PIT BCU+ Boost Controller

[AderC]

After much searching on the subject I bit the bullet and went for an electronic boost controller rather than the manual option, but still decided on the cheap option and went for the PIT BCU+. Had it installed by WRD at the weekend, and there were a couple of minor problems with the kit provided (insufficient hose and wiring, and lack of mounting bracket for the solenoid) but otherwise installation went OK.

I've now had time to have a proper go at setting the unit up but am having some weird stuff going on. The adjustable settings are as follows:

Set Boost - the target boost level in psi (separate LO and HI settings).
Gain - controls how quickly wastegate opens and closes (0-100% where 100% is quickest opening/closing, and there are separate gains for the LO and HI boost). The manual says this should be set low and gradually increased until the destination psi is reached.
Start Boost - psi below Set Boost at which the wastegate opens (e.g. if set boost is 9psi and start boost is 2psi, wastegate starts to open at 7psi).
Warning level and limiter (I've set these to 14.5psi and 90% of set boost respectively).

I've temporarily set the high boost to 0.00psi/zero gain, which as I understand it will effectively turn the unit into a boost gauge and not control the boost. In high gear, uphill at WOT I get stable boost readings from 5.9-6.1 psi which I assume is stock boost on my pre-facelift auto Leggy.

I've currently got the low boost set at 9psi, and I have tried runs up and down a nearby dual carriageway (up being uphill!), adjusting gain at 5% intervals, but I can't get a stable boost level above the stock boost level. The best I've managed is to hold 8-9psi on partial throttle in 4th, but at WOT the boost spikes to 11-12psi and then falls back to ~6psi. Even weirder, I've set the gain to 20% and the start boost to 0.5psi (i.e. wastegate shouldn't start to open until 8.5psi) and in high gear at WOT the stable boost obtained drops to 3.9-4.1psi. I didn't think it was possible to go lower than stock with a boost controller but I seem to have managed it!

Anybody got any idea WTFIGO??

Cheers,

Ade

[bernmc]

How many ports did your solenoid have? If three, are you sure the correct two are being used?

The 5.9-6.1 psi is your wastegate spring tension. ie with no boost control, the wastegate opens at 6 psi.

I'd start with gain 10%; target 9psi; start boost 3psi.

[Wodjno]

With all settings at standard, do your boost characteristics act as normal ?

If it is.. ?? I wouldn't bother messing around wth start boost yet !!

Just set your target boost say 12psi and gain to 10... See how that go's..

Also if your using the Safety limiter ?? I would switch that off as well for now ?yes

[AderC]

When on standard settings the car seems to behave as expected. Will try upping the boost further tomorrow and see what happens. Didn't really want to take it too far until I'd got a low-ish boost setting sorted first.

Still can't get my head round how I'm getting lower-than-stock boost though?!

Cheers,

aDe

[AderC]

Well I've upped the boost to 12psi over the weekend and I'm now totally addicted...

I'm still having the wierd thing going on where when I run stock boost and go to WOT in 5th, I get stable ~6psi, but when the BCU controls things the boost rises intially to ~8psi, but then falls back off to a stable ~4psi (i.e. below stock). I've double-checked the connections (not that I doubted Nutter_John's expert installation!!) and everything looks OK to me. It holds boost OK under partial throttle in 3rd/4th. Anyone got any bright ideas as to what's going on?

aDe

[Nutter_John]

Let me know when your up near the garage at a weekend and I will have a look see ,

Need to know whats wrong with it as I was going to reconmend that uint to another customer but may hold off now until we know yours is working

[Wodjno]

Well I've upped the boost to 12psi over the weekend and I'm now totally addicted...

I'm still having the wierd thing going on where when I run stock boost and go to WOT in 5th, I get stable ~6psi, but when the BCU controls things the boost rises intially to ~8psi, but then falls back off to a stable ~4psi (i.e. below stock). I've double-checked the connections (not that I doubted Nutter_John's expert installation!!) and everything looks OK to me. It holds boost OK under partial throttle in 3rd/4th. Anyone got any bright ideas as to what's going on?

aDe

So when you run 12psi ! Is it holding ?? Or is it rising and falling down to 4psi ??

Are you running the stock BOV ?? Check the vacuum hose that connects to it.. I had the same issues when i 1st got a boost controller.. I could not hold any boost over standard. Mine had snapped off completely..

[AderC]

With current gain setting (60%) I can hold it between 10 and 11 psi at part throttle but can't hold a steady 12 psi (although it spikes up to over 14 when I floor it). I know the gain still needs setting correctly, but need to sort out why it's underboosting at WOT in 5th before I can do this (as I understand it).

John - can't make it over to WRD this weekend but possibly weekend after.

Cheers,

aDe

[AderC]

The BCU+ seems to have settled down a bit. I did the altitude correction reset on it the other day and this actually seems to have made some difference. I've got it set at 13psi target, 2psi start boost and 75% gain, with 14.5psi warning. It's now holding well above stock boost at WOT in 5th. Not quite holding target boost yet so some fiddling with the gain still to do - only prob is I'm only getting chance to do it in rush hour traffic so I might just leave it til the long run down to Japfest.

aDe

[Kieran]

What other mods have you got on the car Ade? Reason I ask is 13psi is 0.9 bar - Last time I saw your car it looked totally factory, and with the standard exhaust, cat and intake filter, I would be surprised to see it hold 0.9 steady?

[AderC]

Yup it's standard, but the zorst is soon to be changed as it's held together with Blu-tac and Elastoplast, and will probably change the panel filter for K&N or similar at the same time.

I'm holding a steady 10.5-11psi (which makes a hell of a difference anyway!)

aDe

[Kieran]

Probably explains it, especially if you've still got the Crap-o-lytic converter on there.

I expect it'll hold much easier with a decat and exhaust and better filter. Just be prepared to adjust again as you may see a bit of boost spiking - you'll almost certainly have to wind down the gain.

[AderC]

The BCU+ is now fully functioning. Was getting p!$$ed off with it not holding boost so I got hold of a boost tee with the intention of plumbing this in and using the BCU+ as a boost gauge only. Wasn't til I had all the piping off to install the tee and could follow the vacuum hose connections that I noticed the pressure port on the solenoid was connected to the actuators. Switched 'em round and all is now OK. D'oh!

Holding boost well, spiking a bit but haven't had much chance to adjust the gain etc. yet, so still reserving final judgment.

aDe

[AderC]

I'm actually quite impressed by the BCU+ now (bear in mind I've never used an EBC before so I've nothing to compare with). Got HI boost set to 12psi and it holds this steadily at WOT in 4th/5th. Spikes a bit on gearchanges in the low gears, but nothing to worry about (last boost showed 15.4psi when I pulled up at work this morning and I did a couple of blasts from the lights on the way).

One very minor niggle with my unit is that it's not recording Peak Boost (highest boost recorded since last reset), but it does record Last Boost (i.e. highest boost since ignition was last turned on) so I can live without the peak boost function. Have e-mailed their tech support guy who promptly replied suggesting I exchange the unit (he's not come across this fault before), but I can't be ar$ed cos otherwise it's working fine.

Fits very nicely in the hole where the clock usually lives (I've got it packed in with that non-slip rubber mat stuff), but wouldn't fit in the coin-holder thingy like the some of the other EBC's do. I prefer it in the clock's position anyway as you can keep your eyes on the road and on the boost gauge!

Gone from a "don't touch it with a bargepole" to a "well worth the £140".

aDe

[Marklar]

Good to hear its worth it!! I am currently installing an HKS EBC but still have standard BOV so hope to replace that before playn with the boost too much.

[AderC]

I'm actually using it as a boost gauge at the mo with a turbosmart boost tee. Had a new exhaust a few weeks ago so the BCU+ needs setting up from scratch again. I've got an EVO FQ300 BOV off Ebay so I'm waiting til I've fitted that before I mess about with the BCU+ boost settings again. Don't want to have to go through the set-up process again twice!

Must comment that the Turbosmart boost tee does work very well though - holds boost well and doesn't spike too much. The only thing I miss about the BCU+ is the in-car adjustment!

aDe

[AderC]

Finally got round to fitting the FQ300 BOV I got via ebay in November while the oil was being changed. WHAT a difference! Any criticisms I had about tuning the BCU+ can now go out of the window as I've got both the LO and HI settings more or less there within 50 miles of driving to and from work. Boost builds up nicely and holds well too. Bit of tweaking still to do as it spikes a bit when dropping by more than 1 gear but is fine from a standing start.

aDe

[Kieran]

Shows how rubbish the stock BOV is, eh!

[shrew]

On that subject...

ive had a blitz vta on hard pipe fitted for the last few months to try out before upping the boost levels, and instantly felt that it was stronger through the midrange and ultimately quicker through the gears.

so likely evidence that my stock recirc valve was already weakening i think, but without any real noticeable defecit or symptom.

just goes to show that sometimes fixing what you don't THINK is broke, still can be very worthwhile.

just want to get some more boost through, NOW!!!

cheers

shrew

[ҢдщҚ]

Has anyone got an install manual or anything for this boost controler. I cant find anything, the websites not up atm and no reference to it anywere. I would be most greatful if somebody could shout me a copy ;-). Thanku thanku hehe..

Also any updates on how this device is working. I guess as no updates you have'nt ripped the unit out ? How's it going day to day driving ?. Only thing is shrew's car is up for sale and if i buy it i get this with it and i am trying to get as much info as possible.. .. .

I really need that install manual. There was never an instruction manual as far as i am aware !

Thanks in advance..
Steve...