View Full Version : exhaust crackle and pop
andyedwards
24-02-2003, 10:04
This isn't a very grown up question but...
Does anyone get much in the way of exhaust crackle and pop or even a slight burble on overrun or similar conditions from their 20VT? Apart from the usual exhaust note mine's very refined.
Having a miltek exhaust and high flow cat I would have thought something might find it's way through.
My cousin's scubaru is a prime popper so to speak, especially after it's nicely warmed. Totally different engine of course but I would have thought similar principles apply.
I get some lovely poppage from the Jetex when the engine is warm and I change up under 4k.
Makes me :D everytime! Lurrrvly!
andyedwards
24-02-2003, 10:26
Is that just the rear box or a complete cat back system?
The standard exhaust on my 8v used to burble quite well, but no banging and popping. I know what you mean, I also have a mate with an impreza and a scoobysport system and it sounds great.
max_torque
24-02-2003, 10:43
The "popping" and "banging" is a result of the scooby having a very "lazy" overrun fuel shut off strategy, and cause it runs a retarded ignition timing on lift off to maximise turbine energy. It's easy to do with a remap - the down sides - your catalyst is going to age really quickly with all that unburnt fuel being shoved down it's neck - Most hard driven scoobys will have a dead cat by 60k miles!
andyedwards
24-02-2003, 10:50
Superb answer! I'll cross it off my list then.
Originally posted by andyedwards
Is that just the rear box or a complete cat back system?
Its a Cat back system. I won it in the competition on here. :D
I have no centre box at all, and it pops really lovely. Extra mega bang when you hit the rev limiter and release throttle at the same time.
andyedwards
24-02-2003, 11:10
hit the rev limiter!! Damn, I don't think I've ever hit the limiter, where is it? about 7K?
Originally posted by andyedwards
hit the rev limiter!! Damn, I don't think I've ever hit the limiter, where is it? about 7K?
What are ya doing then?! :D It's around 6.8k (stock).
Originally posted by andyedwards
hit the rev limiter!! Damn, I don't think I've ever hit the limiter, where is it? about 7K?
Try harder!! Done it quite a few times in 2nd and once or twice in 1st. Usually when I'm giving it some and needing to keep my eyes on the road in front of me and my hands on the wheel.
Can happen quite happily when you are driving quickly and your front wheel/s lift off.
andyedwards
24-02-2003, 11:48
I like to keep it in the power band :) Feels pants past 6-6.5K :p
My limiter interrupts my power band :D
andyedwards
24-02-2003, 11:53
lol.
Using MBC, it'll feel quite well after the 6k mark, too.
Originally posted by Sim
Using MBC, it'll feel quite well after the 6k mark, too.
What's MBC when it'a at home then? It's not Milltek Cat-back with the initials muddled up is it? :D
hehe, no. It stands for "Manual Boost Controller". Only fur turbo equipped cars ;).
andyedwards
24-02-2003, 12:29
I thought after 6K the standard lego turbo on the Ibiza 20VT started to be a bit soft for the job due to its minor size resulting in restricted flow ability?
Originally posted by andyedwards
I thought after 6K the standard lego turbo on the Ibiza 20VT started to be a bit soft for the job due to its minor size resulting in restricted flow ability?
Yes, it is. I couldn't push the boost above than 12psi (~0.8bar) after 6K, but it still goes better/smoother than "chip" driven.
ibizacupra
24-02-2003, 15:16
I keep hitting my limiter in 2nd.... 7500rpm... Opps! :D
Just gets there so quick.. :)
Bill
Tony2Quick4u
25-02-2003, 08:47
had my full cat back Magnex exhaust for a couple of months now, starting to get very poppy and crackly when i jst let the revs fall, i drive around at night now, revving it and letting it drop with the window down, sad but it sounds luurrrvely!
:D