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Discussion Starter #1
Ok, I would like to know what kind of settings others are running for boost control

I installed mine today. I have a 10psi wastegate spring (44mm tial) Sp67 turbo. I set target boost for 16 psi. Boost comes on goes to 12psidrops to 10psi holds then slowly builds to 15 at upper end of rpms?
 

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slowly giving up...
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i can't check mine now, but i played around with it a bit, and got rock solid 15psi immediatly, and it bled off perfectly. no problems here.

(i can't check because there's no battery in the car, and it's mostly taken apart. :()

-shaeff
 

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I still need to get mine situated as well. I had it set to 10psi, but the solenoid was too far from the turbo and was spiking to 11-13 and I'd hit FC. I moved the solenoid closer and took out a lot of vac. line, but it still spikes (not near as bad) to 11-13. I re-set it to hold 8.5psi, but it still manages to spike... What is reccomended for length of the vac. lines to and from? I have my solenoid on a bracket off the right strut tower and down beside the compressor housing. If I had to guess I'd say the lines are maybe 6-8". Maybe some settings are wrong. Dunno
 

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Discussion Starter #5
I would say settings.

I got mine working alot better
this helped alot. Instructions that come with the selonoid need to be changed if you ask me
Originally Posted by -Rich87Tx2
I wrote this a while back. You might find some of it useful. It may be for ver. 4.4. I don't remember for sure.
-Rich

************************************************** ***
The MAFT-PRO boost control is pretty easy to use. It's almost the same as the AVC-r. The 'problem' (for me) was that the start duty default was too low, like 20% and my actuator was too loose. I tightened the actuator to 13psi without the MAFTPRO. When the start duty was 20% (low), nothing seemed to work as described. I brought that up to 60-80% and everything started to work as the book described.

Based on what I know about the AVC-r and the MAFTPRO, I'll toss the following intot he mix and see what turns up:

What the MAFTPRO manual should say about boost control is set your actuator to the minimum boost you want to run WITHOUT MAFTPRO correction. Then set your target PSI to what you want (19psi), set Start PSI to 3 psi less than that (16psi), set start duty to 50%, set your TPS and RPM to slightly above normal cruise, set your gain to "10".

****This means you will build boost quick on the bottom (until Start PSI is met), but the actuator will start opening too soon, and too quickly. <- safe

Do a third gear pull and log your boost. The line for solenoid will spike when the turbo is trying to build boost (100% solenoid duty). AFTER THAT - If the line goes up raise your start duty. If the line goes down, lower your duty. Try to get a line that starts out fairly level. If you boost goes to target and then drops raise start duty. If you boost spikes, lower start duty.

****Adjusting start duty adjusts the amount of air getting to the solenoid/actuator *initially*. The gain controls how quick the solenoid can self adjust thereafter. For now, you want to adjust this percentage to get a level line after the spike.

Once the solenoid line is fairly level after the spike, raise the Start PSI until you get a little boost spike. Lower it a bit to remove the boost spike.

****Similar to the above. On a large, laggy turbo you can build boost fast, then slam the actuator with alot of air at the last minute to avoid a boost spike (High Start PSI, low start duty). Alternatively, you can apply less air initally but apply it earlier to prevent boost spike (low Start PSI, High start duty). It may be desireable to do the latter to take the edge off a really hard hitting turbo.

Lower your gain to ~4 and hopefully you'll enjoy stable boost.

**** Lower the gain to ~4 and make sure your boost stays stable. If the gain is too high, boost can fluctuate. If it's too low, boost may creep up/down.

That's my take on the AVC-r / MAFTPRO boost control. Comments welcome....
 

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Thanks. I've seen that before but couldn't find it. I'll see if it helps. Only bad part is me not having a laptop to log/tune with.

EDIT: I went out and looked over my settings and the TPS spool was way too high. Also the Start DC is set at 45. It was at 50 initially, but still crept up a bit so I turned it down. Went for a short drive and could do WOT in 1st, 2nd and 3rd with no FC. :) AFR's were ~10-11.5:1. AFR tracking is set to 11.5 and I haven't messed w/fuel much yet. High load from ~3300-5800 I pulled 2%. Waiting for laptop to do more than one thing at a time. :p
 

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Well, I changed a few things and FC is less of an issue, but is still there. Maybe more so when it's cooler outside. One of my problems was TPS spool was at 2.5. I moved it to .74 and it helped a lot. Another one is DC start %.. I've read that the initial "20" was too low and 70-80 worked better for one person. Tried that area. Read an above post and tried around 40-50. Little better, but still spikes. I tried the initial setting of "20" and did a 3rd gear pull and it spiked/crept past my PSI set of 8.5 to ~11 and hit FC.

Here's my settings ATM:

TPS Spool .74
RPM Spool 2496
TPS Start 2.5
PSI Start 4.4
DC Start 20
PSI Set 8.2
PSI Aux 8.4
Gain 8.4
DC Set Aux 45.2

It will usually go to ~10psi. My guess is that w/my mods (no WG shims) that is the base boost now. If I could get a rock solid 10lbs I'd be happy, but once it goes past it'll hit FC. I "should" be using a laptop this weekend and hopefully can get it dialed in that way. Other than that I've been adjusting PSI start and DC start % to alleviate boost spikes/creep. One time where it almost always hits is a good downshift and then WOT or 3rd gear @60 MPH then punch it. I "think" colder air makes a difference too. My MT is usually around 90-110* while driving.
 
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