Much difference between a 2.25 exhaust and a 2.5?

[rwaterman]

I know that a 2.5 system is more free flowing than the 2.25 but is there really much difference when driving between them?

I currently have a magnex which is a 2.5 system but am thinking of changing to a janspeed which is a 2.25.
With the magnex there, to me is a nice increase in torque which feels very free flowing to drive with, would I lose, notice a slight restiction when downsizing to a smaller bore?
I really aint got a clue to be honest, the size difference sounds small but in terms of free flowing design how free flowing is it on a standard car?
Also how would future tuning be affected with a 2.25 over the 2.5 or is there really nothing in it?

Cheers

Rob.

 

[ja.jack]

Contact Ben R. He is about to introduce the ultimate Clio high performance exhaust, so will know all about bore size relative to performance ect.

 

[Peperami]

Arnt magnex and janspeed much of a muchness?

Looked at yozzasport/ btb yet?

 

[rory182]

if you have a cat It probably doesnt matter what diameter it is behind it, will affect the noise more than anything. The cat would be the major restriction I'd think.

mines 3" from the cat back

 

[LegoHead]

Its a pipe.....gains are fook all between best and worse exhausts. Only ever buy one for the sound you get.

But you can make the car slower if you make drastic changes to the bore.

 

[rwaterman]

All I know is ive had 3 magnex systems in 2 years and have had to fork out all times for fitment, I waited months for the "new design" when it finally arrived they had sent me the wrong system but I only found this out after I paid someone again to fit it!! Now I am waiting for another replacement and have requested they pay for fitment as it wasnt my fault they sent the wrong one!!!
To say im fucked right off is an understament!!
Anyway the janspeed gets good reviews on here and the trophy forum but I just dont want it to feel that little bit more restricted, if it does?? I dont know?

 

[rwaterman]

if you have a cat It probably doesnt matter what diameter it is behind it, will affect the noise more than anything. The cat would be the major restriction I'd think.

mines 3" from the cat back

Rory isnt 3" to big what exhaust is that? Im not talking tailpipes, just the size of the system diameter

 

[ja.jack]

In my limmited knowledge a big bore exhaust on a standard motor will lose you torque, there are many variables, so lets wait for the experts/exhaust sellers to enlighten us.

 

[rich[182]]

Contact Ben R. He is about to introduce the ultimate Clio high performance exhaust, so will know all about bore size relative to performance ect.

Is that the one due out last June ?
http://www.angel-works.co.uk/products.php

 

[rory182]

if you have a cat It probably doesnt matter what diameter it is behind it, will affect the noise more than anything. The cat would be the major restriction I'd think.

mines 3" from the cat back

Rory isnt 3" to big what exhaust is that? Im not talking tailpipes, just the size of the system diameter

Blueflame, it's a 3" pipe with 3.5" tail trims.

My low down torque is definitly improved, don't see any power gain from zorst alone though.

 

[Lagerlout]

In my limmited knowledge a big bore exhaust on a standard motor will lose you torque, there are many variables, so lets wait for the experts/exhaust sellers to enlighten us.

Ditto.

Exhaust are actually something of a science rather than being "just a pipe". You need to get just the right bore so on exhaust pulse helps to exhuast the next one. Or something. lol

 

[rwaterman]

Rory isnt 3" to big what exhaust is that? Im not talking tailpipes, just the size of the system diameter

Blueflame, it's a 3" pipe with 3.5" tail trims.

My low down torque is definitly improved, don't see any power gain from zorst alone though.

I see, I thought it only went up to 2.5 with these cars tbh..

 

[rory182]

in turbo cars and 2 strokes the exhaust designs are more critical I think, the manifold is the real important bit surely.

2 stroke zorsts are shaped to create a sound wave which bounces back down the zorst returning un burnt fuel into the engine, clever!

 

[rwaterman]

I always here that the 2.5 size is well suited for the clio..

Say if you measured the 182's power with the 2.5 then changed over to a 2.25 would there be any difference?

 

[LegoHead]

In my limmited knowledge a big bore exhaust on a standard motor will lose you torque, there are many variables, so lets wait for the experts/exhaust sellers to enlighten us.

Ditto.

Exhaust are actually something of a science rather than being "just a pipe". You need to get just the right bore so on exhaust pulse helps to exhuast the next one. Or something. lol

Its a small mod on a clio that doesnt seem to get good gains....may as well strip the paint off the car to lose weight.

 

[ja.jack]

You recognise irony mr rich.

 

[BenR]

maybe i should stop work all together and just concentrate on developments, then hand the results over to someone else?

 

[rwaterman]

BenR whats your thoughts on the original questions?

Ta,

Rob.

 

[BenR]

all depends on application, peak imposed bhp, engine VE curve, ex manifold configuration.

Both will work, but as with anything on a car, it takes time, money and testing to arrive at an optimum solution.

All these exhausts will have diff silencer construction, sizing, placement and rear box split design, so they cant be directly compared.

IMO i think 2.25" is a tad too small as the F4R's like to breathe and any back pressure doesnt sit will with them........infact all modern cars dont really like back pressure at all. Sadly some adages pass on with the times rather than dropping dead.

 

[ja.jack]

Regurgitated gobbledegook. Is the maestro losing his marbles?

 

[BenR]

i never had any, we were too poor and i played with camel dung in the dunes.

 

[ja.jack]

Thought you were the indulged son of a pater who made good in one of our ex colonies?

 

[BenR]

nope, just a dung throwing, sand bathing, genocidal, b*****d leaf eating son of humphy bogart.

 

[f4rt3d]

nope, just a dung throwing, sand bathing, genocidal, b*****d leaf eating son of humphy bogart.

:clown:

 

[ja.jack]

Yep. marbles gone.

 

[len_beach]

I was under the impression that 2.5'' was the optimium although that is only a generalisation. But being a mindless cretin, what would I know.

 

[ja.jack]

What do you know len bit*h?

 

[mini-valver]

Another well backed up and respected flurry of posts by Ja.Jack. Oh wait, no.

From what ive used and heard about in reveiws etc, on a road car you will see little if any difference between any of the major exhaust companies as all use the same principles/design features...

 

[len_beach]

What do you know len bit*h?

I know jack.

 

[ja.jack]

I dont know much mini-valver, but I'm confident in saying I know more than you!

 

[mini-valver]

I dont know much mini-valver, but I'm confident in saying I know more than you!

LOL. Realted to my post in what way? Besides, you use no context so how would you prove this? I don't claim to know much. I know what i need to know which is just lovely

 

[ja.jack]

When you went to Ben's workshop and waxed lyrical about the wonderful machines you saw there was one of them a dildo?

 

[mini-valver]

Dude, you need to get out more! Engine tuning requires dildos to get the most out of them, obvously....

 

[BenR]

lol (and for once that term is being used correctly haha)

maybe you need to come down jack and loosen up, go with the flow...........get groovy man.

 

[ja.jack]

Dont know how to answer that Ben, all I want is my Clio tuned to best effect. No strings attached!!.

 

[BenR]

so dont attach strings.

 

[ja.jack]

Sounds like a serious tuner,nicht. Mark and others must be worried.

 

[Bloooor]

lol at what this thread has become!

 

[ja.jack]

Do you approve mr Blooooooooooooooooooooooooooooooooor?

 

[Peperami]

This is what drugs do kids. Drugs are bad mmkay.

As for the original post, ive got 2.5" pipework.

Think a good free flowing exhaust is more to do with smoothness of design and keeping an even size through the bends/ silencers etc?