Which most subaru owners own too.....

Never mind, if you would rather everyone thinks that and have a poorer performing slower car. Your choice. Maybe you need some wing stiffies too...

 

I prefer having the extra torque, to a burble that does nothing for performance

 

Reading through related threads on SNet there seem to be mixed results and opinions regarding the power aspects of equal v unequal. Twin scroll turbos are a quite different subject.

 

I don't think that's right at all?

 

Which bit?

 

Twin scroll only works with equal length and twin scroll is better

Therefor Equal Length is better

 

There's plenty on torquey diesels out there that might suit you better

 

We're losing track here. The OP asked whether equal or unequal was best in regard to a standard turbo, not a twin scroll. That's not clear cut at all.

 

Best as in best performing or best sound,

Performance is actually measurable,
Equal length is better more efficient,

Differences on a stock turbo may not be noticeable to your bum dyno,

Sound is purely personal preference can argue that all day long between yourselves but no denying which is the most efficient and effective system,

 

I'm not arguing which is the best setup for performance, but sound.

Subaru build the car with a unequal length manifold, to slow the car down? to create the boxer burble? I doubt both of those, but at the end of the day i prefer the burble over abit more claimed torque.

I'm sure Subaru have good reason for having 2 shorter pipes, for example less engine revs required to get exhaust gases to the turbo, so you'll see quicker turbo response with unequal length manifolds.

Maybe unequal length manifolds have slightly other benefits, but nothing that would want to make me loose the burble.

 

" for example less engine revs required to get exhaust gases to the turbo, so you'll see quicker turbo response with unequal length manifolds. "

Bollocks,

There's a reason all good JDM cars use Equal.


not "Claimed" torque either it's been proven,

If you like the noise and not performance then buy a turbo 2000 lol

 

Subaru in Japan fit the equal length headers and twin scroll turbo to their cars as normal.

Just like they don't fit the chocolate 2.5...

 

Educational Video

 

Got one as a daily, next....

 

This is what I meant paben.

It isn't some people have had x or y successful with uel and ul. It is proven and backed up that equal offer better performance.

Spools faster
Holds boost better
More peak power
More torque
Increased power throughout the Rev range

People spend thousands on their car and over look a relatively minor expense that yields massive gains.

Seems stupid to me. Especially when people only do it to keep the ridiculous sounded

 

Ok, apart from all that, what have els ever done for us?

Seriously, this is an interesting topic and begs the question: Why do the Japanese send us cars with unequal length headers and keep the good ones for themselves? Just a cost saving?

What are the likely power gains, making the change, for a 2ltr car running 460/410 with unequal pipes? And presumably, like the unequal versions, not all equal manifolds are created equal?

 

Just changing manifold to Equal Length and a map wont be night and day the differences will be slight,

But all in favour of the Equal Length,


Any 2.0 at 460bhp won't be on boost till at least 4000/4500 rpm

Any tiny gain in spool would be helpful and this is what Equal Length could help with,

I would only go to the hassle of changing if i was going twin scroll as the cost involved for manifold and map wouldnt make sense.

2.0 single scroll 460
2.0 twin scroll 460

Two different animals

 

So the real world answer, assuming a single scroll turbo is retained, is that you might as well enjoy (or endure) the boxer burble and forget the minimal power gains from equal length manifolds.

 

Incorrect again lol.

SmurfyBhoy isn't right at all.

Infact paben you hit the nail on the head. Not all equals manifolds were created equal. **** manifolds won't help anything. Decent ones make a night and day difference...

Circa 35hp at slightly less boost with a 500+rpm improvement on spool and no drop off of power after 6k.

Coming from somdone who has had gt specs , rcm, Jap speed etc. Went from UEL to DECENT EL and the car is night and day to drive compared to UEL. I would never go back to UEL

 

I think ooh the local drug dealer is off on his rounds

 

Hilarious

 

Are u saying there is 35bhp between
Gtspec equal length. And gt spec unequal length ???

I was saying if they are of the same quality. Ie. Both gt spec.
Or both stock.

Not gona be 35 bhp ???

Although if u have a 2.0 at 460bhp it certainly wont be stock.

Yea u could maybey get those gains if going from stock to gt spec tho.

Of course best would be a set of killer bee equal length but they are special

 

I'm not convinced that a 35bhp gain is possible even on a high spec car. I went from a Harvey ported manifold, up pipe & 2-1/2" TB exhaust at 425bhp to a gt spec version and 3" exhaust TB to gain just 15bhp. The biggest power hike then came from the turbo upgrade.

I know that tubular manifolds don't survive long, £600+ up in smoke. Decent quality equal length probably cost more but how long do they last?

 

I have just bought an equal length manifold.

one reason to get quicker spool and slightly more power. The second reason was reading on a lot of the American forums some people put the unequal manifold down to one of the reasons for ringland failure with cylinder 4 having a longer run than the others and getting higher EGTs

 

Considering that is what I got when i fitted my EL headers, then yes it is possible, and yes it is as claimed with proof.

Bare in mind my car is a genuine 500+hp car on pump fuel. I went from 485hp on pump fuel and no chance of cracking 500 without meth to easily producing over 500hp without meth just by fitting EL headers. (517hp in the end

I would also point out that your up pipe is too big...... Which will slow exhaust gases into the turbo.

Yes this is the downside of UEL, it does nto distribute heat equally and matching the exhaust pulses will improve spool no end!


I went from UEL GT/RCM/Tomei (what ever brand they are all the same thing) to EL and went from 485 to 517hp. So it has been proven and like i said a DECENT set of EL manifolds out preform anything UEL by quite some margin.

 

id also point out that GT spec equal length are not equal length manifolds.....

 

some examples of equal length manis here, I agree with J's assessment about equal length manifold and how they perform.

https://www.rallysportdirect.com/scp...-and-manifolds

 

YES They do fit the 2.5 in some models

 

Bloody hell never realised they gave that much of an improvement in power

 

I have a harvey pipe with my gt spec unequals.

You think id get gains going equal on my single scroll sc42 ?

What manifold with what turbo J ?

Was it the same mapper who got you 485 that got you 517 ???

And was this on a single scroll ?
How much would your bum dyno or printout say spool improved ??

Is your car 2.1 ?