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What I don't get is that both systems put out pretty much the same HP so in theory, does that mean 2.5 and 2.25in is neither good or bad? Believe me I'm a full believer in the PTS system, I've had it on my 06 and it was thee #1 exhaust IMO.
I'm just trying to see what would benefit my SC later...
Pipe diameter is one of the parameters to consider when designing an exhaust system. A system with 2.5" and piping bends and restrictive mufflers could perform similar to another with 2.25" and more straight pipes + high flow mufflers with low restriction. Additionally, a larger diameter pipe + less bends and low restriction mufflers doesn't yeld the best result, as some back pressure ( restriction) is needed for the engine to give its best performance.
I was pretty sure you knew the FULL Catback system would be the same 10-12 RWHP gains on the IS350 since its the same motors we tested back in 2008...
Also the definitive answer was 2.5" piping is too large on a full true dual exhaust on a V6 motor..
2.25" piping is the correct size for measurable performance..
We properly use the 2.5" piping for our V8 exhaust platforms which include the IS F, RC F and soon GS F..
Hope this helps clarify your questions
Joe Z
Joe Z,
Some feedback for you. We greatly appreciate the information and explanation on your engineering.
Bringing it back from the dead. But I've tried searching for JoeZ's dyno and found nothing. Anyone have info if it makes power or not? Considering that Ark is 2.5in and JoeZ is 2.25 there should be better gains with Ark IMO. I've asked JoeZ why he didn't go 2.5 and no definite answer ¯\_(ツ)_/¯
We tested both size and 2.5 was the better choice, the stock midpipe is already very close to 2.25, but tapers down to a smaller axelback.
We got pretty good gains as you can see from our dyno Richie already posted.
Here it is again
Last edited by ARK Performance; 01-27-16 at 01:51 PM.
We have been making exhausts for a very, very long time.. Especially on the Lexus IS350 platform..
So we know what works & what doesn't on V6 motors
Below is our original R&D independent testing results from the 2006 IS350.. (w/ stock intake)
At the time we had Two versions..
One Street system w/ High Flow CATs and One Race System without Secondary CATS..
We now only offer the RACE performance system without secondary CATs.
2.5" is the perfect set up for the V8 -> IS F / RC F / GS F motor
Regards,
- Joe Z
Bring up an old post so basically from both of the graphs they both make similar power 2.5 vs 2.25 diameter piping but I’m guessing the 2.25 makes more power under the curve ???
01-11-16, 01:30 AM
