How do you guys do the piping? I have OBX headers and I want to run it like this... header > 3" electric cut out > HFC > 3" exhaust but my question is how do you make the 3" and the 2.5" from the headers bolt up? I haven't been able to find a 2.5" in 3" out cutout or anything like that. Could someone give me an idea as to how to run this setup?

 

Sounds fun cant wait to see and hear final product.

 

Well you could always just get a 3 inch pipe welded to the 2.5 collector. Problem solved.

 

Sorry to sound like a complete idiot, but how would that work since the sizes are different?

 

Cut the 2.5" off the Headers and weld a 3"....just like he said.

 

its been done everywhere. You can take the 3 inch pipe slide it over the 2.5 and weld the gap up or cut off the collector and weld a 3 inch in. There are options.

 

Got it, thanks for all the input guys. I've decided to do a 2.5" electric cutout and maybe change to a 3" exhaust later on down the road. Local shop wants 200 to install the cutout, weld the flanges, move the cat and resonator back and run the wiring. Is that decent?

 

bump

 

Where did you guys all go?? Just wanna know if 200 is reasonable to have a shop install it or not.

 

No, I had mine welded in for $40.

 

I do all my own welding so i have no idea what i shop will charge you.

 

$40 for what, welding on a muffler...

$200 is resonable if they are using their piping and such, I had my 3" done for $250

 

Sorry Drunkie, maybe I didn't explain right. They want $200 to just install the electric cutout and move the cat and resonator back and get the wiring for the cutout into the cabin.

A 3" exhaust would cost me alot more than that around here. I don't know why, but shops around here are expensive.

 

only time I used 3.0" was on turbo application, complete turbo back.

3" to 2.5" reducer: http://www.amazon.com/gp/product/B001804SEA

 

I think muffler shops charge like $60-75 an hour depending on the shop. I got ripped for $150 for them to weld 2 flanges and a 12 inch long pipe with a bend to join my down pipe from the turbo to the rest of the exhaust. I think $200 sounds about right for what they have to do.

 

Putting a 3" exhaust on an N/A Maxima will add weight and reduce horsepower.

 

How about reading up before posting? They have proven there are gains to be made with a 3" exhaust. Jay_pee has one as well as other mods and runs high 12s ALL N/A.

And I'm sure it's faster than your turdbo 4th gen

 

I'm not familiar with his car, but if he is running 12s he must be making enough horsepower to justify an exhaust that size. Thanks for setting me straight on that one. Now as far as being faster than me, well thats even more unfounded than my claim. Either way my advice is correct for the car in question. Now let me explain why it will work for his car and not for yours.
I have done my reading, not to mention testing and fabrication. I am running a 3" exhaust, but only because I am in the 400hp range and moving a huge volume of air. In N/A applications your exhaust makes best power by maintaining a negative pressure wave in the exhaust system which draws the spent gasses from the combustion chamber as each valve opens. For this to happen, moderate exhaust velocity must be maintained. A 3" system would have such low exhaust velocity that no scavenging could take place. Not to mention the added weight.

 

Your not bringing proof to the table...just what you say.

On the org here are SEVERAL dyno's on different cars, showing gains on the low, mid, high.
Stock, lightly modded, and heavy modded....all power gains. Dyno's are readily available when you search

 

I've experienced the opposite in cars I've actually done exhausts for. Top end was improved by going 2.5" with some compromise at low and mid rpms. I would never push it to 3" on an N/A car. That is also the reason why manufacturers of performance exhaust dont make them that way. What are these dynos in comparison to?

 

too many variables, if you've 'done' exhausts.

Alot of performance companies make 3" version of exhausts. We had prototyped GReddy TiC 3" models on several NA cars, with heavy breathing mods, which eventually were brought to market.
SR20VE powered Sentras need 3" to breathe correctly. K20A2 powered Hondas need 3" exhaust to breathe correctly, esp with heavy mods.

 

2.5" vs 3" exhaust.

I'm not searching, I've explained this time and time again and have converted how many people from saying "omg you can't do 3" exhaust" to "HOLY CRAP look it the gains you got across the entire rev band"

I'm not explaining this **** anymore cause I'm tried of thickheaded people not wanting to get rid of myth's....thats all you go on....myths

 

http://forums.maxima.org/6911918-post8.html

THIS IS THE LAST TIME I EVER EXPLAIN THIS

 

lofl simmer down dude

 

i say just keep the electric cutout (which 200 is a pretty reasonable price) and dont waste more money getting 3 inch later cuz its the same thing. you running the version 2 obx? I'm gonna get these soon. i was thinking about doing the 3 inch exhaust myself. it will cost around 175 here

 

3" ftmfw!! Im pricing a custom setup right now

 

UPDATE: Decided that in the Spring, I'm going to do a 3" exhaust. I'd like to do OBX Headers > Straight pipe to an 18" Magnaflow > Magnaflow Muffler.

I don't really want it any louder than my current setup, but is 18" enough to keep the volume down? Any recommendations on which Magnaflow muffler to use? Here is a sound clip of the car now for reference...



and one under load...

 

my Magnaflow is extremely deep, deep enough to give good sound at idle and acceleration but not loud. i'll check what # it is

 

This is the resonator that I have on my car now...

http://www.hottexhaust.com/detail.asp?PRODUCT_ID=10416

I cannot find a 3" MagnaFlow resonator. The closest thing I found was a muffler in the same shape...

http://www.magnaflow.com/02product/s...e=main&id=8251

Only thing is that the resonator is 4" round body and the muffler is 7" round body. Would that even fit under the car??

 

^ thats what i have, Magnaflow XL

 

this ones a bit better

 

Got the 3" done with an electric cutout. Holy **** is that thing loud with the cutout open!!!

Question though, how did you guys get the 3" pipe over the rear suspension?? It barely fits and it has no room to move. So it either hits when I go over bumps on the top of the underside of the car and it also sits on that control arm (is that what it is in the back??) and buzzes like crazy. Any fixes? Would header wrap on the exhaust piping there help?

 

remove r/r wheel, make brackets to bolt/ weld from inner frame/ body to exhaust piping to hold stable, spray paint bracket w/ high temp exhaust paint.

 

Won't bolting it up to the frame cause rattling in the car still?

Anyone happen to have pictures of the rear section? (haha )

 

You need to talk to KRRZ350 about this issue. He installed my Cattman 3" and and figured out a way to make it so the exhaust never hit. It was rock solid and never hit. PM him and ask him exactly what he did. Pretty sure we put a hanger in that area, but he can explain in more detail.

 

Wondering the same.. i'm getting mine done this week and would like to know where to get a hanger before my shop begins so I make sure they know. It would save both of us headaches.. awaiting pics?...

 

Pictures anyone? My buddy said that like a piece of old tire would fix the rattle. Ghetto, but it will withstand the heat. If that's what I gotta do, that's what I'll do.

 

Alot of times what's thought to be "ghetto" Just because you don't blow your money and does the EXACT same effect as some shop woulda made and charged for can be "smart".. Difference between Ghetto and smart... Fine line between... Also I'm having my shop make me a 3" as I described but the muffler I wanna transfer over has a 2.5" inlet, anyone think i'd be losing power because of this??

 

thats not really ghetto, as long as it does the job and nobody can see it, theres nothing wrong with using a piece of tire

my stock exhaust was ghetto, i got my Magnaflow put on in spring of 09 so my stock exhaust lasted 17 years in Canadian year-round weather. the hanger was bent to ****, and a 3/4 chunk of the bottom was rusted and broken off dangling. no noise from it though, dead silent but it looked horrible.