Boost control problem

[immy21]

I am using the stock solanoid to control boost on my S14a. It works fine in 1st, 2nd, and 3rd gear however on 4th and 5th it bleeds regardless of what is set in the boost maps meaning I cannot reach my target boost, I guess this is down to the stock setup of bleeding off in the last 2 gears.

How can I stop it bleeding off in the last 2 gears?

Another question, what is bit 1, 2, and 3 in feedback switch/feedback control flags?

[Matt]

Not sure on the unmarked feedback flags as I havent gone that far in the disassembly

With regards to boost control I havent experimented with S14A so cant comment directly on that one, unless someone else has something to offer. There were some older threads with regards to boost control on these by Chris

[PL]

What turbo and what boost? You may find that it's just not capable of delivering what you want at high load/rpm??

PL

[immy21]

Iv read through the two main boost control threads, one of which had Chris doing some good testing. At no point did anyone including Chris and PL mention anything about having this problem. Im wandering is having 7psi in 1st, 2nd and 3rd gear then the solanoid raising it to 10psi for 4th and 5th an euro thing?

On an unrelated note does this look right?
Iv not fiddled with any of these but having VTC tp cut at 24tp sounds to me VTC will be cut at hardly any load.
Also VTC cut at 0kph, does that mean it will not cut at any speed or will cut as soon as the car is moving therefore disabaling VCT?

[immy21]

What turbo and what boost? You may find that it's just not capable of delivering what you want at high load/rpm??

PL

stock t28, peaking 17psi (with ball and spring), Forge adjustable actuator with 14psi blue spring set to roughly 13psi, usual HD stage 1a bolt on mods (if your familiar with them)

I plumbed it in as a block setup so boost to solanoid to actuator (ball and spring removed). zero'd the entire table. I got unlimited boost in the first 3 gears as expected but actuator pressure in 4th and 5th

Another question if you don't mind, I cannot for the life of me find injector duty cycle, were is that hidden please?

[PL]

T28 on an SR will only give 15 to 16 psi max at high rpm/load. Less if exhaust/IC isn't flowing well.

Make sure you have Injector Duty Cycle checked in the list of parameters when consult connects.

PL

[immy21]

I think you misunderstood me
With the MBC I set it to peak at 17psi and then boost tails off to around 14psi by the redline so that is fine.

With, MBC removed and the solanoid fitted to block, and boost map set to zero I cannot get past actuator pressure in 4th or 5th which is currently set to around 13-14psi on my Forge adjustable actuator, regardless of RPM, so even around 4k RPM on WOT it will not go past 13-14psi.

Do you have gear dependant boost in stock JDM and AU S14's?

[PL]

They don't have a gear position sensor - just neutral and reverse. So there's no gear dependant maps.

Unless the boost maps are speed dependant??

I must admit I haven't done an S14a with factory boost control - only an S15. Worked fine on S15 and from what I've seen S14a and S15 are very closely related.

Sorry I don't have more info than that...

PL

[immy21]

Thanks for the replys, it's a shame I can't get this to work.

I looked at the speed limit tables, all 3 are in warp territory so I guess it's none of them.
What do bit 1, bit 2, and bit 3 in the feedback switch flags do?

I also forgot to mention, only the far right load colum (240) is ever being accessed on the boost map. TPS seems to be functioning correctly according to logs however nothing seems to affect the 'load' on boost maps including throttle postion.

[PL]

That's weird about it only accessing the last load column. I'm gonna have to do some S14a bench testing. It took us a bit to get S15 boost control maps correct, so maybe there's more to S14a than meets the eye too. Generally S15 = S14a so I'd be surprised if they differed in the boost control area.

PL

[immy21]

It's something I wasn't expecting to happen after reading through the boost control threads. I have attached my map and log above.