been offered 2 dump valves 4 my ztt.Will i get any positive gains out of them, will they improve the running of the engine or do they just make a noise?! :confused:

just make a noise with a possible loss of power over the stock recircs ;)

More for noise TBH .. As I understand things they will help the turbos but the recircs are better, I would only replace to get rid of goose honk noise if it bothers you.

 

I am going to fit some myself when I get round to it (soo much to do) , but I hate the goosehonk after fitting a Blitz induction

I had been told that dumps can also cause a problem when used with an airflow meter as on the z, as the air is vented off to atmosphere but the fuel is still metered as if it was staying in the closed circuit, so you can get huge backfires or cutting out on upshift. I also heard that some modified ecu's can take care of this... :confused:

i think the stock recircs can only take a certain amount of pressure (when you start to up the boost) before youre forced to use bovs. they sound good tho ;)

What pressure can they take? ... 9psi I guess .. up the boost to 1 bar then I guess things go a bit wrong

What pressure can they take? ... 9psi I guess .. up the boost to 1 bar then I guess things go a bit wrong

 

recircs?? nah! they'll take quite a bit more than that. i run at 16psi on stock recircs. there good for 20psi+ in good nick, & theres a guy on TT.net that does an upgrade kit for them! ;)

TBH i dont know Chris. i suppose you could look around at the high-powered rides on this forum and see whether they have BOVs or not. id imagine they could take a bit more than standard before exploding!!

recirc valves as fitted OEM are better than dump valves up to approx 600bhp http://www.twinturbo.net/ttnetfaq/FAQpages/bov.html