My car is way too fast for safety...literally. Boost limit doesn't hold.

[kenikh]

"Bull Zork"

[Ronnie's.930]

^^^

Ha! Hilarious right thar!!!

[mark houghton]

Now that you've received all the input you need to deal with your problem.....well, what kind of problem is that? A fine example of German ingenuity that's TOO FAST? We all LIVE for that, spend all sort of cash to ACHIEVE that. Suck 'em up, grow some cojones, put the pedal to the metal, hook 'em up dude.

But only provided you don't hear the death rattle. Ditch the EBC, put a 1.0 bar spring in there and call it quits. It's all we really need to have an additional measure of fun and takes one more failure variable out of the equation.

[kenikh]

The death rattle is scary. I heard it today. Never want to hear it again.

[kenikh]

And to be clear, the car is NOT too fast. The only reason it is too fast is that at umlimited boost, it is too fast for the engineering tolerances of the motor, given the death rattle.

At least everything seems to have stayed intact.

[Ronnie's.930]

Kenik, so you no longer run the overboost circuit? Hows come, bro?

[kenikh]

Tec3r powers the fuel pumps. Overboost is out of the circuit.

[kenikh]

Days like this make me think EFI.

[Ronnie's.930]

Ah, I forgot just how "not stock" your car actually is!

So no over-boost protection capability at all with that setup?

[kenikh]

If running EFI, it'll fuel cut to the injectors at a set MAP kpa.

[Ronnie's.930]

I'm getting the feeling that you are going to beat me (not like that) to the EFI punch! Fookin' Norm's already there, tha' bisch bastage!

You could always make dummy metal fuel lines that looked like you were running MFI.

[Alan L]

Do you not have any overboost protection? If you have detonation (veeery bad), what level boost are you getting and what did you set the control at?
Something is going to go badly wrong here.
My EBC delays the boost signal release on top of the WG. Works perfectly . But the good advice (Mark) would be to put a 1 bar spring in and forget EBC if you have these issues that can't be resolved.
Next thing we will be reading your rebuild thread :-(
Alan

[frederickbeard]

Its the hose. Get it fixed or replaced.

[kenikh]

I set the control initially at .9, then at .8 to see if altering peak had any effect. It blew right through to the moon, based on watching the gauge. I wasnt data logging at the time and will not be repeating the incident just to get data.

I had understood that double spring pressure is all a wastegate could hold, even with an EBC. Apparently that isn't the case, as I know I exceeded 1 BAR, more than double the .5 BAR spring.

Frustrated, as I've worked so hard to ensure the motor never sees this kind of abuse. Once is enough for me, so the car is grounded for the time being til we can figure it out.

[16Volt]

The WG isnt the hold factor in this equation, your EBC is.

[jpnovak]

Since you isolated the EBC you either have a problem with the feed line or the EBC itself. As others have mentioned focus your efforts here. It is not uncommon to see hose collapse under heat. Don't forget the hose also sees vacuum under closed throttle if you have it plumbed to the manifold under the throttle.

I don't think you described exactly how it is plumbed to your system.

btw, you made this comment.

Originally Posted by kenikh

If running EFI, it'll fuel cut to the injectors at a set MAP kpa.

IMHO, pull ignition first. If you pull timing you can reduce rpm and thus reduce exhaust pressure and then boost. It acts like a rev limiter. Yes, most EFI systems can set this limit based on pressure (or other variables)


Pulling fuel makes the engine go quickly lean under high heat generation. Bad things happen here as the sudden lean condition actually increases the chance for detonation. Keeping fuel continues to cool chamber when there is no spark to lessen.

Think about how knock sensors (or J&S Safegaurd) work - they don't usually affect fuel flow. same effect, different cause, same solution.

[TurboKraft]

Aren't you piggybacking a TEC on your CIS?
And that is what you're using for the boost control?

Consider using a non-GM valve. We gave up on those a long time ago, only success with these, and the default position in case of failure is open, so WG spring pressure only.

Plumbing:

[kenikh]

Here's what I see:



I don't see any notion of pulling timing for boost.

Another thing I need to confirm: Richard Clewett logged into the machine remotely and altered the tune a while back to work on the IACV config. Today, I was looking it over and the tuning app no longer recognized the MAP sensor configuration. I need to double check and see if the MAP is actually reporting accurately...which could very well be another culprit.

[kenikh]

Chris, I'll take one. Email in your inbox.

[16Volt]

.....i have a 3rd grade math level admittedly but isnt 210kpa around 30psi?