Overcoming 2LTE fuel cut limit

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Thanks for the explanation- my head is wrapping around this a little more now...
My boost controller allows me to spool up the turbo a little more (without added fuel) before my waste gate is actuated. However, since I maxed out at 12 psi stock, I only increased to about 14 psi so that I would not run into a fuel cutoff situation. What you are putting together eliminates the fuel cutoff at about 15 psi for my engine. But until I add an intercooler, my max should still maybe only be about 15 or 16 psi. I will read further and try to narrow that down a little.
Again, thanks for your knowledge and patience!
 

GTSSportCoupe

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@Lenny33 (and any other KZJ78 owner), I checked the drawings and it seems your ECU boost sensor is mounted on your intake manifold. This is the vacuum hose you need to cut to insert the bleed valve. And you definitely have a filter on your boost line as well (like the 2LTE). The filter is 23265 in the drawing below (just to the right of the red circle I drew).

Vacuum Hose2.jpg
 

GTSSportCoupe

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Thanks for the explanation- my head is wrapping around this a little more now...
My boost controller allows me to spool up the turbo a little more (without added fuel) before my waste gate is actuated. However, since I maxed out at 12 psi stock, I only increased to about 14 psi so that I would not run into a fuel cutoff situation. What you are putting together eliminates the fuel cutoff at about 15 psi for my engine. But until I add an intercooler, my max should still maybe only be about 15 or 16 psi. I will read further and try to narrow that down a little.
Again, thanks for your knowledge and patience!
You got it! And check out the picture I found for you above ^^. It shows where you will need to insert the bleed valve that I send you on your 1KZTE engine. You're right, you won't need it until you run more than 14psi.
 
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Thanks!
I should have mentioned - I know exactly where it is because I have recently put a boost sensor in right there and I have just replaced my MAP. I was just talking through it a little to make sure I had a good understanding of it all.
Thanks again!!
 

GTSSportCoupe

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Thanks!
I should have mentioned - I know exactly where it is because I have recently put a boost sensor in right there and I have just replaced my MAP. I was just talking through it a little to make sure I had a good understanding of it all.
Thanks again!!
I should note that in all my conversations above, when I talk about "boost sensor" I mean the ECU MAP (boost) sensor. Easy to confuse with a boost sensor for a boost gauge which I think is how you've been talking about it.
 
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I should note that in all my conversations above, when I talk about "boost sensor" I mean the ECU MAP (boost) sensor. Easy to confuse with a boost sensor for a boost gauge which I think is how you've been talking about it.
I smell what you are stepping in! Can be confusing, but I have been on the same page with you.
 

GTSSportCoupe

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Sorry for the delay guys; just an insane busy time of year right now for me. Anyhow, got 'em all put together. Here is what you'll get, and I've attached the pictures that show where you need to install them for a 2LTE or 1KZTE. The barbed 'T' is maybe a touch on the big size, so you'll have to work a bit to get the factory vacuum line onto it. The good news is the line won't pop off again at high boost, haha.

I've set them all to about 4 turns out. This is a good starting point. If you get the overboost check engine light, then adjust the valve out. If you find your engine is gutless and the boost compensation is not working, turn the valve in. 1/4 at a time is usually best, but you can fine adjust beyond that if you want.

You only need these if you're running more than 14-15 psi or so. Generally I only recommend running higher than that if you have an intercooler. The purpose of the bleed valve is to keep the ECU from going into fuel cut, while retaining a nice boost compensation fuel curve. For full tuning you'll also need a manual boost controller on your turbo (to turn up boost), and if you're intercooled, you'll benefit from turning up the spill control valve on the injection pump for more fuel. In fact on the 2LTE at least you'll have to turn up that spill valve to be able to hit the higher boost levels at all. The 2LTE really comes alive at 17psi and beyond! :)

I'm shipping out 4, and I've got 6 more if anyone else wants one....

IMG_20190912_084214673.jpg
IMG_20190912_084248888.jpg


2LTE Installation:




1KZTE Installation:
 

GTSSportCoupe

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Just a little hint for you guys when you receive these and start your tuning.

I've found that the 2LTE ECU starts to cut fuel even before it throws the CEL. So when you start tuning, find the valve position where you just barely avoid the CEL light. Then open it another 1/2 turn or so to get completely out of the fuel cut. From this point you can fine tune for best peak power. As my manual boost controller is completely closed (set for max possible turbo boost), I simply adjust the air bleed valve until I see maximum boost on my boost gauge. I look for the maximum boost when I'm on the highway under maximum load with the torque converter locked. Maximum boost is only achieved when the motor is getting maximum fuel. It takes more fuel to work the turbo hard enough to generate that extra boost pressure.
 
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Just installed. I realize that I am going to have to play with this controller and do a lot of fine-tuning, but at what psi do you believe you sent these out to cut off at?
 

GTSSportCoupe

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Just installed. I realize that I am going to have to play with this controller and do a lot of fine-tuning, but at what psi do you believe you sent these out to cut off at?
Very rough. All I can say is you're probably within one turn in either direction of where you should end up. In the final tweaking, even an 1/8 turn can make a pretty big difference.

What boost pressure are you shooting for at your intake manifold? I can give you some tuning ideas based on your goals.
 
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Interesting results so far - must be missing something...
With a manual boost controller I was set to max at 14 psi boost under load (staying right under fuel cutoff)
Yesterday I added my bleed valve. So in order, it goes manifold, filter, boost sensor for my gauge, bleed valve, MAP sensor. (Hard to see pic included).

I then began turning my boost controller for my waste gate slowly. 1/2 turn clockwise - nothing. Full turn - nothing. Then turned boost controller 2 full turns clockwise and boost never went up. I now seem to be maxing at about 12 or 13, which is down from where I was at before the bleed valve!
???
My understanding of the bleed valve was that it would bleed off pressure after my boost gauge sensor (so I could tell how much boost the manifold was actually seeing) and before it hit the MAP sensor so as not to hit fuel shut off pressure.
Was I understanding this incorrectly?
 
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