exhaust size 2.3/4 or 3" ??

[plumberlux]

hey guys, i got my self a new 2012 single cab lux 4wd 6 weeks ago and i have put all the goods on hir e.g exhaust, snorkle, lift, and muddies, i have been talking to a friend who ownes a midas shop and he told me i got the wrong exhause on it. I got the beausesert 2.3/4 straight through system. he seams to think i should have got a 3" system with a muffler that will have back pressure, as the bigger systems and over spool the turbo ???

what are your thoughts ????

the truck is a dream to drive all tho it uses a bit of fuel. (used as a work truck with a load in the back)

[VMN]

Is it auto or manual?

The beau exhaust is a very good system and with all due respect to your mate, they have been making exhausts for diesel engines for years so they really know their stuff. Personally, I'd run a muffler which they could supply for you. This would be particularly worth doing if you have an auto to get a bit of back pressure. For a manual, the straight through is probably OK.

The reason why so many shops go straight to a 3" system is that unlike BeauExhausts they have not spent the $ to tool to mandrel bend 2.75" pipe which they believe is better suited for the small 4 cylinder diesel in our trucks.

[plumberlux]

hey mate, yeah its auto sorry. a coulpe of my mates have got beays exhausts on there trucks and love them. really good work.

thanks heeps mate

[Rlux45]

Rob bliss said to me go a 3 inch dump, engine and flex pipe then reduce it to 2.5 inch for more back pressure so you get better acceleration, thats just what I got told and that's best for a manual as well
Cheers Ryan

[Hazeyboy94]

I've just kept the standard 2.5" mandrel system & changed the cat to a freeflow torpedo muffler & the rear muffler to a freeflow Flowmaster muffler. A slight rumble out the back & a noticeable difference in the low & mid range.

2.5" is plenty for a 3.0l diesel turbo. No need for any bigger pipe size.

I've just had a original tuner box (chip) fitted & got it dyno tuned and it's making 115.8kw (157hp) & 712.5Nm at the wheels. Enough grunt for me on my Hilux.

Cheers.

[highoctane]

712nm at the wheels? thats more then a 200 series twin turbo cruiser?

[srluxy]

Torque is always higher at the wheels because of the gearing in the drive line. If you measured a cruiser at the wheels it would be much higher

[highoctane]

Are you sure thats not the fly wheel nm? You lose about 30% from fly wheel to rear wheel

[highoctane]

Are you sure thats not the fly wheel nm? You lose about 30% from fly wheel to rear wheel

[srluxy]

You loose hp through the drive line but gain torque from the gearing. Torque and hp are not the same thing

[Hazeyboy94]

It's at the wheels. I'll see how i can post the dyno sheet somehow. I'll try take a pic & put it on my profile pic's in the next few days.

[trigg]

Isnt the standard size on a new hilux 2.5 or 2.75? If you just change the muffler to high flow is there any other restrictions? I have a 2012 TD SR5 and its auto

[Hazeyboy94]

Isnt the standard size on a new hilux 2.5 or 2.75? If you just change the muffler to high flow is there any other restrictions? I have a 2012 TD SR5 and its auto

Yeah the standard size on my 2011 is 2.5". I just changed the rear muffler to a freeflow muffler and took off the cat converter & replaced it with a 18" long freeflow torpedo muffler. The cat will be the biggest restriction.

If i remember right, Aussie law says you can't take off your cat? Here in NZ we don't have that law.

I also just changed out the standard air filter and put in a K&N one. Just basic mods with the mufflers and air filter to help it breath better and have a little bit more power.

[VMN]

If i remember right, Aussie law says you can't take off your cat? Here in NZ we don't have that law.

Yes, but the beau exhausts system includes a high flow cat.

[07luxyTD]

I threw 3" system under mine 4 weeks ago mandrel bent turbo back with stright through muffler. Notice a fair gain from bout 1800 rpm - 2200 rpm then the standard. i Have 2007 manual diesel cant complain

[Hazeyboy94]

I threw 3" system under mine 4 weeks ago mandrel bent turbo back with stright through muffler. Notice a fair gain from bout 1800 rpm - 2200 rpm then the standard. i Have 2007 manual diesel cant complain

Yeah, that's about the same rpm range i noticed my gains after just changing out the rear muffler & cat using the standard 2.5" exhaust. Definitely get a fair bit of restriction with the standard cat & rear muffler.

[lil]

http://www.thumpertalk.com/topic/571594 ... -the-myth/

[07luxyTD]

http://www.thumpertalk.com/topic/571594-exhaust-backpressure-the-myth/

Very interesting and worth reading

[mbxrc]

I put a 2.75" BeauExhausts on my 2008 D4D man, good note smooth power

[whitesr]

I have the 3 inch sterling exhaust with high flow cat, hot dog type resonator with straight through muffler, the dump pump is 2 3/4 inch, im impressed with the low down torque it gave me. pretty quiet but lots of turbo spool noise.

JIM