Tuning Fiat 500 900cc Twin air Dump Valve

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Tuning Fiat 500 900cc Twin air Dump Valve

turb3k

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Hello, New to the Fiat forum's, ive owned a fiat 500 lounge 1.2 for a little over a year now, However ive just swapped it for a 500s Twin Air and i wanted to ask if anyone has any knowledge as to whether you can install a Blow off/pop off valve to the engine?
I have searched google high and low and see most post/videos all relate to the 1.4 turbo engine not the 900c two cylinder one.

youtube - watch?v=7lbE-ncrGkE

youtube - watch?v=snqQVxP0H9E

Web address - bonalume.it/it/component/content/article/102-fiat/fiat-modelli/500-twin-air-turbo-dal-2011-in-poi/349-pop-off-500-twinair-turbo-plug-and-play2

Above are three links ive found that seem to show it can be done, but dont really make it 100% clear if thats the 900c twin air engine they are using :confused:, so any help anyone can provide would be welcome :worship:, also if the "Mod" affects the performance of the engine? Hope ive posted in the correct location.
 
Well the last turbo i owned was a Renault 5 GT Turbo 10years again, so just fancied the tisssssssh noise again, from what ive read on the net the recirculating valve doesnt really do a great deal as there is hardly any pressure left to recirc anyway???
 
The TA uses speed/density airflow measurement (i.e. a MAP sensor). It has a recirculating valve, and I'm not sure where you got the idea that "it doesn't do much anyway" - what do you think it's there for?

It's not to make noise, it's to protect the turbocharger from surge, and it's electronically controlled by the ECU.
 
Well seeing as most cars up to about 56 plate with turbo's did not have a recirc valve and managed just fine! How does it protect the turbo from surge? All it does is dump used air (from the turbo) back in to the turbo rather than waste it, bad points the air is warm, good points its already compressed, the only problem i can see with my quite limited knowledge of how engines work is ill loose some MPG but gain a Tishhhhh noise, but i would like someone with a good working knowledge of engines and twin air engines to confirm or deny this!?! Any help would be brilliant!
 
bgunn has a good working knowledge of the two air, that said it doesn't matter what type of engine it is as they all work the same way. If you want a tsssash noise then the only thing that will satisfy that is a dump valve, you're just going to loose performance.
 
What will cause the performance loss? Losing hot compressed air shouldnt affect the cars performance should it? As it will be replaced by cooler air that needs compressing, just means the engine will use more fuel compressing it again? Or am i totally wrong? What kind of loss? 5%?
 
It will make no difference whatsoever to performance and, given MAP, can do no harm. Running without a BOV of either type will do long term damage to the turbo. When the throttle is closed, inertia is your friend, back pressure the enemy.

Simple as that.

I've run cars with and without. No big deal, but after market recircs are usually more expensive.
 
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Thanks for the info matey, i think ill leave it rather than take any risks as the car is a 63plate fiat 500 S with twin air engine thats done 71miles so far lol might just carry on looking at things like cd player etc, as im not interested in exhaust / air filter mods really! Dont like baaaaaa coming from the car its far to irritating for me!
 
My TA recirc valve makes a 'chchch' noise when lift off. Never used to be noticeable but I can hear it clearly now. Only really heard it from 26k miles onward.
 
Well I think it's a good point to step in and say, if you have had a post removed, you can be fairly sure you have now recieved a warning for not being nice. As is being demanded here now.

Infractions come next. (y)
 
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