Overcoming 2LTE fuel cut limit

GTSSportCoupe

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Well, pradocruzer is the man. I finally took a minute to look for the original speed controller on the princess auto website, and what you do you know; they still have them!! This is the one: 8.5 CFM Pneumatic Speed Controller | Princess Auto

Price is right! Looks like there are a couple instore for $5 each. I'm going to go buy them today. Not sure if they ship to other countries for you other folks in the US, NZ etc. If they don't, I can order a bunch and mail them out....
 

GTSSportCoupe

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Just picked up one of those speed controllers. It's definitely the right thing. If anyone is interested in them let me know. They are normally around $150each through other avenues, but through this store they're $5 each. I just checked shipping and it's $7 for 10 of them shipped to my house. I could forward them on to anyone who wants one. Note you will need barbed fittings to connect them to vacuum line.

As said, in all my experimentation so far, these are the best option, and you can't beat the price.
 
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I just ordered a couple of each of the diodes to try out, but if you are doing an order of these put me down for one and id be keen to have a few options to try out, will just need it shipped to NZ though if you are happy to sort that.

Once your doing the orders pm me your payment details and ill get it all sorted.
 

GTSSportCoupe

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I just ordered a couple of each of the diodes to try out, but if you are doing an order of these put me down for one and id be keen to have a few options to try out, will just need it shipped to NZ though if you are happy to sort that.

Once your doing the orders pm me your payment details and ill get it all sorted.
Sounds good; I'll add you to the list! And no prob, I don't mind mailing to NZ.
 

GTSSportCoupe

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I just placed an order for 10 of those air speed controllers. Once I receive them I'll forward them to anyone who is interested. Got two people interested so far.... Let me know if anyone else wants one. It'll cost you $6.30CAD plus whatever it costs me to ship to you. I'll ship using Canada post (cheapest). If you guys are interested, I can make these into a bit of a kit with the proper NPT fittings, some vacuum hose and a vacuum 'T' to connect to your boost line. Again, I'll just pass the costs on; whatever they end up being.
 

FJBen

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I received the 10 air speed controllers. Let me know if anyone else is interested....
So dumb question, what is the difference between this and a manual boost controller?

Are you running this along with your manual boost controller?
 

GTSSportCoupe

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So dumb question, what is the difference between this and a manual boost controller?

Are you running this along with your manual boost controller?
Not a dumb question. The manual boost controller is used to control when the waste gate on the turbo opens. At a certain adjustable pressure the internal ball/spring is overcome (opens), pressure gets through and opens the waste gate actuator.

The air speed controller is basically a highly adjustable 'air leak' for lack of better term. It is 't-ed' in right before the boost sensor, and is constantly leaking a controlled amount of air such that the pressure seen at the boost sensor is proportionally less than what is in the intake manifold. So for example, my intake manifold will see between 0-19psi of pressure. However, the boost sensor will see the same boost curve shape, but only 0-14psi of pressure.

This reminds me, there are other products on the market called 'fuel cut defenders'. These give an abrupt pressure cut-off at a given adjustable pressure. It would work much the same as the zener diode does (as discussed above). The problem with the Zener and the FCD's, is that as turbo boost continues to rise beyond the 14psi, there is no more fuel compensation happening, as the ECU doesn't think anything is changing.
 

FJBen

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Not a dumb question. The manual boost controller is used to control when the waste gate on the turbo opens. At a certain adjustable pressure the internal ball/spring is overcome (opens), pressure gets through and opens the waste gate actuator.

The air speed controller is basically a highly adjustable 'air leak' for lack of better term. It is 't-ed' in right before the boost sensor, and is constantly leaking a controlled amount of air such that the pressure seen at the boost sensor is proportionally less than what is in the intake manifold. So for example, my intake manifold will see between 0-19psi of pressure. However, the boost sensor will see the same boost curve shape, but only 0-14psi of pressure.

This reminds me, there are other products on the market called 'fuel cut defenders'. These give an abrupt pressure cut-off at a given adjustable pressure. It would work much the same as the zener diode does (as discussed above). The problem with the Zener and the FCD's, is that as turbo boost continues to rise beyond the 14psi, there is no more fuel compensation happening, as the ECU doesn't think anything is changing.
Got it. A little bit of foolery. For awhile people were doing a mod on the VW TDI's to fool the throttle position sensor to dump more fuel.
 
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So to make sure my newb mind understands, this device will prevent a sudden fuel cut by reducing the pressure that the map sees?

Thanks for always helping beginners like me and for sharing your knowledge.

I would like one, please.
 

GTSSportCoupe

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Can all you guys who want one of these air controllers please PM me your mailing address? (I turned my PM's back on...sorry about that). I think I received one address so far.....

I'm going to buy a bunch of fittings for these too, and will make a little drawing to include (showing how mine is successfully setup).

Cheers,
Nick
 

GTSSportCoupe

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Hey Guys, I'm sorry for the delay. Busy with the start of school etc. Anyhow, I just ordered fittings for the flow controllers from Mcmaster carr. A barbed fitting for vacuum hose on one side, and a little air filter for the other. I also ordered barbed Tee's for the vacuum hose. Will pickup some vacuum hose also. This way you get a kit that is ready to go. I'll try to pre-set the flow valve too, so at least you're in a good starting spot. I bought enough that I have 10 sets available. Will try to ship out later this week to those who have already indicated interest. Have 6 more up for grabs if anyone else wants. So far cost for all the parts is at about $15 per kit. Not sure how much shipping will be, but will go for the cheapest Canada Post option.
 
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GTSSportCoupe

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Hey All. Well I felt I could not ship all these out unless I tried the new pieces to make sure they all worked. Threw them onto my truck this morning and they worked perfectly. So now I just have to assemble and ship. Hopefully in the next two days.

So you'll get the bleed valve, filter on one side, barbed fitting on the other, vacuum hose and a barbed vacuum T. All you do is cut the vacuum line between the boost hose filter and boost sensor, and fit in the barbed T.

Here are some pictures from this morning:

IMG_20190910_081806227_HDR.jpg


IMG_20190910_082000687.jpg


IMG_20190910_082018894.jpg



For those with the 2LTE, this is where you will insert the air bleed valve 'T' fitting.

644510a3b0195cb1bf742e76aec6f8d1.jpg
 
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Thanks again for doing all of this - very nice of you.
To make sure I understand:
So since this will fit in AFTER my boost sensor, my gauge will still read correct boost that the turbo is producing, right? This avoids the MAP sensing too much pressure and causing a fuel cut. So then my manual boost controller can be adjusted for more boost. How much boost do you feel is a sweet spot without working a stock turbo too hard?
 

GTSSportCoupe

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Thanks again for doing all of this - very nice of you.
To make sure I understand:
So since this will fit in AFTER my boost sensor, my gauge will still read correct boost that the turbo is producing, right? This avoids the MAP sensing too much pressure and causing a fuel cut. So then my manual boost controller can be adjusted for more boost. How much boost do you feel is a sweet spot without working a stock turbo too hard?
If you're measuring boost at the manifold, your boost gauge will see exactly the pressure that your engine is getting.

The ECU boost sensor is separated from the manifold by a little filter (on the 2LTE anyhow, I'll have to look at the 1KZTE drawing to confirm for your motor). That filter gives enough restriction it allows a pressure drop caused by the air control valve leaking air. This is what makes the ECU boost sensor see less pressure.

Regarding maximum boost, I'm not personally familiar with the 1KZTE. The CT12B turbo (1KZTE) does have a smaller shaft diameter than the CT20A turbo (2LTE), and is thus a bit weaker. Personally I probably would not push it past about 17-18psi. But you can do some research into it and see what you find. Also, if you don't have an intercooler, you don't want to go too high as the intake air temperatures will be much hotter. So maybe with no intercooler only tune for 14-16psi or so? Again, maybe ask some of the guys who have tuned up 1KZTE motors to see what they're doing.

Anyhow, no matter what you do, if you're going over 14psi, you'll need a solution like this bleed valve.
 
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