I've got a flashed k24 Gt2 with an exhaust (Europipe) and a set of EVO waste gates. I've had the broken actuator rod issue, (third set of improved rods with no issue so far). When the temperature is 60 degrees or warmer, the car boosts to 1.1 in second gear and third and briefly 1.2 in fourth. When the temperature drops below 50 or so, the colder air creates a brief overboost (1.3 spike) and I can feel the fuel cutoff for a split second.

The ECU then makes an adjustment and the car will remain at about 1 bar with the occasional spike to 1.1. My question is this, if I switch over to a modded K24 (i.e. 24/18) and a new flash program, will this solve the problem? Do the 24/18's have a different waste gate installed that will solve this problem? Is this a problem as long as you remain with a rod? I would assume that an external wastegate would solve this issue.

I don't want to go to a boost controller and remove the ECU's internal protection, but it is frustrating when you take her out in a cold air environment. Any suggestions out there, since I am about to move to a 24/18 set up this spring, no more dickin' around.

 

maybe your wastegate adjusting is not correct (little overtight) adjust it at first .....this should result in more power corse the ecu don`t retard timing and boost in cold air conditions

 

Unfortunatly that is the negative side of using 1 bar springs.
I have been thru this 5 Years ago testing all sort spring rates and sadly to say It will get worse wHen it gets colder. A tuner can play a little with the boost bit since ur springs are so stiff it's really a loosing battle when it gets cold.
As far as the boost controller and losing the safety running one. Sorry but the ebc has a built in warning feature as well. It even beeps flashes and even pulls back the boost to a user pre determined boosT setting. Sure some tuners are against it because they do not sell it as a package they offer. His my question is what solution do they offer to someone like you who will overboost to 1.5 bar when the temps drop to 40 degrees.
I always said that a 1 bar spring is too stiff for a 1.1 to 1.2 bar Heck I'm getting that on a customers car with stock springs and he is on 18gs.
Over the years I have found that clients with a ebc are more careful with their cars then those without. But that is just my opinion

sorry for typos on a phone remote.

good luck
mark

 

I'm not sure how one answers the question WITHOUT knowing the details of the flash!!!

What does the person who coded your flash say? (ie wrote the programs)

 

Kevin,
are your wgs springs you carry 12 psi or 1 bar? heard good things about them...

As far as the EBC vs stock ECu and the blown motors... I agree but most guys running higher HP numbers do run EBC.... that alone induces risk... and even some have built motors as well...
Most guys I know are really careful and when taught properly they love the EBC because in a situation like this one when the temps drop you actually lower the boost by clicking a **** and your done... but like I said this is just my opinion.... and I do not think a 500 rwhp car needs a EBC... On top of all that a program needs to be written to use the EBC properly.... just like for after market WGs...
mark

 

For this cold weather overboost i would make a test....

disconnect the control valve from the ecu (only a grey electr. plug) and check the boost....this boost is the lowest boost that the ecu can regulate...if this boost is to high, you must adjust the wastegates to a lower and safe boost situation...(with the right base setup for wastegates)

if you reconnect the boost control valve after adjusting...now the ecu have spectrum to regulate to the tuner programmed boost ...if the boost in basis is to high (overtight wastegates), the ecu has no chance to retard the boost to a safe situation in cold air conditions...imho



hope i find the right words .....

 

Kevin, so the issue is the programming? When I move to 24/18's will the new programming prevent spikes during cold weather? Does that mean that the programming will prevent the spike or compensate for the weather and still let the boost come on normally (1.1, 1.2) or will it sense the temperature and reduce the boost (1 bar)?

I don't really drive the car much during the winter, so I don't experience it much. I hope I'm not damaging anything, but I think the ECU senses the overboost and compensates to prevent any permanent damage. Am I wrong?

 

Your tuner has to be able to do it... and I can tell you that with 1 bar springs in cold it is hard to too.... hence, if you open up the WGs to lower the start boost you may open too much and have it bleeding all the time... not good...
We do this stuff but when a tuner doesn't sell you the turbos with his WGs he doesn't really have all the control over what is happening.. its like you putting on 3rd party products expecting someone else remotely to dial in the car ... it really is not that easy... I helped out a friend with gt28s he bought that had the those same WGs... we spent 3 days fiddling and retuning the car ... in the end it was a losing battle.. we gave up.... and that was with the tuning ... unfortunately the stiffer the spring the harder it is to control at lower boosts.... mind you you get a stiffer one to run more boost not less... a 12 psi springs seems to be a good compromise....
you could simply put on stock ones for winter...

 

Mark, does this problem still occur if you have external waste gates? I would assume that they are controlled by the EBC.

 

for example we run .8 bar springs on Tial 44 mm Wgs... thus minimum boost it will run is .8 bar... at 32 degrees the other day I seen .9 bar.... I datalogged the car.... so I know... in 70 degree you will run .8 bar...
however running an external one does not have to worry about setting up the correct rate... it simply runs the .8 bar period... now you induce a EBC and you can take them to 2 + bar... dial in any boost on the go... you even control the rate...... you lower the set gain and you also lower the TQ....
basically you run a .8 bar spring that dials in 3.5 times that on the go and holds it.... no bleeding thru a flapper like in a internal WG set up.... nor are there any rods that bend nor break...
I took a pic of one when I was taking some pics for the site...

 

Not sure this is right....

Without the input from the N95 valve, the car will run at maximum boost (this means the boost derived by the turbo speeds, etc...not the 'numeric max'). The computer can ONLY REDUCE the boost- it cannot increase boost over the value obtained by the mechanical spring.

Right?

 

No, I thought that the externals would solve the waste gate issue. I know there are a lot of members on the forum that live and drive in the cold weather. I'm surprised that others haven't chimed in. Am I the only person experiencing this issue?

 

This has been around for some time.. nothing new...

 

I believe you have that backwards. The ecu cannot lower below the mechanical limit of the wastegate actuators(let's call that 1 bar upgraded actuators), only increase it.

Justin

 

Uh...that makes no sense...the wastegate is a safety release for too much boost....the ecu can certainly control below that release (i.e., not reach the critical boost pressure)...the ecu cannot go past the limits of the wastegate ...that is it can ask for boost, but if it reaches the wastegate threshold...open sesame. Of course if your springs are too strong for the rest of the hardware...it could be problems.

Kevin and Markski gave the info you need.