UK blow-off valve poll

Following on from the thread about UK cars with SSQVs and other dump valves being prone to stalling/detonation, I thought I'd find out who's got a dump valve, and if they've experienced any problems.

Seb

tries to stall sometimes when really cold, weather has to be icy etc. though.

at what point would i need 0ne of these as im not a ricer and will buy one if and when the stock item cant cope any longer.

anyway im happy enough with the sound of the stock one through my hks filter:p

Sorry voted before I opened the thread then saw it was refering to UK spec cars, I have a JDM car so my "Everything is OK "vote does not count.

im not a ricer

Pffft!

at what point would i need 0ne of these as im not a ricer and will buy one if and when the stock item cant cope any longer.

anyway im happy enough with the sound of the stock one through my hks filter:p

When you junk the stock sequential system.

-Ian

I have a standard dump valve and everything runs fine as far as I can tell

That's a recirc one though, not really a dump (to atmo) valve

-Ian

Pffft!

shouldnt you be tucked up in bed with your hot milk

HKS do a recirculation kit for the SSQV to get over this issue. See here! Dusty lists them for the Supra on the MVP site.

ive got a hks vpc now so i can have a dump to atmosphere BOV with no problem now

My stock recirc is now starting to goose honk! Whats the best replacement if I want to keep it as a recirc but change from stock? No pssshhhttt pssssctttt here!

If i am not mistaken, doesnt the UK spec have an Air flow metre along with a MAP sensor, from bitter experience with many cars, air flow metres do not work well with atmospheric dump valves. Simple non tec explination is that fuel is mapped to the volume of air passing the air flow metre, this air that has been accounted for is then lost to the atmosphere when the butterfly closes and the dump valve opens causing a sudden loss in the predicted fuel map.... Hence causing irratic engine response. Jap spec cars with only a MAP sensor that is located in the Plenum chamber do not suffer as the fuel is only mapped once the air has gone past the butterfly hence loss of air through an atmospheric dump valve has no effect what-so-ever as the air loss is BEFORE the butterfly. Hmmm.... tried to keep it as simple as poss. Sorry Also as it happens, cars fitted with a Matrix or Vortex style Air Flow Metre systems are far less prone to this problem... Things like Mitsubishi Gto TT's etc.

Yep, that's pretty much it - FAQ entry here

Toyota sensors are hotwire. The other problem I found is that the splugs get fouled so cold starting becomes problematic.

You can get around this problem with the anti-stall features of airflow mappers like the AVCr and E-Manage.

-Ian

Yep, that's pretty much it - FAQ entry here

 

Toyota sensors are hotwire. The other problem I found is that the splugs get fouled so cold starting becomes problematic.

 

You can get around this problem with the anti-stall features of airflow mappers like the AVCr and E-Manage.

 

-Ian

ian, can you adjust the cold start fuelling? since fitting my vpc/gcc (all zeroed) my car has been running really rich and i cannot drive the car without warming it up first. it just cuts out as soon as you touch the accelerator.

I'm working on it I have no experience of a VPC so I don't know how that does what it does. The E-Manage can't adjust cold start per se but there looks like a way of doing it. Can't say anything else because it might be bollocks, it's an ongoing investigation...

-Ian