Which part of headers causes rumble?

[insanity007]

I've put some headers that I bought from Redline onto my 1996 v2 GF8 WRX and despite what the bloody bastards said, I've lost the rumble

What I want to know is, which part of the headers causes the rumble? Is it the flexy bend in the up pipe or the bent pipes bolted onto the engine?

I'm trying to find a way to keep the quicker spool while getting the rumble back.

Here's a pic of my engine after the heads were done before it was put back in:

[ADIKT]

Simple. Stick with stock headers. The unequal length of the headers before the collector causes the rumble. The more equal length they are less rumble. Yours looks pretty equal to me

Edit. I had semi tuned headers on my Rex. Still had a good rumble but it sounded unique

[petrolheadjman]

it's the lengths of the pipes coming out of the block, the uneven length in the factory ones give the rumble. since these are "equal length" supposedly it will sound like any other 4 cylinder turbo.

[insanity007]

Ok great.

That's what I thought. If I can combine the new bigger up pipe with the stock headers then I should be able to get quicker spool shouldn't I?

[insanity007]

 hate-evoz said:

but then you will only have a a/m up pipe and the rest of the system will be stock. It wouldnt matter with spool anyway . wat counts is the exhaust size from turbo back. imo

which is 3" all the way 8)

I thought better headers caused turbos to spool sooner?

[Guest]

 insanity007 said:

Ok great.

That's what I thought. If I can combine the new bigger up pipe with the stock headers then I should be able to get quicker spool shouldn't I?

Incorrect. The bigger the pipe the longer the spool time.Removing the restrictions and keeping the factory size is the best for spool.

Good power can be made on stock headers not sure whether tuned make a lot of difference or not hopefully scottspeed pops in on this thread he knows these things.

[D-Style]

*NB Its been well noted that the factory headers can handle up to around 400hp before they become a restriction.

[insanity007]

All I'm worried about is spool time. I'm fitting a TD05H and I know they can be laggy if measures aren't taken to counteract this.

[off2harrys]

the bigger up pipe will make it worse for spool as evowrx said.everyone seems to have different experiences with headers,my a/m unequal length made it worse for spool,i think the general consensus is usually equal=better performance,unequal=sounds pretty and you generally get what you pay for (as with everything i suppose).factory is best if youre only after spool

[ADIKT]

 insanity007 said:

All I'm worried about is spool time. I'm fitting a TD05H and I know they can be laggy if measures aren't taken to counteract this.

you would probably get the best spool from factory headers... just get them high flowed.

http://www.clubsub.org.nz/forum/index.php/topic,27825.0.html

[Fastfour]

Ive got some single scroll factory headers sitting in my shed if you wanted them, cheap cheap make an offer

[insanity007]

 Fastfour said:

Ive got some single scroll factory headers sitting in my shed if you wanted them, cheap cheap make an offer

I have factory headers and put them back on... still working out some issues with the new turbo but getting there!!

Have you done anything to yours?

[Bazza-NZ]

FYI - I have a set of those extractors and you should have a slight rumble at idle and under 1500RPM.

Also mine are for sale for anyone looking at purchasing a set.