ISS Forged Exhaust for the Lexus ISF

[meade916]

Check out the new exhaust i have coming for my ISF. Its been 3-4 weeks since this was ordered and it should be here sometime next week. I didnt really want to say much until it was closer to delivery day but i really just wanted to make a thread to show you guys what its all about, and of course some pictures. The four diffuser pipes that are on there now will be removed to make room for the true tips. Anyway, i will make a new post for my ISF but i figured i would post this up for a little teaser to whats going to come!

Stay tuned, this week should be some fun show-and-tell going on!

[meade916]

oh FYI: here is some info on the "X" pipe in the middle of it. (the "H" looking thing you see, isnt an "H-pipe", its just a piece they weld in for easier installation)

Although X-pipes are essential for race cars, adding this modification to a stock car can be a good idea for many reasons – increased power, fuel economy and less noise inside the vehicle. This type of aftermarket performance part is something you can either purchase or have custom-made for you by a good muffler shop. Installation is simple enough for the at-home pro, and the result will be well worth the effort.

The Evolution of the X-Pipe

To understand the importance of the X-pipe in relation to improved performance and power, you have to know about its roots. The X-pipe is really the offspring of the H-pipe design, which was first conceived in the 1960s by the major American car manufacturing companies at the time. Duel exhaust pipes for V-8-powered vehicles are very noisy, as there is no sound wave cancellation between the 2 separate four-cylinder engines and unconnected exhaust systems. Engineers were looking for a way to cut down on interior noise levels and improve the engine's power. They realized that running a balance tube between the two branches of exhaust pipe would work to broaden the torque curve (thus improving engine performance) and dissipate sound resonance in the exhaust system.

In the 1990s improved technological advancements made it possible to construct an exhaust pipe that, instead of connecting by means of a balance pipe at a severe 90-degree angle, could unify the two branches of pipe to create a flow of exhaust in one direction. Now X-pipes are being manufactured for popular performance cars, usually off-road versions minus catalytic converters, but you can also find them in legal models fully equipped with proper emissions equipment. Performing an X-pipe mod is an option that you should consider.

Why X over H?

It has been proven time and again that the X-pipe design is more efficient than the H-pipe. Various tests have shown that for multiple cylinder engines the X-pipe outperforms H-pipe exhaust systems, especially as rpm increases, providing both better torque and power. Unified exhaust pipes work most efficiently with multiple cylinders because of the scavenging effect. With exhaust X-pipes the almost seamless connection between the two exhaust pipes allows sequential firing cylinders to salvage any spent exhaust gases from the combustion chamber more efficiently and creates more room in the cylinder for a fresh intake of undiluted fuel and air. When you have two exhaust pipes, as the velocity in one header tube increases, the pressure in the adjacent tube is lowered causing the exhaust to be sucked out of that cylinder.

All in all, with exhaust X-pipes torque and power will increase resulting in fast acceleration, improved fuel economy and a nice quiet ride. The difference is noticeable with the installation of X-pipes on a V-8 engine vehicle - interior noise is reduced considerably because you don't hear the firing impulses of 2 four-cylinder engines, but instead hear the noise of all 8 cylinders blasting out of both pipes at once.

[kryptonite]

Now she's gonna growl a lot better

[THEKINGsBACK]

So with this ur picking up how much power? Around 30 horses ?

[PUNKYOU007]

Nice. Isnt the dual setup on these cars...a fake? I mean only one side actually functions. Thats a pretty nice increase for just exhaust work.

[meade916]

Nice. Isnt the dual setup on these cars...a fake? I mean only one side actually functions. Thats a pretty nice increase for just exhaust work.

no, none of it is fake, who told you that? God damn some people are stupid. (not you, whoever told you that).

the 4 tips on the back are the only thing that isnt connected physically to the exhaust system, but directly behind them the exhaust which ALSO has four tips, blows directly thru the diffusers. Some people try to call it "fake" because of that, but they are not fake, they are diffusers and LOTS of high end cars have that. As for what you said, "only one side actually functions", that is complete and utter bullshit. This car already has dual exhaust and it all works. Its a V-8 under my hood not a four cylinder lol.

[Purplehaze]

That is gonna sound SO good! X pipe make a difference fore real! You will LOVE it!

[esea1494]

so all it needs now is a blower

[meade916]

so all it needs now is a blower

that'd be sick but i dont think anyone has perfected it for this motor yet. Everything i have read about the few who have attempted it is they dont run 100% correctly yet. Sick as hell but they have problems. I will wait till i get closer to paying the car off before i make major mods like that though. I want to supercharge my Tahoe so i might consider doing that first. I own that ol' girl so no worries there

[tonedeaf]

Nice increase in power for sure. Now smack a brand new turbo in that thing.