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Big Mistake By Instaling 3" Xforce System In To My R33 Non Turbo

SkyKC

By SkyKC,
in Engines & Forced Induction

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lighty01 Collaborator

lighty01

Posted
Posted

your probably loosing most of your bottom end power... but ull probably feel an increase top end..

U dont have to change your whole system.

Y dont you change your front pipe to a 2.25inch system.

the rest can stay..

if you restrict the flow in the front pipe, the cat/catback wont really matter as much.

that way you will keep your "cool" sound plus get some performance back.

PS. i have a 3inch xforce system on my gtst 33.. LUV IT

GTS4WD Grand Master

GTS4WD

Posted
Posted (edited)
Eug, what do you mean?

Correct me if im wrong Eug,

The term is "volumetric vacume" or "volumetric efficiency"

I.e

If the pipe is too big.. the exhaust just lingers around and doesn't exit the exhaust piping in the most efficient way. Too big of piping can result in worse performance than stock.. as you found out.

If the piping is too small.. the exhaust fumes struggle to fit through the piping and the flow is choked and slowed as there is too much gass exiting the engine and the piping cannot cope.. again.. hindering performance..

With the right size piping.. the exhaust gass will flow evenly.. and create a form of "vacume" where by the gas will almot accelerate in "speed" throughout the length of the exhaust sytem..

Its a simple explination.. but I hope it gets the point accross..

back preassure is when, for eg. you have a turbocharged car without an evacuation system (Blow off valve). So when you take your foot off the accelerator.. the turbo continue to force air into the intake manifold. Because there is no were to go for the air to go.. it will build up.. forcing itself back down the intake, creating back preassure. This preassure will slow the turbine of the turbo down. When you eventually get back on the gas after changing gears.. you will have to wait for the turbo to spool up to its previous point (before the back preassure began to slow the turbine down) to continue making power..

thats the diff..

On the subject of xforce.. I drove my car with only exhaust mani connected.. I think it was quieter than with the xforce cat back I used temporarily.. I was willing to drive my car into a wall just so as to not hear the exhaust after 10 min of driving the thing..

Edited by GTS4WD
Eug Grand Master

Eug

Posted
Posted

that's pretty much it in a nutshell Cris. good man

on what you said with smaller piping, that may cause back pressure also. just by breaking down the word literally should be more than enough explanation.

Eug, what do you mean?

if you have posted in here, there is no need to PM me. i will see your post in due time.

He's said it many times in many threads now :P

good man, into the good books you go :whistling:

SkyKC Rising Star

SkyKC

Posted
  • Author
Posted

HEy guys, (I couldnt wait)

All done, today I went to Liverpool exst 9.30AM hehehe and was there until 1pM, got a custom 2.5 system installed with Hurricane 2.5in muffler(4.5 tip) with silencer, and the rest of pipe is 2.5 mild steel. I drove home without the silencer OMG...........felt like shooting my self, so much noise hehehe :) , but I could feel the pickup speed better than 3in one. now I drive it with silencer, which is good, nice beat........(But not nice as xforce I have to say)

Guys thanks for the explanation of back pressure, I really appreciate it.

Now I have to sell the xforce system soon, so I can pay my cc :D here some picture of my new cat back system........... :banana:

Thanks heaps guys.............

post-33178-1203308365_thumb.jpg

post-33178-1203308504_thumb.jpg

post-33178-1203308567_thumb.jpg

SkyKC Rising Star

SkyKC

Posted
  • Author
Posted
Y dont you change your front pipe to a 2.25inch system.

the rest can stay..

mmmmmmmmm good idea tho, now at least I can advice this one to someone else, cheers

SkyKC Rising Star

SkyKC

Posted
  • Author
Posted
My Varex XForce muffler arrived today, she's beautiful. I took the 2.5" inlet route too, with a 4.5" cannon. Will post some videos once its installed.

wow thats nice, is this the one with controler, that you can change the tone? if so how much was it and where did you buy it?

Cheers

KezR33 Veteran

KezR33

Posted
Posted
wow thats nice, is this the one with controler, that you can change the tone? if so how much was it and where did you buy it?

Cheers

$350 + $25 delivery from ebay. From this guy; http://myworld.ebay.com.au/x...f

I don't know if you can change the tone so much, just the volume. It's a 4.5" cannon that can be opened fully or completely sealed so that the air has to travel along another path which leads it up and down the muffler several times, dampening it significantly. So you can have it loud enough to hear from 4 blocks away, 2 blocks away, just down the street, or quiet enough to sneak by the police. Well, that's what I'm hoping anyway.

It's a lot better than I thought it would be, wires come with a fuse (on easily replaced) and a cigarette lighter jack. Plan on wiring up a cig lighter port off the battery into my boot this weekend and getting it installed during the week.

Your current muffler is an Xforce one correct? This one will just bolt straight onto your current exhaust system if you're considering it.

SkyKC Rising Star

SkyKC

Posted
  • Author
Posted
$350 + $25 delivery from ebay. From this guy; http://myworld.ebay.com.au/x...f

I don't know if you can change the tone so much, just the volume. It's a 4.5" cannon that can be opened fully or completely sealed so that the air has to travel along another path which leads it up and down the muffler several times, dampening it significantly. So you can have it loud enough to hear from 4 blocks away, 2 blocks away, just down the street, or quiet enough to sneak by the police. Well, that's what I'm hoping anyway.

It's a lot better than I thought it would be, wires come with a fuse (on easily replaced) and a cigarette lighter jack. Plan on wiring up a cig lighter port off the battery into my boot this weekend and getting it installed during the week.

Your current muffler is an Xforce one correct? This one will just bolt straight onto your current exhaust system if you're considering it.

Wow thats cool, I had xforce 3" system which i replaced with 2.5" hurricane system...........Pls post some pics of your system once you install it, I certainly condier getting one of those :thumbsup:

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