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[Invasion1]

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[LukeZ34]

I got my MBC from http://www.boostvalve.com and I've been satisfied with it so far. Easy to operate and a nice design. For $39 I decided to try it, and I know I won't be going back to the stock boost controller ever again.

Might not hurt to get yourself a A/F guage if you don't already have one. This way when you turn up the boost you can see where your limits of your fuel system are at. That's my next purchase along with a permanent boost gauge.

[dbtk2]

I also have a boostvalve, and it works great. I was very satisfied with it on my Lumina, but took it off because it had me worried for my tranny. (which was probably a good thing because the tranny started slipping a month or so later anyways) I have been thinking about investing in the upgrade kit for the 2 stage one because I want to be able to drive around with low boost (like 6lbs. or so) and then when someone deserves to get spanked, I can just switch it up to 12psi and show them not to mess with the Euro. It really looks like a nice setup. But anyways, the stock boost control is pretty crappy, and if you think your turbo spools fast now...holy hell, we're talking INSTANT spool with a mbc. I modified my stock boost controller on my STE to be adjustable and it made a huge difference as well, it still has a slight boost ramp because the computer is controlling it to a small extent, but you don't need the boost to come any sooner because it will still burn the tires off with no problem at any speed under 20 or so...

 

Shawn

[Guest TurboSedan]

i am using a grainger valve from M&M Racing for both my GTS and Cutty. it was only $25 and comes pre-drilled with the vent hole. it's very easy to use and adjust. i haven't really used it on the Cutty yet, but it works GREAT on my GTS. i like it so much i wouldn't consider any other form of boost control. on both cars, i simply have the g-valve mounted inline on vacuum line between the turbo compressor outlet to the wastegate can. if you don't have a fitting on turbo compressor outlet, then you can source it from a manifold vacuum source. the turbo on my Cutty has a fitting on the compressor outlet, but i used to have a TGP turbo with no fitting there. if that's the case with your turbo you could always source the g-valve from the plenum....right behind the throttle body where the automatic transmission line previously went to would be ideal.

 

one thing i don't like about that boostvalve pictured above is that it is 'T' shaped. i believe when i seen that valve on Luke's TGP last March it had actually broken right there and was somehow fixed....maybe i'm wrong. the M&M Racing valve however is completely inline:

 

 

a grainger valve (like the boostvalve mentioned above) will give you full boost instantly becuase it will stay shut until a preset pressure. so the wastegate will be completely shut until say 10psi (whatever you have it set to) and at 10psi the g-valve pops open and allows the wastegate to open fully. it's a pretty simple device; it just has a ball and spring inside it with a vent hole on one end. you adjust it by tightening it, and it has a lock ring on it so it won't turn by itself and mess up your boost setting.

 

a two stage boost control would be really nice, ecspecially with the 5-speed since 1st gear is so damn STEEP. i would probably go for low boost (vacuum line straight to manifold source) and the other to a grainger valve set wherever you want it. probably go for low boost through 1st gear and part of 2nd, then hit the switch 8)

[LukeZ34]

You won't regret it.

 

In answer to your question above.. Yes, I do run w/ it in all the time. It's set at about 5-7 PSI right now. Shawn's right, the turbo spools FAST w/ this thing installed. It's hard to keep control of this car sometimes.

 

Here's some pics of my install, just incase your curious.

 

 

[Guest TurboSedan]

Might not hurt to get yourself a A/F guage if you don't already have one. This way when you turn up the boost you can see where your limits of your fuel system are at. That's my next purchase along with a permanent boost gauge.

 

a boost gauge is a MUST when adjusting a grainger valve. i suppose you could just adjust it up to BFC and then back it off half a turn (been there done that), but it's not a good idea. sounds like you have gauges taken care of though fwiw i am NOT happy with Autometer's mechanical boost gauges. i plan on an electronic boost gauge for the Cutlass. i have an Autometer A/F gauge in my GTS too, and it's nice seeing full rich whenever i go to WOT (was off scale rich on the dyno with WB02 monitoring as well). still, i would much rather have an EGT or WB02 for the Cutlass than a narrow band A/F.

[LukeZ34]

Yea, first gear is a bitch. But second makes up for it by pinning you to your seat.

 

I'm digging around eBay right now for some gauges. I'm really curious to see if the WBO2 readings I was getting at the Dyno were accurate. The car is taking a road trip to the track in a couple of weeks. I'd like to have some safeguards in place so I can play around with that MBC some.

[Guest TurboSedan]

I was very satisfied with it on my Lumina, but took it off because it had me worried for my tranny.

Shawn

 

why take it off when it's adjustable? no gauges? worried about boost-ramp? (non-existant with a g-valve lol). heck, come to think of it i don't think i'd want to use a g-valve MBC with an automatic. i just don't trust the 4T60 enough.

[skalor]

You can make a MBC exactly like the ones pictures with parts from grainger for about $15. I made one for my friend and it looks identical to the one TurboSedan posted above.

[dbtk2]

I was very satisfied with it on my Lumina, but took it off because it had me worried for my tranny.

Shawn

 

why take it off when it's adjustable? no gauges? worried about boost-ramp? (non-existant with a g-valve lol). heck, come to think of it i don't think i'd want to use a g-valve MBC with an automatic. i just don't trust the 4T60 enough.

 

It was definately the boost ramp I decided would be a good idea to have. If I turned a corner at ~25mph, and went WOT as I came out of the corner the tires would go up in smoke. Now, while my friends thought this was cool, I didn't think so much of it.

 

I am thinking about putting my modified stock boost controller from my STE on the Lumina, so I can raise the boost a little, and make the boost ramp a little quicker without totally destroying my tranny. If someone wants a mbc for these cars for cheap, you can make one for the cost of a screw (~$.05) if you really want...

 

Shawn

[Jeff M]

Just to wrap up the main points so people reading here today even if not posting in this Topic, and to those that come back later, maybe even do a search a week. month, year from now, here are some of what has already been said/is known and what is left that must be mentioned so that people can make informed decisions about a MBC.

 

Pros:

Faster boost ramp-up

Snappier feeling of power during instant boosting with manual control

Dual stage to keep the boost at lower/nicer settings for daily driving and higher for when the need arises 8)

Potentially faster et’s if there is traction to keep the power to the ground

With traction, ability to better smoke the competition instead of their tires

 

 

Cons:

Defeating ECM Program Safety Settings when dealing with engine knock/detonation

Slower et’s if owner has limited traction i.e. old tires etc, or hard time backing off throttle with adrenaline pumping

Harder on tranny components, mainly clutches

Too much one-wheel burnouts will lead to differential failure

Too much boost at low rpms will put turbo into surge and over-boost condition

 

 

Since I am trying to still do the work I need to here at my shop, and at home and for others, and since my wife and I are scheduled with surgeries this week, I do not have time to be working on my computer posting, emails and such so will answer questions ahead of time for those that might ask.

 

“Defeating ECM Program Safety Settings†is in reference to the settings in our chips (mine included) that if knock retard is sustained at any value above 2.3 degrees for longer than a set time period, boost will be reduced in an attempt to save the engine. Manual control defeats this backup safety feature.

 

“One-wheel burnouts†cause the differential to side load and will eventually wear to the point that straight-line accelerations will no longer be power by both wheels (that dual-wheel burn-out pic on my chip page where I indicated “who needs an LSDâ€Â). I hope no one has an idea of what I am talking about but one TGP owner here in my area that did too many one-wheel burn-outs was starting to complain about his car being slower and his tires always spinning, come to find out he only had one tire spinning, the other was not, and with the power these cars have in first gear that can spin both front tires with ease, only having one tire sending down the power made for a car that ran like it was in the rain all the time. Also when only one tire is spinning (going around a corner, or all the time once the differential is messed up), the differential is now turning twice as fast as the speedo shows.

 

“Too much boost at lower rpms†will cause this turbo to go into a surge condition, heard this more so with the manual guys when shifting into higher gears 3rd/4th/5th and WOT, but auto’s can do this as well, especially ones that are not running proper (had one here that would not always downshift with WOT and when it stayed in the higher gear the rpms were very low and surge was nasty, and boost spike hit the boost fuel cut thankfully). Surge is very hard on the bearings in the turbo. Also there is the potential for boost that appears low enough for safe running on 92 octane to be way more than can be handled with 92 octane, that with the fact that these engine’s peak VE values run at low to mid rpms with these long runner intakes, and that our turbos spool very fast, air flow will fill the combustion chamber way more than most expect when they use the boost gauge as an indicator of safe settings.

 

So, a good share of posters here know most if not all these pros and cons , and will run data loggers to check themselves, and restrain from beating on and getting carried away and all that (just like dbtk2 just said) 8) , we got lots of smart owners here so don’t freak from my post :oops: , I just feel its my duty to others that read here now and later that are not as avid as you guys posting, to have the facts up front so they can also make an informed decision on their investment .

 

Jeff M

[LukeZ34]

 

“Too much boost at lower rpms” will cause this turbo to go into a surge condition, heard this more so with the manual guys when shifting into higher gears 3rd/4th/5th and WOT, but auto’s can do this as well, especially ones that are not running proper (had one here that would not always downshift with WOT and when it stayed in the higher gear the rpms were very low and surge was nasty, and boost spike hit the boost fuel cut thankfully). Surge is very hard on the bearings in the turbo. Also there is the potential for boost that appears low enough for safe running on 92 octane to be way more than can be handled with 92 octane, that with the fact that these engine’s peak VE values run at low to mid rpms with these long runner intakes, and that our turbos spool very fast, air flow will fill the combustion chamber way more than most expect when they use the boost gauge as an indicator of safe settings.

 

Jeff M

 

Thats what that is! What would need to be changed in the ECM to eliminate that? It does it with both boost controllers (stock & MBC). Though, it never did that when I was up in colorado this past march, but once I got back in to KS, it started doing it again. Must have been something with the thinner air.

[skalor]

Yeah, my turbo surges if I try to floor it lower than ~3000 rpms in 3rd, 4th, or 5th. I'm fine if I'm above 3000 rpms, or at any rpm in 1st and 2nd. I thought it was just missing at first, but I replaced plugs(good #8s), wires(Taylor), and coils(stock GM). I came to realize that our turbo is way too small and it was surging from such a high load on the engine. Something that doesn't happen with autos because they shift to a lower gear. I haven't found a cure yet except for a bigger turbine housing. Maybe someone else can chime in on what would help.

[Guest TurboSedan]

skalor, when you got a grainger valve directly from Grainger, did you have to drill the hole in it? i bought mine from M&M Racing because it was already modified (drilled). and $25 is cheap anyways

[Guest TurboSedan]

 

Too much one-wheel burnouts will lead to differential failure

 

“One-wheel burnouts†cause the differential to side load and will eventually wear to the point that straight-line accelerations will no longer be power by both wheels (that dual-wheel burn-out pic on my chip page where I indicated “who needs an LSDâ€Â). I hope no one has an idea of what I am talking about but one TGP owner here in my area that did too many one-wheel burn-outs was starting to complain about his car being slower and his tires always spinning, come to find out he only had one tire spinning, the other was not, and with the power these cars have in first gear that can spin both front tires with ease, only having one tire sending down the power made for a car that ran like it was in the rain all the time. Also when only one tire is spinning (going around a corner, or all the time once the differential is messed up), the differential is now turning twice as fast as the speedo shows.

 

Jeff M

 

i wouldn't consider one wheel burnouts to be a CON from using a MBC. doing a burnout around a corner has nothing to do with what type of boost controller you are using. no one should be doing that period.

[skalor]

Yeah, I drilled a .060"(IIRC) hole near the knurled section. That way it wouldn't be able to get covered up. He hasn't had a problem with it getting plugged so I guess it was big enough. 8)

[Guest TurboSedan]

cool. every once in awhile i remove my g-valve and disassemble it and clean it with rubbing alcohol. hasn't plugged up yet but they can get dirty.

[dbtk2]

My turbo would surge from time to time on my STE as well. (didn't do it until after the topend...maybe I'm flowing too much air now???) If I got on it at like just a little over 30 so it wouldn't downshift to 1st it would do it pretty bad. And when I didn't have my tv cable hooked up right after the topend swap it was really bad. In 3rd from like 30mph it was HORRIBLE...I thought it was just the fuel/timing management, I didn't know it was the turbo surging... Learn something new everyday!

 

Shawn

[Jeff M]

Luke, skalor, dbtk2, I have yet to work on a manual but hope I can offer some help based on similarities in the tests I ran on a few dozen auto TGPs and TSTEs. Changes to the chip will need to be made, this is getting easier for some now so good luck with it!! As I looked at the manual chip that was going around a while back, besides the TopGun entries, there were increases in boost above my settings at low to mid RPMs and low to high TPS, those values need to be put back down :!: I know it “feels†faster or snappier when you have small amount of TPS and RPMs increasing the power/boost a lot, but aside from the issues this is causing with the stock turbo, the idea of the boost table is to run boost based on the driver’s input from the throttle, so that small inputs are commands for small amounts of boost and acceleration, if the driver needs to go faster/have more boost then the throttle goes down/higher TPS. I look at the 6x6 boost table as something you want to work with from an applied sense, small throttle inputs; small values in boost at any rpm, increasing throttle then increasing boost. Then looking at rpms and from what I found as well as what you manual guys are finding at the lower rpm values is the need for less boost all together at the first table line/2,400 rpms, especially at or near 100% TPS, sloping this up fairly quick (too much and interpolation of the table will make the lower needed values at 2,400 less effective) so that by the 3rd rpm line you have max boost at WOT TPS. You still need to ramp up lesser TPS input values at this higher rpm tables lines, so that is looks like a nice jagged saw tooth sign wave, not a nearly flat saw tooth wave. This will take some playing, I know it will help, but if you find the boost is still wanting to fly up too fast (or not fast enough) there is also a Boost Initialization table that controls the ramp up towards the boost table setpoints, kind of an anticipator, but more so part of the Integral Gain in a PID control system (if I remember that correctly, been a while since I had to work on PIDs). There is also a Derivative Setting but that one is very touchy and the Integral one should work for you well enough.

 

Good luck guys , hope to hear positive replies after you make these changes, maybe toss out between each other what seemed to work, though you might find what's perfect for one is only good for another, tweaking is always needed but baseline values are a good starting point for all 8) .

 

Might be a while before I can answer any other questions, very tight and intense week for me.

 

Jeff M

[skalor]

I'm working off of a modified TopGun160, which I bought from you.

 

Anyways, I was playing around with 'desired boost pressure base'(PRM vs. TPS vs. kPa)table a little before one of my shift cables broke. I figured with more tweaking of the table that I would be able to control the boost more to avoid a surge condition. I just didn't know if it would outflow the wastegate at those rpms with such a high load on the engine.

 

I sometimes do tuning/programing with servo/stepper motor controllers and I was actually starting to look to see how similar the wastegate controller was to what I normally work on. It's kind of like a low interia motor in that it can ramp very fast, but it acts like a high interia motor in that it will overshoot the desired level very easily. That's the way I think of it, but I could be wrong as I'm still pretty early in the learning curve for this kind of stuff.

[Jeff M]

I'm working off of a modified TopGun160, which I bought from you.

 

I like hearing that 8) But this makes me think your direct drive(n) gears are very prone to high boost at lower rpms, and thinking about that, I can't imagine how bad it must be for the other ones I mentioned :shock: Depending on what time you got that chip, the Boost Ini Tables (read below) might be a little more aggresive that later versions, that since I was hearing too often tire roasting take-offs, which are impressive but provide slower et's, and is hard on the tranny.

 

Anyways, I was playing around with 'desired boost pressure base'(PRM vs. TPS vs. kPa)table a little before one of my shift cables broke. I figured with more tweaking of the table that I would be able to control the boost more to avoid a surge condition. I just didn't know if it would outflow the wastegate at those rpms with such a high load on the engine.

 

Sorry about the cable, hope that is fixed. As stated above and in more detail below, try the Boost Ini tables. I don't think we have a problem with the wastegate, never had boost creep ever, even had to force it closed by other means to get more than 12 psi (and 100 octane).

 

I sometimes do tuning/programing with servo/stepper motor controllers and I was actually starting to look to see how similar the wastegate controller was to what I normally work on. It's kind of like a low interia motor in that it can ramp very fast, but it acts like a high interia motor in that it will overshoot the desired level very easily. That's the way I think of it, but I could be wrong as I'm still pretty early in the learning curve for this kind of stuff.

 

Ahhh, sweet, then you have an pretty good idea 8) The below might help expand that understanding, and has some tuning tips to try as well.

 

Some think of the components of PID this way; where P/Proportional is shown to affect system control stiffness, and I/Integral affects accuracy, and D/Derivative affects stability. Others go with P as Gain, I as Reset and D as Rate. Another way if I am remembering correctly is P is the primary rate of change, I is how fast the changes is allowed to be made and D is the kick in the ass if neither is getting the job done. So if boost is 1 psi and we want boost to be 2 psi then P can make a change pretty easy if it’s a small number, but if we want to shoot from 1 psi to 10 psi, then P by itself will not make it so D allows it to jump its change rate to achieve 10psi, but neither will work after the change is attempted and I is needed to smooth out the surges of the controller basically chasing its tail; oops I was 1psi and want 10psi but now got 12 psi, back it off, shit got 8 psi, try again, damn, 12 psi again.

 

So, the Boost Table Value Set-points are what we are shooting for first, though keep in mind the next table will help as well. Then Initialization Table Values are how fast we can shoot for them/boost set-points, and another lone value allows spikes and bumps to be ironed out but it’s pretty good where it stands. So aside from the boost table values being changed to something you want to shoot for, see what the ramp up is like after those changes and use the Initialization table to adjust how quickly or slowly boost meets its set-points.

 

Jeff M

[Guest TurboSedan]

But this makes me think your direct drive(n) gears are very prone to high boost at lower rpms, and thinking about that, I can't imagine how bad it must be for the other ones I mentioned :shock:

Jeff M

 

i have to admit i've never even considered this problem! i guess i'll be keeping my ears wide open for compressor surge. i never have driven my Turbo Cutty yet, but it should be done this week or next (getting excited, i haven't driven this car since last Sempember when it was NA). i do have a couple different TGP wastegate solenoids sitting in the garage, and i'm using a TGP wiring harness so if the MBC doesn't work out at least i can plug this sucker in and use ECM controlled wastegate instead. my TGP chip has been modified for use with 5-speed but that's all i know about it (it's from god910). i don't even know where BFC is set.

 

all this chip talk is wayyyy over my head i wish i could buy a PC/PP2 and start using GMPCM software so i could at least look around and learn more about it.

[LukeZ34]

all this chip talk is wayyyy over my head i wish i could buy a PC/PP2 and start using GMPCM software so i could at least look around and learn more about it.

 

You and me both buddy.. It's been killing me hearing all this tuning talk and knowing we could get more out of these cars. I'm wishing I could afford the hardware to work with the chips too, but what money we have has to go to more important things.

[Guest TurboSedan]

what scares me most about getting started is that i don't even know how to use a PC. i never have used anything but a Mac! i've been planning on buying a laptop off ebay when i can afford it, but most all of my money is spent before i even get a paycheck

 

i do have a new Mastach ALDL cable and a CDROM full of datalogging software, but that's about it so far. i plan on buying a chip reader/burner and PC hopefully by the end of this summer.....before i do any more mods to the Turbo Cutlass anyway. my brother wants to go in halves on WBO2, at least that will bring the cost down.

[god910]

For those of you that want a high/low setup Sunshine is setup w/ an aircraft arming switch. Low setting disables the signal to the w/g, and "high" setting just gives control back to the chip. So, if you REALLY wanted a different setting you could change your w/g spring, if not, and 4 psi is good enough, use this and retain chip control during "normal driving" (if that even exists in a TGP 8) ). (I used it to keep my BOV quite, and control 1st gear, then switch to high)

 

The way I was going to set it up was a momentary switch, always on "high" then when depressed it went to "low" So you just hold it down during a launch, and only have to release it to get back into "high boost"

You could even mount it to the shifter (or one of those middle button N20 shifters)

Keep that in mind if you so choose.