5 Re: Hi flow BOV 18th November 2016, 12:37 am
Yes as mr b said really Dan
Worn throttle bodies are a big concern with these cars now and it looks like sometime in the past yours have been badly messed with as the idle screw adjustment is very chewed up so maybe someone at some point has messed with the 4 main vacuum bypass screws.
When it was mapped i adjusted the idle via the datalogit but ideally its far better to make adjustments via mechanical means. Whether thats whats causing the issue or not i dont know at this point so maybe try the simple things first.
Heres the things i would go around sorting first
1. As your doing..... better quality vacuum lines with minimal & shortest possible
2. Fit wideband noting when chatter occurs if afr's lean out or goes rich (we never had the issue on dyno or test drive after so worth checking) fantastic bit of diagnostic kit and to me a necessity especially when your running a lot of power.
3.boost controller......now i know the gizzmo one you have works all ok but it is not really good enough to cope with that higher boost level in controlling surge so i would personally look for something better suited such as Apexi avcr etc which has much finer adjustments
4. Wastegate springs.....as you said you have used multiple springs to get to .9bar but if your running 1.7 ,8bar then i think the progressive rate of each spring will be different which could cause wastegate chattering at higher boost levels so i would ditch the various springs and go for just the one 1.2bar rated spring then make the adjudtments around that with boost controller
Hope that dheds a bit more light on it Dan
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