How much hp should I expect from headers?

[mr_wizard]

I was told about 15-20hp, is this right? I have a 91' 240sx with a ka 24de and straight through exhaust. Other small mods.

EDIT: Also, while I'm on the subject, what headers would everyone recommend for the ka24de?
Modified by mr_wizard at 9:35 PM 1/24/2006

[naed240sx]

from a header, you are never going to make even 15 horsepower. Less than 10 for sure. I would say about 10 horspower with the exhaust and header(if both are well designed. Gains will be larger if your car is more heavily modified.

[mr_wizard]

This is going to sound ignorant and dumb, but how much do you think that would affect the quarter mile time?

[InsanityInc]

There really aren't any headers that are that good currently out there. Best I've seen is ~5 whp. A 3" exhaust is a much better investment. Way easier to install, too.

[mr_wizard]

There really aren't any headers that are that good currently out there. Best I've seen is ~5 whp. A 3" exhaust is a much better investment. Way easier to install, too.

Yep, got it already. Custom straight through 3"

I'm going for headers and intake now(cheap way), hoping to gain a total of 20hp from them both.

[ddgsxr504]

Yep, got it already. Custom straight through 3"

I'm going for headers and intake now(cheap way), hoping to gain a total of 20hp from them both.

Good luck with that!

[lrb_2000]

"MAYBE" 20CHP, but doubt it... no way you'll get an extra 20WHP...

[Fenvy]

how many hp? you will get 5 at best but with nothing else hcnaged, maybe 1 or 2, or at worst loose 1 or 2

[Ni2s4s0aSnX]

you might get 10chp, if your lucky, but nothing more than that.

[240Knightrider]

There really aren't any headers that are that good currently out there. Best I've seen is ~5 whp. A 3" exhaust is a much better investment. Way easier to install, too.

Have you heard of HOTSHOT? They are that good.

[mr_wizard]

Yeah, key word "hoping". I probably wont even gain 15 total from it all. But I think my straight through exhaust should help in gaining a little more than normal. Not sure why people make big deals out of headers and then charge an *** load for them (200 for hotshot) and then they make less than 5whp.

[240Knightrider]

If you want the best get Hotshot...some swear by them...

[InsanityInc]

Personally I wouldn't recommend the HS header. I have one and it's pretty poor in quality. Both the exhaust port flange and the cat flange are warped, so it doesn't fit right. Additionally, the HS header still only gives ~5 whp : http://www.ka24development.com...t.jpg

[240Knightrider]

Maybe you got a defect or something...You are the first Ive ever talked to that didnt like the HS header. Everyone else had awesome fitment and excellent response from it.

[SimpleEnigma]

I would prolly expect in the range of about 5-10 with combined header and exhaust which might be good for like a tenth off your 1/4 time

But seriously though....all the questions i have seen you post have been answered a million times before....search dude, the answers are here on this forum, i promise.

[mr_wizard]

I'm sure the answers are out there but they've got to be under some other subject, I've tried all sorts of variations. Thanks for your input though guys.

[TrueSlide]

Has anyone tried the S&S header?

[VinceSez]

i have the hotshot header, and i definitely like it! it feels like i gained some up top, but lost some power down low.

[240conv]

I dont know what header you guys are running but i got an OBX header and I dynoed and gained 12HP to the crank and 8rwhp.

[NateDogg]

1/4 mi improvement is not just from the hp increase, but also from the significant weight savings, approximately 40lbs. I would say at least .2 sec in the 1/4 will be gained.

S&S is currently the best designed header for the KA. Longer primary runners give a larger torque curve and the 4-1 design allows the engine to breathe higher up top. However, it has clearance issues, can't remember if its with the steering or ground clearance, or maybe both.

[naed240sx]

So you are saying the stock mani weighs more than 50 pounds? I find that hard to believe.

[InsanityInc]

The stock manifold is pretty heavy, but my HS header isn't a lightweight either.