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HybridZ

muffler choice?


lilesrebel

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it dont matter what the muffler is,your NOT gonna see nowhere near 40. especially just changing a muffler instead of full exhaust. i highly doubt you will see a change of more than 10-15whp witha full exhaust on these cars....i could see it coming out of a built v8 tho.

 

i am running a full 2.5 inch exhaust from a 6 into 1 header from AZC to a flowmaster for starters. i might change the muffler later if i get tired of the flowmaster.

 

but i would think that i would gain 15-30hp considering the stock exhaust is so restrictive, and the manifold has the crappy emmission control setup

 

the car will be painted this month and the motor will be put back in shortly after then i will run my exhaust.

 

the car has been put through a rough ground up restoration and it is all comming together again.

 

I will post some pictures up in this thread as soon as i can.

 

thanks for all the help.

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but i would think that i would gain 15-30hp considering the stock exhaust is so restrictive, and the manifold has the crappy emmission control setup
The stock S30 exhaust systems were just fine for a stock motor and did not significantly reduce power.

 

I'm not sure what crappy emission control setup you're referring to on the S30 exhaust manifolds? From what I've read and experienced myself, the stock exhaust manifolds do a very good job and only become a limiting factor when you begin to modify the head/cam setup.

 

Back to the original question, I have the MSA header (6:1) with their 2.5" exhaust and dynomax muffler. It was a bit loud in a good way with the stock cam and quieted down a lot when I upgraded the cam. At this point now I've had it on the car for about 3 years and quite a few track days and the baffling in the muffler is loose. When it gets warm at idle, it sounds like I have a bad muffler bearing :) Also, the sound from the driver's seat with window down is rather raspy at WOT as the revs go from 3.5k to 6.5k. I can only imagine how it sounds from behind the car.

 

This spring I'll probably replace it with a flowmaster as I really don't want to attract attention with all the racket when driving on the street.

 

Also, when listening to the videos on youtube, keep in mind that the placement of the camcorder makes a big difference in the tone. Notice how much deeper the sound becomes when the camcorder is placed on the ground vs. even a foot or two up in the air. I wouldn't put a lot of stock in the sound from the videos - much better to hear one in person if you can arrange it.

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Does MSA sell just the aluminzed exhaust tubing by itself which would allow me to buy a different muffler? I don't really like the look or sound of the dynomax to much.

The MSA piping still needed tweaking to get it to fit properly. In the end, I would have been better off taking it to a custom muffler shop to build from scratch.

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The MSA piping still needed tweaking to get it to fit properly. In the end, I would have been better off taking it to a custom muffler shop to build from scratch.

 

Thats what I was affraid of. Anybody recommend any exhaust shops in North Houston Spring area.

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I'm not sure what crappy emission control setup you're referring to on the S30 exhaust manifolds? From what I've read and experienced myself, the stock exhaust manifolds do a very good job and only become a limiting factor when you begin to modify the head/cam setup.

 

I dont know if You have or not but if you have seen the exhaust manifold on a 260z it's completely different than a 240z or a 280z manifold. the 240z dosent have the strict emmissions on the car as the 260z had.

 

the shape of the 240z manifold compared to the 260z is similar though.

the 280z had a longer bigger and heavier manifold than the 260 and it flowed better to

 

the hp on a stock 240 comparred to a 260z the 240z is higher.

when the government issued strict emmision control laws in 1974 nissan didnt know how to deal with the problem so they upped the liter size and put the emmissions on a twin su carburated setup resulting in lower horsepower than the 240z which is why the 280z with bosch L-Jetronic fuel injection was born, so the it could have the emmissions control but still good power

 

240z hp: 151

260z hp: 139

1975, 76 280z hp: 149

1977, 78 280z hp: 170

 

to my knowledge this is right but im sure someone on here knows more about it than i do

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I can't cite anything offhand, but you aren't totally right.. all the L28Es had the same power (~170 flywheel HP) all L26s had the same FWHP, and all L24s had the same FWHP (this i believe was the 151.)

 

There is alot of confusing information out there, and the source of confusion is flywheel versus wheel power (your 75-76 280Z figure is WHP for 280Z, the stock WHP for 240Z was something like 121) All this is, of course, USDM and may not be *exactly* right, but its closer than you are. not tryin to be a dick :)

 

The exhaust manifolds are all different.... but none of them restrict or otherwise impede exhaust flow in any appreciable way regarding a stock motor; the only reasons to go with an aftermarket exhaust on a stock motor are:

 

weight savings

sound

you plan on doing more serious modifications later and just want to

 

All of which are perfectly acceptable reasons...

 

 

..but the day an exhaust system nets any L-powered Z-car with a close-to-stock engine a whole 40 horsepower is the day I eat my torquewrench.

 

Period.

 

I could believe bolting a single 1 1/2 inch pipe up to a stocker 240-280 would DECREASE horsepower by about 40... but there simply aren't even 20 horses left to be pulled out of just an exhaust... you would need to have a WILD head and cam combination, high compression pistons, and 44mm triple carbs (or serious aftermarket EFI and a non-factory intake manifold, the factory EFI manifolds are more of a bottleneck than 2" pipes) and STILL be running a stock cast iron exhaust manifold and pipe system to see a gain of 40 horsepower from just doing the exhaust.

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