nope not the same as my op. because im actually looking to take peices from all of those posts n put it into one, kinda. im looking for hard evidence upon lots of other things

just a few about cheap exhausts n buschurs exhausts.

 

lol

but in all honesty, the hks cat back is like 2.75 or less. and VERY heavy.

 

I dont doubt you, but dont let someones opinion of something make you change your whole setup. Thats crazy.

Do indepth research. Its funny cuz if you look in one of those soda can threads one of the exhausts the guy was hyping up didnt even pass his own test.

Just read and research and try and wade through the BS.

 

this is true.

maybe not change my WHOLE setup, but maybe just my cat back? and keep the Megan Dp/TP

maybe get an AMS catback?

 

so go from 3" DP to 3.5" catback??

 

no no no, a 3" ams catback

if i were to do 3.5" id do a full 3.5" turbo back..

common now man, im not a newbie, nor an idiot

 

bump for some information!

 

The weight issue is silly because 10 pounds is pretty meaningless especially when its at the bottom of your car.

Your not packing 10 pounds into your headliner, you should be fine with a true 3 inch exhaust with minimal bends.

I think 3.5 inch would be a good idea if your snail is bigger than a gt35.

 

I chose 3.5" custom built for my IX. I also feel that 3" is probably good for 500-600whp. If you plan on going above that, then my opinion is go bigger. Don't ask me why, because it's only gut feeling and a few years of experience.

 

There are "scientific" ways of figuring this out.

The ONLY reason why I would ever second guess the 3.5" exhaust is the weight difference.

 

I understand about the scientific ways, but my unscientific comment was too keep the scientific naysayers at bay. Volume of air coming in, temperature rise, velocity of air, etc, but I'm not into scientific calculations, I prefer the swag method and prayers.

 

And you're correct about the weight, but you still have to assume that you are going to continue to tune and improve an engine over time. As modifications continue and whp goes up, the 3.5 should not be a limiting factor at that point. It's not what the gain is currently, but what it allows you to build to later. I have made great weight savings investments such as 4 cf doors, deck, cf seats, and many more, but I felt that the weight added was more than offset by the whp to be gained over time, through other modifications both known at this time and unknown.

 

hey eric, if your willing to send me one of your turbo back goliath systems ill be happy to dyno test the differences between a few exhausts

 

I kind of understand where your coming from, and althou u do have a valid point, i think there should be some crazy extensive tests done between a bunch of different exhausts

 

I agree about needing the tests, especially to see if the 3.5 is worth adding the weight, not to mention the expense. It seems reasonable to assume that as volume of air goes up, i.e. horsepower, so does the need to get rid of the air. It never made much sense to me to have a 3" intake and less than 3" on the exhaust, especially when the air is heated to a higher temperature than when it entered the engine.