V8 & Twin exhaust question

[Wildsupra]

Just wondering if there is any reason why a V8 couldnt run twin exhaust without a common collector anywhere in the system, E.G. can i run one system off one bank of cylinders and the other system off the other bank.

For some reason i keep thinkin i heard somewhere that it needs to become common somewhere in the system, but i cant really see why.

Would certainly help narrow down any misfires if i kept em seperate

Cheers
Matty

[Billzilla]

Yep, you certainly can.
I don't know all the little tricks, but most run a balance pipe a short distance after the collectors.
You can treat each bank of four like a seperate engine, but the 90deg crank of the V-8's has the extractor pipes in either the traditional 4-1 or if you go 4-2-1 then the end two ports have to join each other first, then those two secondaries into the final collector.

[joecoolmk2]

aren't balance pipes etc there to keep even back pressure on all cylinders or something?
they must have SOME purpose for everyone to put them in the system....


EDIT: googled it and found this: http://www.binderbulletin.org/faq/8.htm

so it says, they reduce noise, eg. exhaust 'drone', and they apparently improve low end torque. the torque improvement would have something to do with back pressure and pressure waves i reckon.

[MRMOPARMAN]

on alot of modern v8s (eg my au etc) the duels merge into one then continue to the end before slpitting into 2. im pretty sure that for $$ and space restraints. you can run duels all the way back without a crossover pipe but there can (and usually is) gains to be had by fitting one in my experience

[Wildsupra]

Bill your post confuzzled me, did you mean i do need to send both banks to a common collector first or not?

I assumed the back pressure theory had something to do with it, but then wondered if it wouldnt matter cos its using 4 cylinders per system anyway.

Its looking like a crossover might be the better option then.

Cheers

[2jzhilux]

the balance pipe makes it sound better too
had a v8 without one and it just sounded like a fart can

["Z" UTE]

I dont seem to recall too many top fuel drag cars using a crossover !!!!!

The old school V8 boys all used to run separate dual pipes. For instance the "Lakes" pipes down the side of bucket "T"'s.

The V8 super cars actually use a crossover, and you can bet it is not for noise suppression, these guys are chasing every millipoofteenth of horsepower they can get.

cheers Chuck.

[EldarO]

twin sidepipes...

on each side

you know ya wanna.

Elmo.

[roadsailing]

balance pipe helps, well balance the engine out.

it you had a flatplane crank V8 you can treat it like two 4 cylinders, with a cross plane crank you can treat it like two really garbage uneven firing four cylinders.

as others have said, a balance pipe will make it run better and sound better, why do it the wrong way?

[orange_23]

The balance pipe on my dual system is purely to quiet the thing down. Most warmed up v8's that i know dont run one, i've heard you get better flow without it.

[Robbos_Toyotas]

your balance pipe, if you have a motor worth spending this much on, will provide you with more torque and more even backpressure. I run one on my supra with its twin 3" system.

[mrshin]

Balance pipe = good thing. Try running an engine without it, especially a 1UZ, and they sound dreadful - sort of like a V8 4AG. However, the more important side of it is that they do indeed act like the 'tertiary' part of the headers, and therefore there is an art to tuning them to work properly. Many exhaust places just throw a piece of pipe across the two other pipes anyplace they feel like - this doesn't always do the job anywhere near as well as it could. Try and look at a V8 supercar one sometime, they're not there just to look pretty.

[Robbos_Toyotas]

ill try and get a pic of my system, they blend the two systems together when they do it properly. The easy was out is to just install a "H" pipe...which is what a lot of cheap installs do.

[JustenGT8]

Individual UZ twin systems sound shit...i mean really shit. They sound shit on pretty well any V8 other thana flat plane crank but for whatever reason the UZ sounds particularly bad. Use a proper X-pipe and you'll lose no flow, may see some gains and at the very least it'll sound so much better.

Personally, a big single system makes for the best sounding V8 in my book. A much more sophisticated sound (if you can describe a roaring exhaust as that) but maintains the ballsy menace a V8 should have.....kinda like a huge tatooed maori in a nice suit

[BeRad]

a mate whos into v8s showed me this handy trick when it comes to positioning your cross over pipe, run a colored crayon down the side of of both systems, as the exhaust heats up mark the first point on each side that melts the crayon first, run a crossover pipe from one side where the crayon melted first to the other side where the crayon melted first on the other side, weather these are 3 feet down the car from the other this is the best position for the cross over, this provides the best flow for a twin system, makes sense too