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hey i have a BCU+ boost controler on my r33

it holds boost fine at 7psi (low) and even at 11psi (high)

if i jump on the power in low revs it spools and holds 11psi fine but when i do a quick change or punch in above 4000 it spikes like crap to about 14-15psi

is this a tuneing issue or is it just shit?

the only reasion i have it was i got it really cheap

please help!

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hey i have a BCU+ boost controler on my r33

it holds boost fine at 7psi (low) and even at 11psi (high)

if i jump on the power in low revs it spools and holds 11psi fine but when i do a quick change or punch in above 4000 it spikes like crap to about 14-15psi

is this a tuneing issue or is it just shit?

the only reasion i have it was i got it really cheap

please help!

Have you played with the gain, or are the settings out of the box (or auto) - list the the type of BCU and EBC you have. Did it only start doing this after your BCU and EBC? :)

Edited by GeeTR

yer i have played with the gain and start boost but haven’t found a good combo

i had a turbosmart boost T before was spiking too!

the car has front mount intercooler

3" dump hiflow cat with 3.5" cat back

iridium plugs and splitfire coilpacks

i want to run about 12-13psi standard turbo but need to stop the spiking

anyone tuned one of these before

any suggestions?

the BCU+ boost controller can be seen here-

http://www.sportcompactonly.com/Boost-Cont...115_p-79669.htm

LoL, i was quoting "BCU" to take the piss, butt they actually call it a "BCU" :):D

Checking the specs, id say its just a EBC :)

A spike is were boost overshoots target boost for a moment, then settles again, usually due to aggressive gain.

Does yours temporally hit 14, or does it stay rock solid at 14??

Its your gain mate.. What is it set on?

Its difficult to set up originally but put down about 6gain and then dial in 25 on the controller this should net you about 10psi

Dial up the boost to where you want it and then turn up the gain and floor it, take note when it starts to spike and turn the gain down.. then your set..

Make sure you've regapped your plugs to 0.8 too cheers

ok reading this makes me almost certain there's something wrong with my ebc ... it's set to 10psi but the lcd display shows number ranging from -99 up to low positives (it should go to 100 as that's 10psi on this ebc) , going up and down quickly (NEVER settles even for a second)

Weird thing is when they installed it at the shop and put the car on the dyno ..according to their graphs it was holding 10psi. Ah wtf. this is getting ridiculus ...the more money I spend the more problems creep up that I have no friggin idea how to fix.

cheers guys i had a play with it for about an hour tonight and seems much better but still spiking

i got the start boost set on 10psi and the gain set at 60

its going straight to 11-12psi and holding great

but when i take it to 7000 and kick it into 2nd and jump back on the power it still spiking to 13.5-14psi

i got my warning set at 14psi and it hasn’t been going off

will play with the gain abit more tomorrow night to try to get it sweet

but if you have any advice on tuning it please tell!

ps. iridium plugs at 1.1mm seem fine as long as you have splitfire coils

  • 1 month later...

Hi, I know this thread if old but if your still having problems.

The BCU+ unit's start boost function works like this.

Lets say you set boost at 14psi, and start boost at 10psi, what it means is the wastegate will start to open 4 psi.

If boost is 10 and start is 10, it will open straight away.

Its quite a tough unit to tune, have been using it more than a year and the soilenoid stopped working on me today. Took it apart, gave it a nice clean and now its working beautifully again.

I find setting the gain from low then slowly increasing it till it holds boost till redline better, although many people go from up to down. And its sensitive as well, 1-2% gain makes alot of difference. Good luck.

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