistance=better flow=less boost=same power with less boost.

 

It all depends just how restrictive the exhaust system is. I had a friend who had a 9 PSI Vortech centrifugal on his Vortec 350 truck. He measured 10 psi of backpressure in the stock headpipes and cat. He went to Thorley headers and dual 2 1/2" cats and headpipes and his back pressure dropped to 4 psi.

We was at 10-11psi and then he dropped to 9psi after the header exhaust install. He said power was up dramatically after the swap.

Boost will go down if you remove restrictions. Same as if you added higher flow heads, the boost will decrease but power will go up.

peace
Hog