Equal length headers >> best associated backbox?
 

Gents,

I am facing a dillema - just bought a classic WRX with equal length headers (STi7 JDM engine, TD05-16G, FMIC, ACVR & PFC - running circa 350/350)

Although the exhaust noise is pretty sweet and it sounds like a superbike I am missing the burble. I have heard a mates car running an HKS Titanium BB and it generate an immense sound........Currently my BB is a custom one with a fai amount of baffle to dull down the full decat resonation....

My question is this :- in your opinion, what is the best backbox to mate the Eq. Leng. headers to from an exhaust note perspective.:norty:

I tempted to switch the Gruppe S headers with ported OEM ones but fear this may be at the expense of torque/power.

Thanks folks

Cal

p.s this is the sound I really crave once again :- http://www.youtube.com/watch?v=JuCZMvMnyPw but I do dig the headers performance

I don't really get the post it seem's you've answered your question.

You've just got to make the decision scooby burble or the small performance advantage that the equal length give you.

My question is basically - what is the best back box for getting the best exhaust note from equal lenghth headers i,e what yields the best rally slag sound at a decent cost ;)

Cal - ARE you 100% sure your Gruppe-s ones are equal length?

Equal length headers were never on the WRC cars of the era you speak of...................... you can't properly replicate a sound that is made by the offset design of the headers if the offset design is removed IYSWIM.

Equal length and off-beat Scooby rumble - never the twain shall meet :(

Russell

ps - my system sounded like it did because it was mated to GT Spec II headers.........SEMI-EQUAL LENGTH (1/2 way between your equal length Gruppe-s ones and OE Ported ones).

Cal -

I have the old system currently on the TypeR which you can have if you like?

Go and see Angela and get the keys off her, start up the car and see what you think.....................

If you can wait until I get back, we'll fit it to your car and you can run it for a few days and see what you think? It's S/S but sounds as deep as the HKS did :D

Russell

FINALLY - A couple of extra things to remember.

1 - PORTED OE headers will give FASTER AND EARLIER SPOOLUP than your Gruppe-s ones (+/- 600rpm sooner, Gruppe-s ones move your torque curve further up the rev range)

2 - PORTED OE headers will give a little more torque than Gruppe-s BUT Gruppe-s will give loads more Top-end!

So it all depends on driving style............keep it on the boil all the time (over 3800rpm) then the Gruppe-s are best being kept on the car. BUT if you want very similar kick (torque) in a similar curve but lower down the rev range, fit the PORTED OE headers.

Ask Harvey about the PORTED headers and ask Mark @ Lateral or AndyF about the Gruppe-s ones and form your decision from there. These guys know their stuff so use and abuse their knowledge.

Russell

You might want to check your facts in the last post Russell ;)

keep yor current headers so I can buy WUZ's ported OE headers lol!!!

seriously though if u miss the burble get a set of OE headers back on and take the power loss just for that noise

Here is mine....sorry only a short clip but I like the sound....running a Ganador titanium.

http://www.youtube.com/watch?v=VQskYOKXbJs

WUZ - cheers for the note. There is not a sniff of a burble so I am 100% sure they are fully equal. What do you reckon Andy would charge for a quick jig of the map ? £200 or so ? I shall have a think about it and let you know. I am missing the burble BIG league ! :wonder:

According to information from Gruppe-S suppliers in the US (too late to speak to UK suppliers), the OE PORTED ones will spool sooner and give more torque lower down as the Gruppe-S ones more everything higher up..... so OE ones give more torque in the lower rev range than the Gruppe-S ones.

That's what I was trying to say. Sorry if it got misconstrued.

Higher up the rev range, the Tubular headers do a bit better then OE PORTED.

I am hoping Harvey will pop into the post and give his views on these opinions as he is more of an expert in the characteristics and flow dynamics of Tubular headers versus PORTED OE headers.