Just fitted a forge VTA to my MY00 classic.

Just wondering as i have heard people say that they can cause overfuelling, will this affect the emissions test at MOT time?

Has anyone had problems with VTA dump valves and emissions?

I have also noticed at idle the holes at the side of the DV are open? Is this as it should be?

Cheers

 

no problems at mot time..... have the same on mine,the holes appear to be open,thats where the air vents out,but the valve is closed inside until the air pressure overcomes the spring


Can cause overfuellng issues in general running due to the air thats already been metered at the maf being vented out when lifting off or changing gear,the fuel thats then still being injected into the engine to match the metered air is then greater than it should be so yes can overfuel..... but not gonna be an issue when tested for the mot as revs are held at a constant value to check o2 and lambda readings....

 

Cheers rigga

Thats a relief as my MOT is due in a few weeks!

How can you tell if overfuelling is occuring? Are there any symptoms?

Mine seems to be running fine at the moment

 

Its just the general opinion,and seeing how the dv works by venting metered air out then its easy to see that it can cause overfuelling issues,but to be honest ive not noticed any problem,i fitted the forge to a newage intercooler as it was easier than trying to find pipework that would match up the different sizes that classic and newage are..... or at least in my case,others have managed to do it,when the car was mapped there was no problems with fuelling.

 

talking of MOT's.. how far in advance can you get one done? Mine is due but I am on holiday so need to get it done before

 

Month in advance as far as i know,so you can get it post dated so your new one runs for 13 months......(might be two weeks though...... been out of that game for a few years now)

 

30 days

 

Before fitting my VTA dump valve i was only getting 0.8 bar of boost (under boosting as i have PPP) but since fitting im getting in between 1.0 - 1.1bar...Why is this?

 

dump valve should be nout to do with M.O.T.

 

NOUUT TO DO WITH EMMISIONS MATE. AS LONG AS YOU HAVE A CAT, YOU WILL BE OK

 

Cheers

Anyone know a reason why the dump valve has increased the boost slightly?

 

could be that because the VTA is dumping the air out making the turbo spool better!