twin scroll turbo

[rex-leggy]

yea you said that was just curious to weather they are tuned or not . dont even know what tuned means compared to equal and stock exhausts .

for twin scroll there using "turbulence" (dont know what the term would be) to help spool the turbo so a more unequal exhaust in my mind would help alot more .

just thinking out loud here who knows lol.

[WRXONP]

tuned length means each runner is the same length -

tuned length will make more power as the gases flow allot faster and easier to the turbo

the unequel length headers loose power from the 2 exhaust gasses clashing (running into each other if u may) which decreases spool up time and hurts power

thats about as plain as i can put it

the general rule of thumb for pipe diameter is the same as intercooler piping - the larger diameter the longer it takes to fill it up with pressure

smaller diameter runners will spool the turbo faster then big runners

just like those cheap nasty over sized up pipes around

[rex-leggy]

 WRXONP said:

the unequel length headers loose power from the 2 exhaust gasses clashing (running into each other if u may) which decreases spool up time and hurts power

when it comes to twin scroll i would have thought this would help.

i always thought there was a difference between tuned and equal extractors

[WRXONP]

u want the energy (speed) of the gasses to spool the turbine - not slow down by clashing with each other

[tez n u]

Even evos with big turbos (gt35r etc) sound smooth and similar to a subi with tuned length headers if they run tuned length as well.........check out the vids below as an example ;D and not many hondas can sound like the cars below in the vids

evo

wrx

[WRXONP]

Lol street racing !!! Fella got killed twice

How long till the link gets deleted ??

[funkytown]

lol wrxonp - equal length does not equal better spool. its been proven a few times.

[funkytown]

 rex-leggy']

[quote name='WRXONP said:

the unequel length headers loose power from the 2 exhaust gasses clashing (running into each other if u may) which decreases spool up time and hurts power

/quote]

when it comes to twin scroll i would have thought this would help.

i always thought there was a difference between tuned and equal extractors

was my impression as well

[WRXONP]

 funkytown said:

lol wrxonp - equal length does not equal better spool. its been proven a few times.

Re read - I did say the diameter of the runners is what dictates it

[funkytown]

 WRXONP said:

the unequel length headers loose power from the 2 exhaust gasses clashing (running into each other if u may) which decreases spool up time and hurts power

perhaps you should re-read what you wrote. it says DECREASES spool. wrong it doesnt. its been proven over multiple cases that unequal spools as well if not better then equal length.*

*on subbies.

for one your runner lengths are all much longer.

[WRXONP]

Yea well my bad I did write somewhere else about diameter effecting it the most - but the collector style effects spool dramatically - because smoothing flowing gasses that don't clash will increase spool - compare a sinco merge collector to a stock Subaru manifold where it merges

[funkytown]

no worries, i just hate mis information.

be careful when stating a reduction in top end for unequal length. I'm happy to look at back to back comparisons proving the statement but i haven't come across much in that space. That is not also to say that great results cant be had on unequal length set ups like mine and others or equal length setups like Simon C's. I like results to back up bold statements is all - and is more helpful for the masses to make informed decisions.

I do agree collector design, port matching and runner bends are all VERY important, also is the runner diameter and uppipe size and how it affects spool. but applies equally to both.

[PhatRS]

But equal length sounds better so its faster haha. *waits for flaming!!!!

[funkytown]

 PhatRS said:

But equal length sounds better so its faster haha. *waits for flaming!!!!

lmfao - smart arse.

[SUBRMN]

i always thought equal was alot better than standard un equal i went from standard unequal to cheap tuned length huge pik up difference that a personal review

[rex-leggy]

do you have dyno results? would be good to see the effect as to weather the better pickup sacrificed power up top

[Too Broke]

My impression was that equal length headers improved the torque curve?

I love the sound of the Twin Scroll + VVTI + Full noise

[vorigan]

 funkytown said:

lol wrxonp - equal length does not equal better spool. its been proven a few times.

+100

equal length doesn't mean crap they only work best at set point before and after that their a compromise anyone that thinks other wise needs to buy a real book on the topic not net gossip.

the headers on a sub are already too long and trying to achieve equal doesn't gain a lot apart from making it more peaky as such the 4-2-1 is the best all round and if the pipes are +/- 2-3" it doesn't hurt since most out there cant tune individual cly then just live with it.

The head tech man for Audi grp b rally days words on equal length headers was " get over it cause boost over comes all" but as for pipe size well that's different story there stepped headers have great gains.