Unequal 4 Branch = Loss Of Flat 4 Burble?

[scottishtaffy]

after putting a new 4 branch stainless manifold on last year ive lost the classic burble. i have a straight cut 3in stainless one pice exhust and change it fo. r a two piece with the front bullit in line silencer on but tho it made it quieter i seem to have lost a bit of power like its strangling it a bit but still no burble. has anyone come across this when fitting 4 branch manifolds? below is a pic of the manifold .

i miss the burble but am also wondering if when i get it mapped it might make a difference as the ecu will be matched to the flow. it was a standard manifold on before.

[mctwistuk]

I know that headers like tg spec 2 etc reduce the burble due to be more equal in length. What type headers is it you bought?

[boab type ra]

I have japspeed headers on my ra and still has the burble but sounds way different when on high revs. I did not lose power but the turbo spools up way quicker the fuel cut defender kept cutting in

[lewisscoob]

Mapping with your headers won't change the tone.

Personally Alun, I would be getting a set of standard headers sent to Alyn at AS Performance, get them ported and get a trick up pipe while your at it. You'll get the burble back and gain a few hundred rpm in spool which will make a noticeable difference come mapping time.

[scottishtaffy]

not sure what type/make. but hey are un equal length so not sure why it lost the burble chris. ive not lost power having the 4 branch , only when i put the 2 piece 2 silencer system i lost a bit of top end power. yet the striaght thru 1 silence is fine. and wha kind of price would that set me back lewis as like the sound of that with the standard manifold lewis. also is there much benifit between the stainless 4 branch and the standard?

[lewisscoob]

You'd really need to speak to Alyn about prices but probably between £200 and £250 for ported and heat wrapped headers plus another £140 I think for the trick up pipe. Don't quote me on that thiough. Alyn is a good honest trader, will always strive for the best price and his service is second to none.

If you were worried about cost for the headers and up pipe I'd suggest just the up pipe as that's where the gains are made really, the porting is mostly removing the cast imperfections.

Where headers and up pipes are concerned its a common misconception that bigger is better - wrong. With increased bore, you reduce the velocity of exhaust gas - that's not good. Using the standard bore headers and smoothing out the imperfections in the casts, and fitting an up pipe with its outlet matched to the size of your turbo inlet, gas flow is smoother, less turbulent and of a higher velocity which inturn spools up the turbo quicker.

The only advantage I see on tubular headers over standard cast ones is of weight saving or if you were going for 400hp+.

[Bryan d]

A I c you got the equil length that's y you not got the burbill loon I have her of this to we them you need the unequal 1

[lewisscoob]

Fck me Bryan, was that English or an arrangement of words?

[mctwistuk]

Equal length headers equal loss of burble but good if you have a loud exhaust and want to tone it down a bit lol

Chris

[scottishtaffy]

Fck me Bryan, was that English or an arrangement of words?

lol

:censored: :censored: ive just noticed they are equal. never noticed that before .i thought the n/s ones went straight in but they dont............ :censored: right will have to see about puting the standard one back on and do likde lewis said and get a trick up pipe

[scottishtaffy]

i just checked on ebay from where i got these and there sold as unequal lengh but looking at the pic above i would say when you straighten the pipes out they could be equal its a japspeed exhaust

Edited October 10, 2013 by scottishtaffy

[lewisscoob]

The ones in the pic above look unequal to me. The run from the RH head looks a good bit shorter than the run from the LH head..

[scottishtaffy]

thats what i always thought but youve heard mine lewis and its not got the flat four rumble. . think i will be going back to the cast standard headers

[lewisscoob]

I may have a set here with the collector being ported to Harvey spec...long story. You could port the rest yourself to match the collector? Then just a trick uppipe and robert's your fathers brother. You are planning a remap anyway, right?

[Bryan d]

Lol should really pay more attention when posting loon lol was a bad day and kids wer doin ma heed in lol

[scottishtaffy]

nah phill. would like to sit around the 350 mark and that will be me happy. if i want more i would do what i thought of doing when i went to see lewis's ra, buy one with more powere already. i have noticed since putting on the japspeed that i do have have a slower boost up now. i thought it was the ratiois in the box when i did it up but thinking about it it was a slower spool before i did the box. so think i will just have to bite the bullit and go thru the rigmapole of changing headers again

[sti and]

Most important question of all Alun, Does it still spit flames

[scottishtaffy]

aye after a thrash it spits 3ft fire ball as witnessed by my 2 sons that nearly s**t themselves and then it still spits the normal pops and bangs under normal conditions lol so now your making me think i might just bkeep the japspeed on now lol

[lewisscoob]

It's not the japspeed causing the flame. It's your fuel/timing...

[scottishtaffy]

aye i know lweis. matthew at wallace said at the last rr i went too that it was overfueling up to n5 k rpm then starts to run a bit lean. but was told its a safe power at the mo just dont go doing track mdays lol. new map and ecu with pump , fpr, and 550 inj once i getrid of the 440 i have will cure it all

[mugs]

I was reading somewhere (I'll try and find the article) that was talking about the SS unequal headers and saying they tend to have much less of the burble at tickover and sound like a superbike at higher revs, more like equal length. if I find it, I'll send you the link.

[scottishtaffy]

thats seems to be the case with mine . found my oe headers just need an up pipe now

[lewisscoob]

I'm sure you know my feelings on up pipes...

[oj 89]

I'm sure you know my feelings on up pipes...

Repeat for a newer member? I've been loving this conversation! Haha.

[scottishtaffy]

:rotfl: :rotfl: