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Discussion Starter #81
it may cause that. But I'm looking at 140mm^3 IQ. I think its too much? Maybe I'm wrong. But do you want to lower it also ? like to 110mm^3 or 120?
With my old setup (GT1756 / [email protected] bar / 2.25 bar turbo pressure) I was driving for almost a year. Here is my 4th gear run:

But with GTB2060 we started from 115IQ, then 120IQ and so on. There was improvement after every version until 140IQ. On low gears it pulls very very good, but high speed run seems to remain same.
My current tune version has a 140IQ but without any visible smoke. Low end torque is brilliant. But that's it.

I can lower fuel quantity, but I will lose low end torque. Fix me if I'am wrong.

You need to compare it with full logs from 1500 to 4500rpm.
Backpressure can kill so much power.

My car with only 1,7 bar and 90mm3 drive 80 to 160 in 9-10sec on speedo.

I test it with 2,0 Bar and 95mm3 and it was not faster, because of my restricted exhaust.
I have all logs, but they look almost identical to me. Can you explain to me where to watch exactly?

Your car is almost 400kg lighter if I'am not wrong. Hard to compare these numbers.

In my case I think exhaust is not a case. Maybe turbo manifold is too restrictive. Or butterfly valve with stock intercooler pipe (52mm diameter)...

Anyway, thanks guys for help. I'am starting to lose hope to reach this build main target :-/
 

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Discussion Starter #83
Hmm, just tried to do some logging without front bumper. Lowered fuel quantity to 125mm3. Boost to 2.35bar. And almost no difference with or without bumper... Maybe 1-2% VNT difference. So, it's definitely not a air flow issue before turbo.

I think, most likely I have problem with very restrictive stock elbow from intercooler till butterfly valve. Inner diameter is about 48cm. But what to do with butterfly valve? Delete it or just change it to butterfly valve with normal hose connector from Opel?
934637
 

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What if he has diesel runaway ?

Put one on the entry of the airbox that shuts off with the ignition and stays off until the engine is started again, thats what I m gonna do.
 

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You are totally right about it. I'm carrying a knife all the time. That can cut silicone hoses very easily. İf something happens. I will cut hoses and let the pressure out.
 

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Discussion Starter #92
Someone already discovered, that this valve only closes on engine shut off procedure and low RPM. When run away in progress this valve will not help at all. It is only for smooth engine shut off without any shaking.

Some news. I didn't planned to swap manifolds but someone offered to me dirt cheap Euro 3 16V intake manifold from GT. It's already in my trunk. Tomorrow I will send it to machine shop to cut out all EGR things inside manifold. And they will build adapter to silicone hose.

I think it will flow even better than my new type plastic manifold.
 

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Someone already discovered, that this valve only closes on engine shut off procedure and low RPM. When run away in progress this valve will not help at all.
Yeah, I realise that, which is why I was gonna remove mine and replace it woith one at the begining of the intake before the air filter, thats permanently closed with ignition off, that will help with runaway. :)
 

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Yeah, I realise that, which is why I was gonna remove mine and replace it with one at the beginning of the intake before the air filter, that's permanently closed with ignition off, that will help with runaway. :)
When my car was in paintJob. İnsurance gave me Fiat Egea 1.3JTDM. When I saw the engine. There was two valve. One is in front of the Turbo. One is front of the Intake Manifold
 

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Discussion Starter #98
First things first - log after butterfly valve delete.

This one was test version with lower VNT values across all map. Now that is what I want to see. Target boost 3350. It even started to overboost slightly. Hard job is done, time to play with computer :D

Back to the story. The original plan was to fit early type intake manifold without flaps. But just before disassembly I found out, that my late type plastic manifold has a bigger intake diameter than early type. And even on top of that, it doesn't have those strange EGR shapes, which can and will interfere air flow. There is A LOT of work to properly enlarge intake diameter on early type. So I abandoned plan A. This manifold will be fitted to my girlfriends Fiat Bravo 1.9 JTDm 16V, because of swirl flaps delete. Win win.

So, I removed metal part of late type manifold and test fitted 60mm inner diameter flange. There is a little bit extra material which you can cut to smoothen air flow. But don't go crazy.


Then I welded in 90 degree bend, and joined two pipes with silicon hose. Welds are not very pretty, but I am starting to learn how to weld properly.


After some tinkering with battery tray and cooling hose job was done. And it looks not bad.


There is one downside of removing butterfly valve. Sometimes engine shut off feels a little bit shaky, but nothing to worry about.
 

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That's it's main job...and the reason it's often called an anti-shudder valve. It's other tasks (for those that don't know) are to stop air flow in the event of the engine running on (burning it's own oil and revving to death...and the reason I won't remove mine) and partially closing occasionally to cause a little vacuum when the egr is open to help suck the gases through.
 

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Discussion Starter #100
Dude, read my last replay. This valve will not stop diesel runaway. It only closes on low RPM to smoothly cut out engine. When runaway in progress (high RPM) ECU will not close valve until RPM drops.
 
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