Who said you can't run 3"

3" Borla cat-back without headders.

0-70 on the backroads. Don't forget I am not running 100% due to me needing wires and plugs causing misfires.

[ame=http://www.youtube.com/watch?v=nUpzbbcPXS4]YouTube- Exhaust acceleration clip.[/ame]

Idle clip and showing the hangers.

http://www.youtube.com/my_videos_edit

Why?? are you planning turbo down the road? Cause you are loseing power by running this setup. Does sound good though

Nope staying n/a. You might of seen my rides thread on sli. I am going to port and polish the heads, get cams grinded and new internals. I am more of a n/a guy. And I really do not think that I am loosing power (besides throwing a code for misfire before the exhaust). I think that it is breathing a lot better. I keep hearing that I am "loosing power", but where are the facts? I understand that the car is breathing better, but do not feel a bad difference. Oh well the backflow and vac test will tell all.

yea your gonna do a back test and stuff ? cool keep us posted on if its true. Your right id say its more of a rumor with not much fact behind it but it does seem to make a bit of sense with 3 inch hurting power on n/a. Plus think of all the engineering that goes into name brand exhausts like HKS and APEXi. All there N/A setups are around 2.25-2.5in on there fully built race motor hondas and such. So there is prolly some fact behind it. But hey if you can prove it wrong that be awesome.

Digging this up from the grave. Lol

 

Did you ever back pressure test the 3" exhaust? I just got a brand new 3" 02 wrx cat back for $100 shipped to my door that I will be getting fitted on my 97 LGT soon. If 3" is proven to hurt performance, ill get them to make a 2.25" mid pipe and it will be all good, but if 3" is fine, why spend the money on a smaller mid pipe?

 

And also, it may only be 2.5" on their fully built race n/a hondas, but their hondas are a lot less displacement then our 2.5L. A year or so ago (06 I believe) Modified mag dyno tested and proved that a 3" cat back is best for a 95-99 240sx with stock ka24de (2.4L N/A inline 4) in terms of power and torque. I also had a 95 240sx with a 3" cat back and the car loved it, A-LOT! Lol

 

I think for smaller displacement 4-cylinder motors, 2.25" or 2.5" is best, but it seems to me that 3" might be just as good if not better for a bigger displacement 4-cylinder (i.e. Our 2.5L) and that makes sense when you think about it. A Honda 1.8L B18 or 2.0L K20 would use 2.25" or 2.5" but the bigger Nissan 2.4L KA24 and Subaru 2.5L EJ25d could use 3"

 

After all, it is flowing more air, with more displacement...

 

I would love 2 see the back pressure test or some proof if 3" is bad on our cars.

 

Thoughts?

 

-Ben

Have since installed UEL headers, Magnacor 8.5mm wires, NGK v-power plugs, and Msd ignition. I wanted to wait to fix my misfire and the weather to get nicer to get in there for the backflow. Everything is now fixed. I would say go for it! I have had no complaints about acceleration with the oversized exhaust. I think my neighbors hate me in the morning though!!!

Here is a new clip before the MSD!

 

[ame=http://www.youtube.com/watch?v=nFoitoMRMak&feature=channel]YouTube- Boxer Rumble[/ame]

 

Need speakers that can pick up the deep tone to hear it all!

Ha ha nice! I just love the look and sound of a nice 3" exhaust on a "big block" 4-cylinder in the morning... ha ha

 

I'm thinking go for it as well. With the 3" cat back and a custom 2.5" cat delete pipe and o2 sensor cel fix adaptors, it HAS TO flow better and make more power and torque than the stock 1.8"-ish piping with 2 in line cats and 2 resonators!!

 

 

I'm down to join the 3" n/a club. . Lol

 

-Ben

get dyno'd and you'll realize it isnt as much of a gain as you think.

 

2.25" exhaust is the best for our engines without internals done. and 2.5" is best for internals done.

 

here is a dyno of my car vs my friends ant's.

 

BOTH legacy GT 2.5s

 

mines a wagon his is a sedan.

 

both have borla headers and headerback exhaust

 

Mine: borla headers, stromung highflow cat, stromung catback all 2.25"

Ants: borla headers, track pipe, custom 2.5" catback w/ straight muffler

 

both have CAI's and MSD ignitions, and grounding mods.

 

Both 5 speeds.

 

He has intake manifold spacers also! so 1 mod up on me.

 

I still made more HP to wheels than he did with same mods, and I had a cat and he had a intake mani spacer too.

 

-B

 

http://i49.tinypic.com/snpixi.jpg

I can't read the numbers on the chart on my black berry, its 2 small. :/ How much more power and torque did you make than your buddy?

I can't read the numbers on the chart on my black berry, its 2 small. :/ How much more power and torque did you make than your buddy?

 

12hp 20trq with a cat. and less mods

 

-B

I see... Hmm. Interesting.

Did they have same size wheels and tires, and similar mileage?

You cannot not compare two cars togther to get results. The only way to make this comparison is to have the same car dynoed with 2.5 in and 2.25 in. Otherwise there could be more to the results.

That's what I was getting at. Lol tire size, rim size, rim weight, oil type and weight, ammount of oil, mileage, motor condition, fuel type, all of it and more can make a difference. For instance, people run their sohc hondas a quart low on oil and pick up a 1/10 of a second in the 1/8th mile. (I don't reccomend it, I'm just saying) Something so small can change a lot. So I agree, dyno the same car with both exhaust set ups to get a true comparison.