Minimum Boost?

[CanisLupus]

I know it's a strange Question

What's the minimum Boost i can get with a Boost Controller and the following changes:

 

3" Catback exhaust, 2nd Cat decat on stock Twins?

 

I know with double decat and restrictor Ring about 1 bar is minimum but with only the second Cat away?

Point is i want to restrict the boost if my GF is driving it, i just want to cruise around or i give it away for repairs.

 

cheers

[jevansio]

A boost controller can only raise boost levels, not drop them

[CanisLupus]

No way to open the Wastegate earlier? I mean the Apexi AVCR can go down to 0,15Bar if i want just the question how much downwards would the boost go?

[jevansio]

No, to do that it would have to generate pressure of it's own accord & it can't do that

 

AVCR can't do that, it might say that on the display but it won't go that low

[CanisLupus]

So the minimum would be stock right? Is there a way you could make it lower than stock?

Small pump or smth like that?

[SupraDan24]

Why would you want too???

[jevansio]

So the minimum would be stock right? Is there a way you could make it lower than stock?

Small pump or smth like that?

Yes the minimum is stock. I don't think a pump is feesable TBH

[CanisLupus]

Why would you want too???

 

Mentioned above.

If my GF gets her hands on it(the probable case) or i give it somebody for repairs(not realistic but could happen).

 

 

Thanks guys, i'll have to stay with stock as minimum then

[Suprab1]

If you run 3" cat back with just the 1st cat in i'd say you will see about 1 bar boost.

 

Your best bet is keep every 1 else out of it

[Willson]

Mentioned above.

If my GF gets her hands on it(the probable case) or i give it somebody for repairs(not realistic but could happen).

 

 

Thanks guys, i'll have to stay with stock as minimum then

 

I think you could put a temporary lowered rev limit in if you had a suitable ecu?

[Scott]

With a double decat I can't see you managing stock. You are limited by the restriction in your system. In you case a 1bar restrictor ring. You shouldn't go any lower really, as adding more restriction will only generate heat (The reason you don't go for 1.2 bar with the cats in).

 

What you could do is wire up the wastegate actuator to stay open at the flick of a switch? This is purely theoretical but I can't see why it wouldn't be possible

 

This would mean your tubby's wouldn't build any boost at lower RPM and the RR would mean that 1bar would be the max even at full chat. I can't see your girlfriend driving the car like that though

[CanisLupus]

Thought about it but i still have the stock ECU. But planning on getting an AEM Series 2 next Year. Can the AEM do something like this?

 

I tried a little bit tonight. I set the AVCR to 0.45 on 20% Duty.

Minimum was about 0.6ish with first Turbo when Second came online low 0.8 but i don't know if it is just a spike cause i only read the peak values for each try.

 

Tomorrow i'll try some more and with logging this time

 

EDIT saw your post after me posting Scott:

Don't have the double Decat and can't do it here in Germany or i'm F******(sorry for the bad word ^^) the next step would be an 3" Downpipe with 100 or 200 Cells but this is a couple of months away. Other things(brakes at first oO) have more priority

Edit2 how would i do that with the Switch? ^^

Edited May 29, 2010 by CanisLupus (see edit history)

[Scott]

Ahh, I read it all wrong. I thought you had the first Decat and were just about to put the 2nd decat in.

 

Without the 1st decat you really don't want to go over 1bar. The lowest reading you will get is with the boost controller turned off altogether. You can open your wastegate mechanically bud, no need for any fancy ECU gizmo's.

 

Not sure if it would work the way I describe as I haven't thought it through properly but it makes a bit of sense

Edited May 30, 2010 by Scott (see edit history)

[Swampy442]

As above, you cant lower your boost below the stock actuator boost pressure

[trinitom]

Just buy an N/A and problem sorted!

[CanisLupus]

@ Scott 1 Cat is away it's the one further away from the engine. It looks like the previous owner just kept the stock pipe and welded in another piece instead of the 2nd Cat. Hope i can get Bradleys Blitz pipe instead with begining of June. ^^

The first near to the Engine is still there

 

@ trinitom Naaah TT is fine with me but i see the way my GF is looking at it and wanting to drive it

 

Today i tested again a bit and saw what i wrote already.

1. Turbo alone about 0,65 and when the 2. Turbo comes online there is a little peak to 0,86 and then about 0,8. So confirmed no lower than stock possible

 

I'll just have to get the AEM asap so i can set a rev Limit

[trinitom]

you probably have a leak somewhere, stock pressure on 1st turbo should be 0.74.

[CanisLupus]

I'll take a look but i don't think so. Everything else is working fine. ^^