2.5" exhaust??

[mac_stang]

Hey everyone, im considering cutting my exhaust just after the 1st hanger, and going 2.5" pipe only(no muffler or bottle) and coming out just before the rear swing arm mount...any one done it?(sound level?) my exhaust is shot and i have been planning a 2.5" up grade anyway, and i have heard some l300 with side exhaust and they sure sound "healthy"! Any thoughts would be greatly appreciated.

Brad.

[Tojo]

This is a good thread:

http://www.delica.ca/forum/another-exha ... -7985.html

[1994delicaman]

I straight pipde my L400, I just cut out the original muffler and put in a piece of pipe for the replacement. As for the noise level it is not much of a difference on the inside but it does have a mean growl when you roll the windows down and really step on the gas pedal.

[RichD]

2-1/4" is the max that fits correctly to the adapter. You should use at least a straight through resonator to limit noise.

On my L400 I just had to remove the exhaust that the previous owner installed because it was not legal - it was too short, loud and positioned such that exhaust could enter the vehicle through a window. It was a bad idea custom jobby and while it was fun to hear it roar the first few times, it quickly became annoying on the highway.

On my L300 I had a custom made stainless exhaust and mandrel bent 2-1/4" pipe. It sounds delightful and the performance improvement was immediately tangible. Fuel efficiency up as well.

A lot of people are using the Magnaflows here. I don't like them so I got something higher end. Laurentiu expressed an interest in the muffler so we're bringing some in as an option for his exhaust kits. They can be made in 4" round or a triangular shape; the latter can be used to improve clearance in some vehicles. On the L300 there is plenty of room for the round one to clear so I went with that.

[mac_stang]

thanks rich, but i would be cutting the pipe imediately after the first hanger and eliminating that flange(exhaust gasket) and its not hard to flare a pipe for an increase to 2.5". I cant believe it would be that unbearable noise wise considering most if not all diesel noise is from the engine itself and that is definately the case in my l400. I had a 1980 chevy pick up(4x4 of cousrse) I had a 3v53 Detroit deisel in it, it sounded like a transit bus but the 5" exhaust wasnt the cause...it was all up front!

Thanks for the advice though!

Brad.

[jessef]

as a reference at idle, the sound is similar
at 1/2 to full throttle a straight pipe is almost twice as loud as one with a muffler

The shorter the pipe, the louder it is

I drove a few blocks without any pipe and it sounded like a WW2 tank literally

[BV1]

I did a 2.5" exhaust recently, used a magnaflow muffler (not straight through), exited at the rear. Changed engine resonance from 2k RPM to 2500. Hard to say is peak torque is up or down at 2k, I suspect the same, but torque from 2300-3000RPM is definetly up with a sweet spot at 2500. Its easy to see on the EGT guage too, temps down all around by around 100F at similar loads, except at 2500 where its down ~125-150F at similar loads.

Good mod,

Steve

[mac_stang]

She's done, side dump just before the rear swing arm mount. Sounds like a Sherman tank(a little one anyway). Still the quietest diesel I've ever had. The turbo sings beautifully, and the sound disappears the second the drivers side window goes up. 2.5" from just before the first hanger. I like it, and noticed an increase in power right away(did the coquihalla the day I did the exhaust)


Brad.

[mac_stang]

A couple weeks in and the most notable change has been highway driving. She cruises at 120kms like it did at 90kph, there is a huge decrease in back pressure which is great for hi speed and I no longer have to tip into the throttle to cruise DOWN the Coq.


Brad.

[CREGAN]

A couple weeks in and the most notable change has been highway driving. She cruises at 120kms like it did at 90kph, there is a huge decrease in back pressure which is great for hi speed and I no longer have to tip into the throttle to cruise DOWN the Coq.


Brad.

I recently just went to 2.5 as well and I totally agree with you. It cruises very nicely at 120, and sometimes when I am not paying attention it even purrs nicely at higher speeds. Before it would have really felt like it was trying hard to stay at that speed. Like they say though that every action has a reaction, my fuel economy has gone the way of the crapper. I am afraid to log my last month or so on Fuelly because I bet I am consistently in the 15's now. I probably get about 475 to 500km to the tank now. Not great but the trade off was worth it.... I think

Craig

[nxski]

A couple weeks in and the most notable change has been highway driving. She cruises at 120kms like it did at 90kph, there is a huge decrease in back pressure which is great for hi speed and I no longer have to tip into the throttle to cruise DOWN the Coq.


Brad.

I recently just went to 2.5 as well and I totally agree with you. It cruises very nicely at 120, and sometimes when I am not paying attention it even purrs nicely at higher speeds. Before it would have really felt like it was trying hard to stay at that speed. Like they say though that every action has a reaction, my fuel economy has gone the way of the crapper. I am afraid to log my last month or so on Fuelly because I bet I am consistently in the 15's now. I probably get about 475 to 500km to the tank now. Not great but the trade off was worth it.... I think
Craig

Strange, my fuel economy and air care ratings got better with the larger exhaust. Maybe you're just taking advantage of that extra power rather than just driving it the way you were before and this is causing worse economy? Or the winter diesel?

[Paule]

Mac_stang, where did you guys get the work done? This is on my to do list very soon...

Cheers

p

[CREGAN]

Strange, my fuel economy and air care ratings got better with the larger exhaust. Maybe you're just taking advantage of that extra power rather than just driving it the way you were before and this is causing worse economy? Or the winter diesel?

Yeah, I think my foot strangely got heavier. I also had it tuned at Coombs to rid the black smoke issue, but without a complete IP rebuild (lack of time) they did the best they could to tune it and not loose alot of the HP. It is kind of a trade off- I still have black smoke when accelerating, but I have lots of power.

Craig

[nxski]

I'm guessing this is illegal but other than legality, is there any problem just rwmovinf the exhaust entirely? "I'm sorry officer, it fell off and I'm just on my way to the muffler shop"

[mac_stang]

There is nothing illegal about removing a muffler. But there is a sound limit in dbs. If your vehicle comes equipped with a catalytic converter-it cannot be removed, because it performs an emissions. Control function. I've had numerous vehicles that are considerably louder than my stair piped Deli.

Brad.