anybody on the board running it? heard any reveiws? how you guys think this will improve performance, sound. any pros and cons to running this monster. just trying to get some input before i purchase.



http://www.apexi-usa.com/exhausts_gtspec.asp

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33630&item=2419279997

DWAYNE H

www.gottude.com
Red/Black/Silver 01 GSXR 750
Lots of Apexi components...

according to apex's website, they dont make it for our cars or gst

click on the ebay link above, its avail for the gst and gsx

DWAYNE H

www.gottude.com
Red/Black/Silver 01 GSXR 750
Lots of Apexi components...

my buddy has the GT spec on his 240... it was nice pre and post SR20 swap.... sounds great too.

Wider is NOT always better when it comes to exhaust, even with turbos. 3.75 is really huge, expect to loose a good chunk of low end. There's also no gaurentee that you'll make it back on top end.

Of course, your peak horsepower may be drastically higher, but will your overall curve be better? It's stuff to think about, you may be disappointed.

im 2.4, the 2.4 are notorious for there torque under boost. this is also another factor to consider.

this exhaust will see stage 4 + boost levels, you think there will be any downside becuase of the width? all input welcome :thumbsup

DWAYNE H

www.gottude.com
Red/Black/Silver 01 GSXR 750
Lots of Apexi components...

my buddy has it on his. the thing is huge!!!! i thought my buddies 3 inch on his tanabe was big but this is just huge. sounds good and all. he is doing 400+ hp so i know he needs it.
later

a little more input on this please, dino what you think? Murix what you think? aRmond30, what you think. high hp guys help me out. the1bill, tell me something?

you guys give awesome knowledge on stuff like this, downsides and pros, so input please!

DWAYNE H

www.gottude.com
Red/Black/Silver 01 GSXR 750
Lots of Apexi components...

Look again man, they just say that is the biggest Apex'i can make exhausts, thats not the size of that one.

Pipe Diameter: 70mm-74.7mm-85mm

95mm=3.74"

im thinkn in some flexpoints, it might drop down to those sizes. im not worried about that, i will confirm that before i order :thumbsup. im inquiring about the magnitude and characteristics of this running tthe 3.74 inch exhaust

DWAYNE H

www.gottude.com
Red/Black/Silver 01 GSXR 750
Lots of Apexi components...

i bet it would be kind of loud, but whatever. it'll be worth it.

about having "too big" of an exhaust on a turbocharged car, i've come to the conclusion that backpressure on a turbocharged car is 100% the devil. i've heard of people loosing torque on a N/A from having exhaust too large, but i've NEVER heard of anyone with a turbocharged car loosing power becacuse of exhaust that's too big. imaging having nothing at all after the turbo, boost would set in so much faster. boost = torque and horsepower.

then again, for "backpressure" before the turbo, having 3" units coming out of each of the cylinders would be kind of stupid. velocity would be slow, and everything would be fubar. having some type of laminar flow iris (NOT a throttle plate) that reduces the diamater of the whatever a little to increace the velocity of exhuast gas at low RPM's to speed up spoolup, then opens up high to optimize exhaust velocity would be sick.

I know that when the turbo is spooled, the 3.75" will be awesome, but what about those times it's not spooled? When the turbo isn't spooling or fully spooled, it will basically be like you're riding around in an NA car with 3.75" exhaust. That can't be good.

I'm sure going in straight lines, you'll see great results, but what about those turns where you have to brake til the turbo stops spooling and then accelerate? How will the car feel then?

The only real good way to see what'll happen is to try it out, maybe dyno before and after. But, unfortunately that's alot of effort. The whole original point was to just throw out that wider isn't always better. :thumbsup

the motor alwasy has back pressure for before boost runs because of the fact of the turbine being in the way anything after the turbo that isn't *toooo small* will never hurt the car most cars (turbo) will run better with no exhuast period cause there is no restriction...

with the 2.4 high boost levels and the mods that u ahve i dont see it as being any problem but getting around the tight spots where the exhaust has to run...

Bill

i plan on atleast 3.25" all the way back...

>I know that when the turbo is spooled, the 3.75" will be
>awesome, but what about those times it's not spooled? When
>the turbo isn't spooling or fully spooled, it will basically
>be like you're riding around in an NA car with 3.75" exhaust.
>That can't be good.
>
>I'm sure going in straight lines, you'll see great results,
>but what about those turns where you have to brake til the
>turbo stops spooling and then accelerate? How will the car
>feel then?
>
>The only real good way to see what'll happen is to try it out,
>maybe dyno before and after. But, unfortunately that's alot
>of effort. The whole original point was to just throw out
>that wider isn't always better. :thumbsup

no, im sorry but you still dont understand what the man was trying to explain to you. you might not own a turbo yet but if you ever plan to like most of us, you better hit the books. if your turbo car has a dramatically huge exhaust system, or a non exsisting exhaust system, it will dramatically change the characteristics of your turbo's functionality. for example, a little t25 usually reaches full boost by/before 2.5k rpms. which means, it starts building up boost almost immediately after you punch the gas. theres no time for your turbo car to act like a weak na car with a giant exhaust. if you have a huge exhaustsystem, or none at all, a little t25 will simply be making more boost that much faster and giving you that much more torque/power that much faster which will all in all make you, yes THAT MUCH FASTER. :-)

now show me one person on this board who doesnt want to go faster, don't hold the madness back!!!!!!!!

with research and some input from u guys, i have made my decision, im gonna go ahead grab one, and ill the turbo guys know how it goes. wont be for a month or so though. . i was hoping i would get a respnse from dino or armond. or well, thanks though

well, anymore input would be welcome.

DWAYNE H

www.gottude.com
Red/Black/Silver 01 GSXR 750
Lots of Apexi components...

>no, im sorry but you still dont understand what the man was
>trying to explain to you. you might not own a turbo yet but
>if you ever plan to like most of us, you better hit the books.
> if your turbo car has a dramatically huge exhaust system, or
>a non exsisting exhaust system, it will dramatically change
>the characteristics of your turbo's functionality. for
>example, a little t25 usually reaches full boost by/before
>2.5k rpms. which means, it starts building up boost almost
>immediately after you punch the gas. theres no time for your
>turbo car to act like a weak na car with a giant exhaust. if
>you have a huge exhaustsystem, or none at all, a little t25
>will simply be making more boost that much faster and giving
>you that much more torque/power that much faster which will
>all in all make you, yes THAT MUCH FASTER. :-)
>
>now show me one person on this board who doesnt want to go
>faster, don't hold the madness back!!!!!!!!

Except from Forced Induction Performance Tuning by A. Graham Bell. pg. 122.

"Even seemingly unimportant things, such as the size of the exhaust tailpipe, can stifle bottom-end power. I recall one Nissan racer...The problem in his eyes was the 3in exhaust reduced down to 2.5" just before the rear axle. (Demanded 3" rear section)... A week later he was back, cap in hand, begging for the original 2.5" tailpipe. The reason for his change of heart was that the big tailpipe didn't deliver any power gains, and worse, the bottom-end had 'disappeared' and the mid-range was 'hopeless'."

So, i have been hitting the books. I just threw it out as a friendly warning. Inevitably I can't say for sure cuz i don't have personal experience, and I didn't know he was going to use a t25. You can agree i have a valid point if say it was a s25g or something right? But, i'd think a tiny t25 would max out before needing that much exhaust flow.

edit: I'm not arguing that you're wrong, just defending myself for you saying that i should hit the books. I'd love to hear the technical reason why you think a free or open exhaust would be best for a turbo when this author has stated it's not always best (i like hearing both sides)

mystic think t25- doesn't really need anything bigger then 2.5 that is what the nissan racer is usging in that statement think super 20g ona 2.4 BIG difference in flow and turbo sizes there....


on a t25 system i would never recomend an exhuast that big it would do exactly as corky bell stated...

ona 20g with a 2.4 and as muh crap as me and dwayne are doign to the 2.4's i think it could have a performance gain...

supra guys are now running 4-6" exhuasts with their massive turbos...

Bill