What is the optimal EXHAUST size for daily driving?

EDIT: Posted in the forced induction thread so this would be for a turbo application.

 

by this your meaning exhaust piping right?

 

From what I've seen and read, 2.25 is usually for NA applications. Go 2.5-3" if you're going turbo.

 

2.5in max. Im sure a debate will start in this thread so prepare for pages of fighting.
And Im sure Ill be included.

 

ooooooops
you have to make it more clearer when asking
i chose 2.25 thinking NA

but 2.5 should be fine for our HP range with a turbo

 

the maximum HP you'll get out of this car turbo'd is 200hp.

2.25" is plenty for 200hp, promise.

 

turbo's hate post turbine backpressure. 2.5in+ faster spool and mo powa!

 

guys 2.5 can flow up to 400 hp. 2.25 would be more than enough. I would be inclined to think that you could even reach 200 hp with 2 inches like the spoon or a spec

 

first of all, i just wanna know what he's talking about in size, intercooler piping or exhaust piping, it wasn't really clarified. In either case 2.5 inches should be more than enough, intercooler side wise, the extra volume could cause a little lag for turbos, same could be said about having a big frontmount intercooler as well

 

Does anybody know what the I.D. is of the stock exhaust system?

What is the I.D. of the outlet/down pipe on both kits?

What dictates the optimum diameter piping for exhaust flow of an internal combustion engine, power or displacement?

I'm thinking 2" will be just fine for my little 1.5 that is well under 200hp.
I don't want to be associated with the "fart-can" crowd.

 

I believe the factory exhaust is 45mm. That is 1.77 inches.
50mm is 2" and is plenty for a 1.5 liter under 200hp, turbo or not.

This is my Honda Fit, not a race car.
That said,I think I will go with:

T1R B-Pipe and a custom Magnaflow 2" painted black similar to someone else who had their system made by LHT Performance.

The HKS turbo kit and a light black coat on the intercooler.

Retain factory wheels

Upgraded shocks and keep the stock springs as they are.

Strut-tower braces and upgraded sway bars, if available.

*** I want nice flow, minimal sound, stock appearance, and just enough power for my
driving.

I miss my '90 Nissan 240sx coupe but I don't miss the transmission and other headaches.

 

Would there be more, less,or same lag if you had a 2.25 vs a 2.5 exhaust for a turbo?

I'm asking because I do A LOT of short city driving....

 

can flow, would be inclined to think, you could......

these r not words to use to answer a question with absolutes like best

i.e. u could run a marathon breathing through a snorkel
but..... it would be best not to do so

"more than enough" - what is enough? what is adequate? do we even need a car?



for a turbo infinite diameter is best


"more than enough" - those r fighting words!!!

 

more. almost same but still MORE

 

Are you talking Cat back? If so I would go for BIG pipes, 2.5 definitely.... Larger pipes at the exhaust ports will kill the low end power due to flow velocity loss and exhaust reversion..... Stepping the pipe size from 2.25 at the mid and 2.5 axle back could give more flow velocity, be better at the lower end, result in less lag and not hurt you at the top of the power band noticeably. I wouldn't get a mid pipe that doesn't have a resonator unless you want to be labelled as a ricer though the turbo itself is a pretty good muffler.

 

VERY sound logic there. Thanks for the info....Does anyone know the size of the HKS or Greddy down pipes? I emailed Greddy and the HKS tech guy would NOT give me the info....odd....