Well, I'm speaking from my experience that on MY stock motor it made noticably less bottom end with the collected header and WIDE open exhaust. (2.5" from the header back split into 2.5" duals out with nothing more than glasspacks)

You could be right about the true duals. I have no experience with them.

 

Why is it that the racing beat site prefers to run a carburated setup with headers and a fuel injected setup for the cat replacement pipe and silencer? It says "similar" gains but why even say that...

 

I thinks 2.5" duals is what's killing your lowend Jimmy. Someone mentioned 1.75" as optimal for better low end. Consider the fact that the exhaust port is < 2", any pipes bigger than that is hurtin the scavanging effect.

 

i have the mindtrain on my 90 n/a and it made a very noticeable difference but the power curve remains the same so there are no drastic difference in the way the car accelerates. and by the way: keep it off the streets: for the love of life!
nasa
ncrc
scca
these can all get u on track
GT3 is kindov a dream

 

ebay7, I now have a very ported motor and it made tons of bottom end with the full 2.5" exhaust. 2nd gear starts without bogging or clutch slipping are easy.

I switched to a single 2.5' system for noise and weight reasons. (and the noise fix-it ticket helped motivate me too)

 

I just talked to Racing beat about this same issue on Friday!!

The tech there said that on a stock N/A both their header system and downpipe system makes the same horsepower. He said that "probably" the only way you would notice a difference is if you had a carbureaton setup, otherwise the stock intake system doesnt make enough power to necessetate headers. Now he did say the header is much louder and many people like this. But for those who arent radically modding their vehicles and want to keep the noise down, the downpipe will do the job.

 

What muffler you running off that single Jimmy, I used to run true duals and they're weren't that loud, it's all in the muffing.


btw, the header I used has consistently shaved .2 sec off my 30-60mph run in 2nd gear, not to mention more low end around town driving that was missing before.

 

My single consists of a moroso spiral flow 2.5" where the cat was, and a ebay special hks dragon ripoff. Right now the heat shielding resonation is louder than my exhaust. (shoulda pulled all of it rather than worring about passenger floor temps)

I never ran the single on the ported motor. It has added backpressure, it's far quieter, and makes the car run a little smoother in the very bottom end. (like under 1K) Top end still screams like a banshee so I don't think it cost me any power. (not noticable if it did)

I had mentioned in another thread that the moroso unit choked the motor, but that has been chalked up to bad gas at this point.

 

Sorry for the dumb question, but what are True Duals that you guys keep talking about???

 

quick question...currently I have a corksport single outlet catback and nothing else, except for a leaking gasket;-) I have the rb presilencer not installed and waiting for the rb streetable header. Will this be hideously loud? Right now I set off car alarms on a regular basis. I think my cats are a little leaky too, so that could be why, I just don't think I could handle the car being tooooo much louder. does anyone have a similar setup. I have large porting and many other mods...probably more "motor" mods than the average NA. What kind of power should I see with the complete exhaust in addition to the porting etc...? I ran a search but found nothing concrete, if anyone has some good numbers please share. Thanks.

 

True Duals - Basically you replace the exhaust manifold (square thingy with heat fins that connects both rotors) with dual output pipes (1 per rotor)

On loudness, a good amount of muffling is done by the exhaust manifold & catalytic converter. Using an aftermarket cat & downpipe (replaces pre-cat) the exhaust volume level is acceptible for me.

If I were to add headers, then I'd add a good pre-silencer to keep the volume acceptible.

I have friends with straight pipes, and it's stupidly loud.