2 or 2 1/4 inch exhaust

[rocknferoza]

Getting the exhaust done on the feroza and wanna know what u guys think.
Should I get a 2 inch or go for a 2 1/4 inch I'm getting either lukey or hurricane headers, flex joint and a hi flow cat.
Would I lose down low torque with the 2 1/4 as a mate of mine runs that size and he said his pulls better on hills in 5th gear but other guys have said they lost down low torque with that size.
This is going on a 1.6 litre

Thanx

[Big Red Toy]

go the larger exhaust, u won't loose power as that is just an urban myth

[up2nogood]

From the point of view of a dopey bugger who owned an exhaust shp for 4 years.......

Fit a straight through 2". That's heaps. Use a muffler sized resonator in the middle (not those pissy little ovals or hot dogs) and try to squeeze one of the smaller ovals at the back.

2 and a quarter is more for commo and falcon sixes.

That way you'll get good flow and not scare too many birds as you drive by. Recomend you also consider a good set of extractors as well.

[murcod]

2" works well on my Feroza, and get the Hurricanes while you're at it.
Have a read of this too http://www.magnaflow.com/07techtips/faq/question10.htm

You'll be hard pushed to fit a res and a muffler- I tried but there just isn't enough room.

[rocknferoza]

:D 2" works well on my Feroza, and get the Hurricanes while you're at it.
Have a read of this too http://www.magnaflow.com/07techtips/faq/question10.htm

You'll be hard pushed to fit a res and a muffler- I tried but there just isn't enough room.

Exhaust should be getting done tomorrow if all goes well. The guy thats doing it does a realy good job Probibly get lukey headers most likey but will ring him tomorrow morning and discuse about the exhaust size.

Hey Dave I asked ShaneC about his exhaust because hes got a 2 1/4 inch and he said it pulls much better in 5th gear on hills with his exhaust and thats with genie extractors.

[diesel028]

go the 2 1/4

[SiKiD_01]

i can't remember what the original size of my exhaust was, but i went 2" straight through. i had extractors made up, and a hi flo cat, with a cheap redback mega flo muffler (small).

i noticed that i lost low down torque, but my 1.6 (vitara) would rev a little more higher, and the power/torque was higher up in the revs.
normal operating revs is from 2400ish to 3500ish. it was lower when i first got the vitara.

some people say that too big of a exhaust has negative effects. (backpressure or something) just think of straws...... get one from mcdonalds (for milk shakes. is bigger diameter), and get one from the cranky old asian take away on the corner, if they even have straws for you (usually smaller dia), and try to blow through both. obviously the bigger straw will move a lot more air. anyway, the point i think i'm making is that if the dia is too big, it will work against you.

i also have a nissan X-Trail, 2.5L 4 cylinder. i put a 2.5" exhaust straight through from the engine, and a small lukey muffler at the very end (also has other mods to compliment exhaust). this is good and bad, it now hits the redline limiter a lot, (no thanks to short gearing) but is way more responsive and accelerates harder and quiker, and its heaps noisy!

anyway, if you like to rev higher and harder, go bigger, but the 2" is good for a 1.6 with extractors/headers, good muffler(s) and hi flo cat. but then again, its not really worth it if your air intake has a bad set up. cars are like us, they need to breathe good and more fresh air is best.

should be good for $1 worth
steve

EDIT: sorry, i didnt "borrow" the straw thing from the link above, i wrote this before i looked at it. i read up on it a while back when i was getting my exhaust done. sorry for stating the obvious.

[rocknferoza]

Already got a good airfilter fitted. Got a group N unifilter airfilter

[Beastmavster]

Went a 2" into 2 1/4" system on the vitara and it WAS too big. Needed to be a 2" system right through.

Had 2 1/2" on my Datto.... much bigger engine. 2 1/4" is overkill for the size of engine and the intended use. A bigger zorst will flow more at high RPM but you do need some level of backpressure to enable scavanging at low RPM.

[Daisy]

urban myth my ass...

2 inch will give better torque down low which is what a feroza needs.

2 and 1/4 will give more top end which is a bit more power on the highway for overtaking etc.

Just comes down to what you want to use your car for?

TOM

[murcod]

Even with 2" I noticed a loss of torque at lower revs- would hate to think what 2 1/4" would be like! You need to advance your timing as far as you can to compensate.

James, the Lukey extractors are 4-1 which will also give more of a power shift into the higher revs (and less torque down low.) Hurricanes are 4-2-1 which are better for low rev torque. Mine will still rev out a lot better than standard and has heaps of pick up in the higher gears once you're past 3000RPM. I think Dangerous Dave has got the Lukeys on his- try PMing him to see what they're like.

You should be paying around $100 less for the Lukeys too- I was quoted $160 for them and paid $275 for the Hurricanes.

Could be worth gettting a new Oxy sensor while you're at it. Most likely the old one will be seized into the old manifold and the thread will be stuffed once you manage to remove it. Do a search in the Daihatsu forum and you'll find the part number for an NGK replacement, around $80 retail (comes with a longer lead to reach the extractors.)

[V8Patrol]

urban myth my ass...

2 inch will give better torque down low which is what a feroza needs.

2 and 1/4 will give more top end which is a bit more power on the highway for overtaking etc.

Just comes down to what you want to use your car for?

TOM

& I second this post 100%......

its a 1.6 for gawds sake !!!, next thing will be some dill wanting to run a 3" on a LJ50 zuki with the std 850cc two stroke motor


Kingy

[bogged]

4inch straight thru, with an 8inch dumper...

[zbuild]

I agree with GQ and V8 Patrol. . ..

Too big an exhaust on a small capacity engine will kill torque

The "BIGGER is better" theory only works on Turbo'd engines, and then only to a certain extent. . . .I read somewhere. . I think it was in Corky Bells book on turbo'ing that a good mandrel bent 3" system is good for up to 450hp

[dow50r]

Gday
A nice trick is to put extracters followed by 2.5 inch to the first resonator b4 the diff, and after that, 2.25 inch to a rear muffler, and a 2 inch outlet...not sexy to look at,but quite functional, as the hot stuff can get through with less restriction, and as it cools, it slows down, but with smaller pipe, the flow stays thesame speed. with the 2 inch outlet, noise is reduced aswell...have it pointing to the ground at 45 degrees too.
Had this with good results on the old datto rally car
Andrew

[bogged]

Had this with good results on the old datto rally car

I miss my old 510 :(