with TD and test pipes/hfc you may lose some low end torque but if you get a plenum spacer and gears it basically solves that problem.

 

So why didnt you get the HKS? Its not a 2.5" td...

 

REALY ,in fact thats my next mod 5/6" Iso thearmal pleanum spacer ,about the gears no can do i`m A/M .
and about HKS i don`t want to lose the stock look ,if i didn`t get what i`m looking for with reset, tune and spacer i`ll go with nismo (they fix the cracking issue with some brakets in the joint of the Y pipe)
the pic is from gsingh350Z thread about his new nismo exhaust ,and the sound is so beautiful

 

if you're a/t then just swap the pumpkin with an manual (find someone going FI they'll gladly want the longer gearing). It's one of the best bang for the buck mods for an auto. Better yet get the 3.9 gearing and you will def feel the quicker acceleration.

 

I couldn't make sense a word of what you wrote, but it doesn't matter because I wasn't even talking to you. Did you own an "Exhaust Depot" exhaust? No. So shut up and pay attention next time.

 

mm my fault, sorry for that
cool

 

I think the major issue here is not really dual or not dual. It's the flow characteristics. Personally, I think 2.5" dual exhaust is too big for the stock or mildly modified Z. The pipe is just way too big on an NA car to produce good gas flow in low RPMs. I think if you can find a dual exhaust with 2.25" diameter, that would yield best low end/top end combo. Exhaust has to be correctly matched to the application it's going on. If the pipe is too big, you will loose low end because the gas velocity no the exhaust side is too low to create good scavenging effect from the intake. This is why you see the losss of low end torque. The nice thing is that a big exhaust has better capacity for high flow when the RPMs are high which gives you good top end. If you make the pipe small, you get good flow in low end thus maximizing the effect but the exhaust will choke the overall flow when the RPMs are high and the car will fall flat on its face up top. Is there a dual exhaust with 2.25" diameter?

Theoretically, going with dual is more optimal if you can get the right size. The more you isolate all the runners, the better. Ideally, each collector would have its own full length exhaust. That would be cool BTW, I think this has been said already: backpressure is never good. I don't know why people think you need that on an NA car. It's all about the flow.

 

Ziggyrama,

I believe the HKS is 2.36" td. That is probably one reason why many vote that it is the best td on a na z.

 

Good deal. I have not seen every exhaust out there but it seems that most advertise 2.5" diameter. Sounds like HKS did their homework then. Any other that are roughly that size?

 

What a load of crap!!! of course you can run a 3'' dual on N/A cars!!!!!! what the hell do you think most muscle cars do that run open headers!!! me is thinking there is no back pressure there what so ever. i had a magnaflow cat back 2.5'' bore was ok, then tried a APS 3'' true dual 1. they sound awsome,2. the car never felt like it lost power just felt free in the rev range. You cant go around saying that you will lose this and that on o exhaust because all engines are different there not made to the same spec there MASS produced, this bloke losing power could come from anything as simple as a idiot fitting it wrong i.e. lose bolt or anything

 

5 months ago dude...

TK

 

FAIL

 

It may be five months ago but there still on about the same crap!!!!!!

 

lol

 

I added a true dual system on my n/a Z and it dropped my 1/4 mile time by .3 tenths and gained 2 mph.

 

wow, a 5 month old thread made u that mad? way to save the day lol.

 

2.5 Single exhaust for n/a
3.0 Single exhaust for F/I

Single exhaust just wins them all

 

What system?

 

im happy with my HKS wannabe

 

My nismo exhaust is 3" single also, good enough for n/a.