desiboy

Hey everyone. I dont own a Maxima but I became in need of a variable capacity but HIGH FLOW muffler. I didnt know Maxima's had such things i didnt even know if variable capacity mufflers existed.. but when I did a search I saw they came stock on these cars.. my question is does anyone know the flow specs on these mufflers? and inlet and outlet sizes?

my car is just asking for a better muffler than I have.. it only flows 400 CFM (Dynomax Superturbo) but the thing is.. that 400 CFM is a perfect flow volume when the car is between 3500 - 4000 rpms.. but after that 400 CFM becomes a restriction.. I need it to open up about a 100 or 150 CFM for each 1000 rpm increase.. so 400 at 4000, 550 at 5000 and so forth..

oh and the reason i dont just grab a 1000 CFM muffler from magnaflow is because i would just lose all the low end torque the car has..

any comments are welcome.

CBass69187

iTrader: (4)

I don't know all the flow specs so I cant help you there. What set up are you running on your j-body? Unless you are running forced induction, I have a hard time believing you are flowing more than a 5th gen.

desiboy

These are my current engine mods..

Upper Engine Mount Insert
Lower Engine Mount /w Upgraded Bushings
NoyzBoyz Cat-Back 2.5" Dynomax Exhaust w/ Magnaflow Resonator
Induction Dynamics Cold Air Intake
Stage V Port & Polish w/ 5 Angle Valve job
RSM 59mm Throttle Body
Nology Powercores
Ported Exhaust Manifold
2.5" downpipe
2.5" High Flow Catalytic
Exhaust Cam: 200 DEGREES @.050 WITH .375 LIFT (coming soon)
Intake Cam: 200 DEGREES@.050 WITH .360 LIFT (coming soon)

..the cams are sitting here waiting to be installed..

my exhaust is 2.5" straight from the manifold.. I know the muffler is a restriction over 400 CFM.. if the variable capacity muffler can flow more.. than i think ill grab it.. i can get a hold of one for 130 CDN..

victor

iTrader: (1)

what kind of car is a j-body?? sorry, i'm so stupid.

CBass69187

iTrader: (4)

If you can get ahold of one for only that much I think it would be a good deal, even if it doesnt work, sell it on here or ebay.

pezking4

Cavaliars and Sunfires = J Body
Camaros and Firebirds = F Body
Corvette = Y Body

victor

iTrader: (1)

oh, i see.

Jer

iTrader: (2)

o/t of this forum but you forgot :
grand prix/regal = w-body

those are the most important of all

Norm Peterson

This original G-body owner (RWD Malibu/Monte Carlo/Grand Prix/Regal) begs to disagree a bit

desiboy - Back on topic, just how much more than 400 cfm are you expecting? Has this car received an engine swap?

And since a flow rating has to be associated with a pressure drop across the muffler in order to mean anything, what are you using here? And that's only approximate anyway, since exhaust flow is pulsating in nature rather than steady flow. Even aft of the converter.

Memory suggests that mufflers are rated at something like 1.0 psi, but they will flow more than their rated flow at the expense of increased backpressure. Increasing the flow from 400 to, say, 500 cfm would increase the back pressure to about 1.5 psi, for about a 3% power penalty at that rpm. At lower rpm's that are still above wherever you get 400 cfm of exhaust flow the power loss will be less. But this still comes back to knowing what the exhaust flow really is (or perhaps being able to estimate it from displacement, rpm, exhaust gas temperature, etc.).

Norm

Kojiro_FtT

Forget all that mumbo-jumbo. If you are still NA, then the Max muffler is plenty for you. Go ahead and get it, and make sure to tell all your friends where you shop when you need advanced performance parts - Maxima!

(lol, that would be funny to start a new performance trend, every 4-cyl will be wanting to do a "muffler swap" for a Max muffler. But then they'd start to be stolen, like the HIDs )

Jer

iTrader: (2)

True thing with that G-body thing woops..

Hey imagine waking up to find some dude lying under your car and sawing away at your exhaust!

Norm Peterson

Sorry if my hardware-oriented engineering sounded confusing, but my position is that if you're going to 'upgrade' you need to know at least a little of the tech that's behind it so that you can make intelligent decisions. And if the numbers showed that the HP gains were only going to be, say, 2 or 3, I'd start rethinking just how much I'd willingly spend to get it.

Quote:

Go ahead and get it, and make sure to tell all your friends where you shop when you need advanced performance parts - Maxima!

(lol, that would be funny to start a new performance trend, every 4-cyl will be wanting to do a "muffler swap" for a Max muffler. But then they'd start to be stolen, like the HIDs )

So if we installed lowering springs, could we then claim them as anti-vandalism techniques to get a break on the comprehensive portion of our insurance?

Norm

Jer

iTrader: (2)

That would be sweet! I'm still a fan of that flame-thrower security system they used overseas though... there's nothing like making a human steak out of the guy that just tried to part out your car

Kojiro_FtT

I agree Norm. I just have a feeling this J-body owner isn't going to be able to provide/find the numbers you are asking for him to look at to make his decision. Maybe I'm wrong.