Why does my exhaust only pop/bang when the car is cold?

[unfortunately_french]

Hello all. I've recently fitted an rs192 decat stainless system to my 182. It's a good exhaust in terms of not being too noisy at low revs and you can make the car very quiet by being light on the throttle. HOWEVER i like my exhaust to pop/bang yet I can only get it to do it when i've literally just pulled off of my drive when the car is cold and the weather is below 5 degrees C. If you rev the car to about 2.5k-3k rpm and come off the throttle it makes a nice bang, but by the time I get to the top of my estate, 300metres approx, it stops as the car starts to warm up! Anyone else had this or know the cause?

 

[172Ben]

its normal iirc

Have a search

 

[unfortunately_french]

Searched rs192, searched pop, searched bang. Found NOTHING about what i'm talking about.

 

[.Tyler]

Same here mate, same exhaust too.

Think it's to do with it using a bit more fuel while warming up?

 

[unfortunately_french]

Same here mate, same exhaust too.

Think it's to do with it using a bit more fuel while warming up?

Right, do you have to go really slow to make it pop? Mine only does it when im under 30mph and i just wish it would do it everytime I change gear

 

[172Ben]

Its normal from cold, they run rough at start up and i believe this is why it happens

 

[182michael]

yup normal. cold start dumps more fuel into the exhaust?

 

[172Ben]

yeh

 

[Dave..]

Fairly common, just don't try taking it up to 4k and letting off. Epic bang, followed shortly by the removal of exhaust baffles.

 

[.Tyler]

Mine does it at any speed when I lift off. It's a shame that it goes away after a minute or so .

It's a really nice pop, not too loud or annoying which I think the pops & bangs remap would be...

 

[unfortunately_french]

Fairly common, just don't try taking it up to 4k and letting off. Epic bang, followed shortly by the removal of exhaust baffles.

Lol telling me not to do something is a recipe for me doing it! Have you done that then?

 

[unfortunately_french]

yup normal. cold start dumps more fuel into the exhaust?

That makes sense, so if i want it to do it more often and for longer when I get my remap i should ask them to map it rich perhaps so that more fuel gets chucked in all the time?

 

[jack_kemp]

Normal.

If you like it, get an overrun remap.

 

[unfortunately_french]

Never heard the term overrun remap, I assume that means essentially what I said, mapping it to run rich so that the ecu chucks in more fuel?

 

[jack_kemp]

Not rich, just dumps a small amount of fuel when you let off the throttle.

But yeah the pops/bangs are overrun. JMS and RStuning offer it, there's probably others too... you have to have a decat though as it will ruin a cat in no time at all.

 

[unfortunately_french]

I do have a decat as stated at top of the post, and if it will ruin the cat I assume that it's gonna be sending fuel that is still burning down the exhaust? JMS and RStuning are quite far from me I think, im in hertfordshire btw.

 

[Dave..]

don't get it mapped to pop or bang for gods sake. It'd get so annoying after 5 minutes.

I'm glad it goes away after 30 seconds, gets embarrassing.

E.g. having to drive away from a girl that you quite like one night, and not being able to help but deafen every one within 400 yards :dapprove:

 

[jack_kemp]

Aha, reading fail on my part. Unburnt fuel is sent into the exhaust, it burns in the exhaust, giving the pops and bangs.

I'm sure there's other people that do it, they're just the only two that i know of.

 

[unfortunately_french]

don't get it mapped to pop or bang for gods sake. It'd get so annoying after 5 minutes.

I'm glad it goes away after 30 seconds, gets embarrassing.

E.g. having to drive away from a girl that you quite like one night, and not being able to help but deafen every one within 400 yards :dapprove:

Lol I want it so that it only does it when coming of the throttle to change gear at highish rpm, quite a specific map required i suppose. If the girl chose to judge me just because of my exhaust i wouldn't like her anyway! I'm not looking for a deafening bang as such, just a nice pop that can be heard when close to the car What exhaust are you running fella

 

[Dave..]

Yozza.

 

[.Tyler]

I think the maps mentioned have a cut off point of 4k rpm. So if you lift off below that, no pops or bangs...

 

[unfortunately_french]

Yozza.

They are loud as f**k! i'd rather have some nice pop bangs than a constant drone that the yozza's produce.

 

[172Ben]

pops and bangs sounds w**k IMO, just sounds fake

 

[unfortunately_french]

pops and bangs sounds w**k IMO, just sounds fake

Fake in what sense mate? And they sound the b****cks imo when it's a nice pop as you change gear.

 

[unfortunately_french]

I think the maps mentioned have a cut off point of 4k rpm. So if you lift off below that, no pops or bangs...

Exactly what i'm looking for, so when i'm just cruising around it's acceptable but when I give it the beans, a nice pop on gear changes.

 

[Brian172]

I have the JMS over run map.
I think you would like it.
You can drive round town normally with no pops/bangs, then when pushed past 4k you will get the pops and bangs.
Nice compromise between practicality and fun.
If it popped and banged constantly i would of tired of it quickly, but it only does it when you want it to.:approve:

 

[unfortunately_french]

I have the JMS over run map.
I think you would like it.
You can drive round town normally with no pops/bangs, then when pushed past 4k you will get the pops and bangs.
Nice compromise between practicality and fun.
If it popped and banged constantly i would of tired of it quickly, but it only does it when you want it to.:approve:

Thanks for your reply mate, the remap youve got does sound like exactly what im looking for, so where is JMS? I noticed your in middlesex and enfield is round the corner from me which is in middlesex so im assuming not that far?

 

[Brian172]

Im the other end of Middlesex mate, down near Heathrow.
Heres a link to JMS.
http://maps.google.co.uk/maps/place?hl=en&pq=jms+tuning&xhr=t&cp=6&safe=off&um=1&ie=UTF-8&q=jms+automotive&fb=1&gl=uk&hq=jms+automotive&hnear=London&cid=16508266246352664454
They are about a 5 minute drive once off of the M25.
There map sounds like exactly what your after mate.

 

[unfortunately_french]

Im the other end of Middlesex mate, down near Heathrow.
Heres a link to JMS.
http://maps.google.co.uk/maps/place?hl=en&pq=jms+tuning&xhr=t&cp=6&safe=off&um=1&ie=UTF-8&q=jms+automotive&fb=1&gl=uk&hq=jms+automotive&hnear=London&cid=16508266246352664454
They are about a 5 minute drive once off of the M25.

Lovely mate appreciate the help, just finally how much did you pay and how long ago?

 

[jack_kemp]

don't get it mapped to pop or bang for gods sake. It'd get so annoying after 5 minutes.

I'm glad it goes away after 30 seconds, gets embarrassing.

E.g. having to drive away from a girl that you quite like one night, and not being able to help but deafen every one within 400 yards :dapprove:

If you don't like it, they'll remove it for free

 

[Brian172]

Lovely mate appreciate the help, just finally how much did you pay and how long ago?

I think it was around £160, best check with them on prices though, as they may of changed since.
It doesn't just add pops and bangs, after the remap my car drove so much nicer.
More torque lower down, and delivers the power more smoothly imo.
Had mine done in January, one of the best things i have had done to the car i think.

 

[unfortunately_french]

I think it was around £160, best check with them on prices though, as they may of changed since.
It doesn't just add pops and bangs, after the remap my car drove so much nicer.
More torque lower down, and delivers the power more smoothly imo.
Had mine done in January, one of the best things i have had done to the car i think.

Great info, so regardless of the pops and bangs in terms of power did they do any before and after rolling road to prove the gains? Or would you say the proof was in the pudding If it's £160 i'l be going down there next week!

 

[jack_kemp]

Gains in outright hp are minimal, as Brian says, it's the improved mid range that makes this so good.

 

[Brian172]

You wont notice a huge jump in power, more the way the power is delivered and where in the RPM range its available.
You wont be disappointed to be honest, the pops and bangs was the icing on the cake for me

 

[unfortunately_french]

You wont notice a huge jump in power, more the way the power is delivered and where in the RPM range its available.
You wont be disappointed to be honest, the pops and bangs was the icing on the cake for me

Hmm, well the pops and bangs would be good but was hoping for a slight gain aswell. If they said it was running 190bhp id be happy, so no rolling road print out?

 

[Brian172]

You'll never get 190bhp from a remap on a Clio.
Most standard 172/182's don't make Renaults quoted BHP figure
For reference my 172 has: Decat, Stainless steel 2.5" exhaust, Matched inlets, V6 airbox and JMS Remap, and i made 178bhp at Surrey Rolling Road.

 

[jack_kemp]

Hmm, well the pops and bangs would be good but was hoping for a slight gain aswell. If they said it was running 190bhp id be happy, so no rolling road print out?

If you're a number chaser, sell your clio

Why do people think number's are everything? You can get an RR print out if you like, you may see 3-4hp at peak, but a lot more in the mid range.

 

[unfortunately_french]

If you're a number chaser, sell your clio

Why do people think number's are everything? You can get an RR print out if you like, you may see 3-4hp at peak, but a lot more in the mid range.

Im not a number chaser lol it's just a target figure I had in mind! I didn't think it was too optimistic from a 2.0litre engine.

 

[unfortunately_french]

You'll never get 190bhp from a remap on a Clio.
Most standard 172/182's don't make Renaults quoted BHP figure
For reference my 172 has: Decat, Stainless steel 2.5" exhaust, Matched inlets, V6 airbox and JMS Remap, and i made 178bhp at Surrey Rolling Road.

Ok well i've only got a decat stainless so doubt i'll get close to that! Taken onboard was just hoping for a slightly better gain out of the remap, but will be more than happy with pops over 4k rpm and some better mid range torque.

 

[jack_kemp]

Ok well i've only got a decat stainless so doubt i'll get close to that! Taken onboard was just hoping for a slightly better gain out of the remap, but will be more than happy with pops over 4k rpm and some better mid range torque.

You'll be impressed with the difference. It may not sound a lot.....