Help with Boost Controller?

[xaero1]

Hey people,

Can you help?

I've got a Blitz SBC ID boost controller in my car and on my old R32 engine it seemed to be working fine. It held boost at 0.9 bar and only crept up to 1 bar if I was at high speed.

However now I've got an R34 engine and turbos it just won't hold the boost correctly. I've got the boost level set at 0.8 bar, but when accelerating boost sticks at 0.6 bar all the way up to about 6500rpm then it creeps up to 1.1 bar

I can't win. If I set the gain any lower it boosts too high, but if I set the gain any higher it's too slow to boost.

The car still feels quick because the R34 turbos boost so early, but if I could have 1 bar all the time I'd be much happier.

Are there any other settings I need to check in order to sort this out?

Or is the boost creeping due to the R34 turbos and my downpipes? I've heard somebody else mention that their R34 turbos overboosted due to downpipes.

Any help appreciated.

[xaero1]

Anybody?

[mifn21]

Is there a way of resetting the boost controller? Some of them (ie the AVCR) are self-learning
Could also try bypassing it and seeing how the turbos respond to being controlled by just the wastegates

[Addicted2Boost]

Hey mate, i have a Blitz SBC id III in my R34 and if you have a look at my thread i was having similar problems...

Even now, to be honest im still not entirely happy with it. What other supporting mods do you have? I was told by a well known tuner in NZ that if u have aftermarket downpipes with the standard turbos on the R34, they are prone to boost spike...

As for ur boost problems im as confused as well. I know for twin turbo setups the instructions says u must use manual settings and not auto. But on auto mode, the rush seems so much stronger in the seat... but is prone to over boosting but 70% of the time its good...

On manual mode doesnt overboost as much, and doesnt feel as fast, just progressive... and after reaching peak boost of 1.2bar, it settles back down quickly to 1.0-1.05bar... i wish it cud reach 1.2 bar and it will hold it rock steady there but it doesnt... on manual setting i have the gain as about 4-5 (low i know... ) and the ratio on 56. After a lot of playing and boosting it seems good there, 57 overboosts too high and 55 not enough...

I only have a full exhaust (not including downpipes) and power FC.

Hope that helps.

Also a pair of HKS actuators might help too in controlling boost more steady... let us know how u get on, id me interested as well

[xaero1]

Thanks for the suggestions guys.

The mods I have are downpipes, decat exhaust, boost controller and induction kit. I think the downpipes do have something to do with the problems and I honestly don't think I can program the controller to work any better.

I'll have a play with the ratio briefly and see what results I get, otherwise my only other option might be to get a boost controller that plugs into the ECU as well. Then I'd have better control

I'll update the thread at the weekend. Cheers.

[kgleeson]

I would stick a mechanical boost controller in for what you need and sell the Blitz one. Pick up a a good NEW mechnaical boost controller for £25. Will spool qucikly and should hold the required boost all day

The more popular electronic boost controllers seem to be the AVCR or the Greddy profec B which looks like the same solenoid as the AVCR.

The Apxi boost control kit for the PFC works Ok but not as good as the AVCR.

Kev

[xaero1]

Update.

I spoke with a few garages and the opinion is that on the R34 turbos the exhaust housing is too small so when you get decat exhausts and downpipes you don't have enough back pressure to stop the boost spiking. I hope that makes sense to you because I'm crap with stuff like this!

Anyway, Abbey recomended putting in a small restrictor in the exhaust to stop this from happening.

It looks like i'll get that done then replace my ECU and boost controller completely. Better to be safe than kill another engine!

[kismetcapitan]

that was my feeling - the turbos were spooling to what *they* wanted to be at, wastegates be damned. Turbos are like that, and I do recommend a mechanical boost controller - the self-learning on my Power FC just makes it worse and I've got to reset it (unlearn!) every week or two to get nice fresh fast spooling with about 0.08 bar overboost. My boost control is set to 1.85 and it (when unlearned) quickly but consistently hits 1.93. But as it "learns" it dramatically slows boost buildup to gently reach 1.81 or 1.82, or god forbid, 1.75!

[nozza1]

'xearo1' any luck in eliminating your boost spikes.