Adjusting wastegate spring for less boost

[foxdie]

PMSL!

[Kenneth]

You could either store boost pressure somewhere (canister) but that requires having boost at some stage first.
The best bet for "free" actuation is a vacuum canister (like the brake booster, you COULD actually use the brake booster...) which stores vacuum and when activated will connect to another pneumatic cylinder or some such which will open the wastegate.

[Wodjno]

Sure we could use the spare wheel for constant a constant pressure source. A pressure regulator inline to keep say a constant 8-9 psi at the wastegate. And then a switch valve that switches at 50% throttle and above so the wastegate see's no pressure and the Boost Solenoid takes over ?

[Kenneth]

You would be better off with a dive cylinder or some such if you want to go to those lengths.

[foxdie]

How would you then replace the air in the tyre?

[Wodjno]

How would you then replace the air in the tyre?

Via a electric tyre pump that gets triggered only when the tyre pressure falls to say 10psi ? They can be set to shut off at a set pressure also.

[Wodjno]

Anyway.. Before any of the above is tried, the 1 thing to test is as Ken says! Wedge open the wastegates to see if it has any adverse affects and if any fuel economy gains whatsoever? So whose gonna volunteer to drive like miss daisy for a week

[Kenneth]

If you got to this effort, you are better off with a small accumulator (you could get one off an old AYC pump unit) and a regulator setup. This would allow sufficient pressure so that the pump only has short duty cycles (and it is useful that those pumps can generate quite a bit of pressure)

Via a electric tyre pump that gets triggered only when the tyre pressure falls to say 10psi ? They can be set to shut off at a set pressure also.

[Wodjno]

If you got to this effort, you are better off with a small accumulator (you could get one off an old AYC pump unit) and a regulator setup. This would allow sufficient pressure so that the pump only has short duty cycles (and it is useful that those pumps can generate quite a bit of pressure)

Agreed Good thinking

[Davezj]

i suggested this a wile back to see what would happen for a fuel saving option.

one of the issues raised was the compression ratio of the engine is very low to cope with the turbos. there was some issue with running an engine with a low comression ratio with out working turbos.
i will see if i can dig the thread out.

here you go,
http://www.clubvr4.com/forum/showthr...ight=wastegate

[Wodjno]

i suggested this a wile back to see what would happen for a fuel saving option.

one of the issues raised was the compression ratio of the engine is very low to cope with the turbos. there was some issue with running an engine with a low comression ratio with out working turbos.
i will see if i can dig the thread out.

http://www.clubvr4.com/forum/showthr...e-to-stay-open

[Davezj]

edit my post but glenn beat me to it.
and already posted like, you have got to be quick round here!

[Wodjno]

Well thats good info and good constructive arguments But!

The prrof is in the pudding, and the pudding still hasn't been served

[jjayokocha]

is there no way to have a seperate map for "no boost map"? it would save a lot of hassle.

[foxdie]

And it's that very reason I suggested 0.1 bar of boost, just enough to kind of break even with a bit of wastegate creep

[Wodjno]

is there no way to have a seperate map for "no boost map"? it would save a lot of hassle.

even without no boost. The wastegate spring will stiil hold shut until it reaches it's spring pressure. Thus you will get boost..

[swinks]

Well, talking about potential fuel savings - rubbish. No boost, longer applying load on engine to achieve the same thing, bigger fuel consumption in the end. IMO recent wastegate pressure is an optimum. Rather recommend you to drive for some time Galant v6, it's not as great once you apply load on engine.

[Davezj]

but the point is you will be drive in a fuel saving mind set when you activate the low boost option, so you will not be putting your foot down hard in bumble about town driving.

as soon as you want to boot it you can turn the boost up.

[jjayokocha]

well then just get a really crap spring for the wastegate and switch off the ebc and ur sorted.

[Davezj]

no you can't do that.
because as stated above it will reduce the minimum pressure achievable but when you turn it up the waste gate will not be able to stay shut as the boost climbs the EBC or other control system will not be able to bleed off/stop all pressure over 0.1 bar.