WJM Posted December 5, 2003 Share Posted December 5, 2003 Skip: we went out, and the RX didnt seem to hit anything, jsut run out of breath around 6k. He was running 12psi. We did a few long pulls. Now, there was a little big of a hop/skip type of surge....but just a tad. Then we went out in the GL-10...and it's hop/skip surge was 4 times worse that the RX. But I was running stock boost. My RX...it boost bleeds after 4k. It'll run up to 10psi and stop, I *think* i only got fuel cut once...but it was notihng like you describe. After that first time it hit 10psi, it never did anytihn gout of the ordinary again. Just pulled like crazy at 10psi. I did several long pulls, and raced some mercades sedan on the interstate. A LONG 5th gear pull there...got to 125~130 or so, I had to let off a few times to let him catch up...then lay into it again to stay in front. Quote Link to comment Share on other sites More sharing options...
Warp3 Posted December 5, 2003 Share Posted December 5, 2003 Well, I've run into some minor issues with the MBC project where my part sizes differed from those of the guy who wrote the instructions! (Basically, the walls of the plumbing parts I have are a lot thinner than those he used, thus there is much more open space inside which makes other parts not fit correctly without upping the sizes appropriately.) I'm going to pick up a few more parts tomorrow after work and that should be all I need to finish the project tomorrow evening! On a related note, I had forgotten how fun cutting stuff with the dremel cut-off tool is...LOL Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 Originally posted by Warp3 Well, I've run into some minor issues with the MBC project where my part sizes differed from those of the guy who wrote the instructions! (Basically, the walls of the plumbing parts I have are a lot thinner than those he used, thus there is much more open space inside which makes other parts not fit correctly without upping the sizes appropriately.) I'm going to pick up a few more parts tomorrow after work and that should be all I need to finish the project tomorrow evening! On a related note, I had forgotten how fun cutting stuff with the dremel cut-off tool is...LOL mine has quite a bit of free room inside, but it all seems to stay together ok. Quote Link to comment Share on other sites More sharing options...
Skip Posted December 5, 2003 Share Posted December 5, 2003 Guys, I am perplexed as to why no overboost control has been expierenced. I can't believe the boost gauge is that badly calibrated. I am questioning this "run out of breath" Here are some thoughts, If it is indeed running out of breath, it could mean the air flow volume through the MAF may not be high enough for the signal voltage to the ECU to increase to the level where it will start the timer. Therefore this timer, which would cause the control when it times out, is not being initiated. Now why is it running out of breath, a) could a restricted air filter be causing it? Could one of the exhaust components be partially plugged (my second cat had broken into chuncks and was obstructing flow) c) cams are of the newer style so hey are not in the equation. As I said my wagon will pull to 7 k+ and even there is showing no sign of running out of steam, I just don't trust running the engine at this elevated RPM for long periods. Hey Tex I need some back up here, am I the only turbo owner with an over boost control programed in their ECU?? I have read where the Euro cars has it programed at a higher MAF signal level but this does fit either Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 'tis strange. I don't think the exhuast is plugged up, as the car runs smooth at all other times. The exhaust is stock except for a glass pack in place of the muffler. (it sounds like a little baby version of my gt! lol....) The intake is a currently a normal filter, but the bottom of the air box has been removed and the little plastic thing from the top of the box has been removed. I honestly think the turbo is just out of breath. I will be getting a little more accurate boost gauge in this weekend, so we'll see where it's really running. I may also turn it back just a couple of pounds this morning and see how it feels. Quote Link to comment Share on other sites More sharing options...
WJM Posted December 5, 2003 Share Posted December 5, 2003 answers! A: No. Pleadies has a bottomless inbox, with all those nice plasti peices removed. I Have a big 3 inch ID 'riceboy' cone filter stuck stright on the MAF with one of those MAF adapters. B: With Pleadies RX, and my GL-10...possibly. But last i had the exh off my GL-10, which wasent long ago...it was solid. Both cars run with no muffler, although Pleadies's RX has a glasspack. My RX has a 2.5" downpipe, with wastegate relief - Similar to the subspeed one. C: c) cams are of the newer style so hey are not in the equation. Huh? You mean the cam profiles from the factory for 85-86 cars vs the 87+ cars? I dont understand why these two cars are not hitting the boost cut either. Ive got a MBC comming, and when I ge thte RX's engine back together, again, then I'll cranck up the boost and see what happens at 14psi. Quote Link to comment Share on other sites More sharing options...
Warp3 Posted December 5, 2003 Share Posted December 5, 2003 Originally posted by pleiades mine has quite a bit of free room inside, but it all seems to stay together ok. The spring size is one thing (and I am going to see if they have a more appropriately sized one), but the major issue was that the recommended 5/16-18 bolt slides freely through the 1/4" NPT coupling because the coupling has relatively thin walls. So I've tapped the insides of the coupling for 3/8-24 instead and just need to get the appropriate bolt/nut combo to match. Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 Originally posted by Warp3 The spring size is one thing (and I am going to see if they have a more appropriately sized one), but the major issue was that the recommended 5/16-18 bolt slides freely through the 1/4" NPT coupling because the coupling has relatively thin walls. So I've tapped the insides of the coupling for 3/8-24 instead and just need to get the appropriate bolt/nut combo to match. Yeah, that's where I actually went with a leftover factory Subaru bolt from some previous stripping project. Oh, and I threaded the pipe piece metric to fit the bolt! So mine is more anatomically correct! ROFLMAO...... Steven Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 We really need to talk about what we know (or what you know) about the hole in the side of the boost controller. I started thinking about it more at lunch, and it seems that no matter how lightly I adjust this thing, the car still seems to boost ~13-14psi. Now, when it really hit me, is when I was adjusting it again, to shoot for 10psi, as I wanted to see if the car got rid of that running out of breath feeling. Ok, so several things that (duh) came into my head when starting to think about why the car wouldn't adjust down to 10psi. First of all, the hole is bad. To be good, it would need a check valve pointed in the direction that it could blow out, but not suck in, otherwise the car has a vaccum leak, right? Also If that hole is really the controlling factor in the MINIMUM boost you can run, right? If we knew what boost we wanted to run, and didn't want to make it adjustable, we could elimate the whole silly spring and bearing mess and just put a hole properly sized for what boost we want & a check valve, right? Also, for anyone else out there that is running a manual boost controller: where do you have it connected? Mine is right in the middle of the line that goes from the wastegate to the boost controller, with the ball bearing pointed towards the wastegate. And you know, that now hits me as incorrect. Maybe the only reason I'm running more boost is the fact that the little hole is leaking all of the time. You know, I think i'm just nuts in fact! lol... Here is another oddity: I put some high quality electric tape over the hole for testing purposes, and the car will now boost to like 14psi and then you shift gears and it won't go over stock boost ~7psi. WEIRD SH*T! Any comments? Skip, Dr RX, Tex??? Anyone? hehe... This is fun. Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 Oh, and can I please request the title "boostaholic" under my name? hehe.... And warp3 needs "Boost, my precious" as he is the most reserved person you will ever meet until you put him in a turbo car! ROFL.... Quote Link to comment Share on other sites More sharing options...
Warp3 Posted December 5, 2003 Share Posted December 5, 2003 Originally posted by pleiades Also, for anyone else out there that is running a manual boost controller: where do you have it connected? Mine is right in the middle of the line that goes from the wastegate to the boost controller, with the ball bearing pointed towards the wastegate. And you know, that now hits me as incorrect. You see...that would be backwards...mmm-kay... LOL The boost pressure is supposed to push against the ball bearing which forces it back (restricted by the spring's tension) and lets air through. It can't do that if the air pressure is pushing on the wrong side of the ball bearing...LOL Quote Link to comment Share on other sites More sharing options...
Warp3 Posted December 5, 2003 Share Posted December 5, 2003 Originally posted by pleiades And warp3 needs "Boost, my precious" as he is the most reserved person you will ever meet until you put him in a turbo car! ROFL.... ROFLMAO...who me? Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 Originally posted by Warp3 You see...that would be backwards...mmm-kay... LOL The boost pressure is supposed to push against the ball bearing which forces it back (restricted by the spring's tension) and lets air through. It can't do that if the air pressure is pushing on the wrong side of the ball bearing...LOL Well I know, and that's why I said I just relized I had it hooked up wrong. But where should it go? Same place, different direction? Different Place? I find it really odd that it was working anyway. lol.... (well sort of anyway ROFL....) Quote Link to comment Share on other sites More sharing options...
Meeky Moose Posted December 5, 2003 Share Posted December 5, 2003 we should change the title of the thread as well... this hole thread is mor informational to me than any little wrinky dink website on it.. now i know not to put it in backwards as well although my RX shouldn't hit a fuel cut since its an 85' .. "i don't need no stinking boost cut!" Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 Originally posted by Meeky Moose we should change the title of the thread as well... this hole thread is mor informational to me than any little wrinky dink website on it.. now i know not to put it in backwards as well although my RX shouldn't hit a fuel cut since its an 85' .. "i don't need no stinking boost cut!" I've been known to stumble upon very interesting findings by doing things the wrong way. It's sort of my trademark! lol.... (are you worried about the boost controller yet? lol.... j/k, I follwed the instructions on the assembly, just not the installation. lol....) Quote Link to comment Share on other sites More sharing options...
Warp3 Posted December 5, 2003 Share Posted December 5, 2003 Originally posted by pleiades Well I know, and that's why I said I just relized I had it hooked up wrong. But where should it go? Same place, different direction? Different Place? I find it really odd that it was working anyway. lol.... (well sort of anyway ROFL....) Right place, wrong direction...put the "ball bearing" end upstream. Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 Originally posted by Warp3 Right place, wrong direction...put the "ball bearing" end upstream. I'll have to swap ends when I leave work. So expect an update about fuel cut or not when I get home ~5pm. Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 Oh, and I guess if you do that, you no longer have a vaccum leak! Damn this actually makes a little sense! ROFL.... Quote Link to comment Share on other sites More sharing options...
Meeky Moose Posted December 5, 2003 Share Posted December 5, 2003 well i think we all know how to get 13-14psi and not hit the fuel cut now, haha, thats one way of findin out.. i think i'll do an intercooler before i run that much tho Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 Originally posted by Meeky Moose well i think we all know how to get 13-14psi and not hit the fuel cut now, haha, thats one way of findin out.. i think i'll do an intercooler before i run that much tho true. It will be interesting to see what it does on the way home after switching it around. Yeah, I want to do that as well. If I get this thing sorted, I will probably back it down to 10psi, as it still feels strong up until just after that. Quote Link to comment Share on other sites More sharing options...
pleiades Posted December 5, 2003 Author Share Posted December 5, 2003 I must say, in my defence, it was sub 30 degrees & dark outside when I installed! lol.... Quote Link to comment Share on other sites More sharing options...
Subarutex Posted December 5, 2003 Share Posted December 5, 2003 Hope you get that MBC flipped around, then try adjusting. My first spring i couldn't get lower than about 20psi. It was too stiff. GOod luck. Skip - Over boost control = fuel cut? IF so, yes, I get it very badly. I'm running a very efficient intake (similar to the wittepro), 12psi boost, and the spider. On the freeway, if i'm on it more than 5-6 seconds, i hit fuel cut. The severity of the fuel cut depends on temperature i think. Sometimes its a lot more violent than others. Now, I've hit fuel cut with as low at 5psi of boost. GOing up the pass, probally an instance of temp, and whole bunch of air being forced through. I do experience my car running out of breath on occasion. Usually only in 3rd or 4th gear. I think its more a gearing issue than the turbo. Come march, you're jaws will all be on the floor, stay tuned. Quote Link to comment Share on other sites More sharing options...
Skip Posted December 5, 2003 Share Posted December 5, 2003 Thanks Tex, was begining to think I had lost what little part of my mind I have left. And thanks for the backup on the spring's rate being important. Let me ask this somewhat foolish question, with the MBC installed backward (and yes it goes in the line to the waste gate control diaphragm) If the check ball was sealing properly, my feeble mind says the wastegate would see no pressure and therefore you would be running with the turbo blowing all it could. This kind of error could lead easily to a blown head gasket. The check ball must be leaking by at its seat. My comment about the most important part. Where do you have the boost gage fitted and is it a vac/boost gage or ?? Also doesn't the website says the small "breather hole" is only an issue at around 20 psi. Think me eyes is goin to! Quote Link to comment Share on other sites More sharing options...
Warp3 Posted December 5, 2003 Share Posted December 5, 2003 Originally posted by Skip Also doesn't the website says the small "breather hole" is only an issue at around 20 psi. Actually it's 15psi according to the website. I'm not sure exactly HOW it makes a difference, though. The way it's worded on the website, it sounds like it's only designed to "equalize" pressure when the MBC is closed and that due to its size would have little effect when the MBC is actually venting. Of course, it IS a DSM site, so maybe it's a workaround for a DSM-specific issue? Quote Link to comment Share on other sites More sharing options...
Warp3 Posted December 6, 2003 Share Posted December 6, 2003 Well, after buying a couple more parts from Lowe's (a 3/8"-24 bolt and nut) and robbing and modifying some parts from an ink pen (the spring itself, plus I used pen parts to make a "sleeve" for the spring to keep it from flexing and binding inside the body of the MBC), my Manual Boost Controller is complete!!! Woohoo! To be on the safe side, the initial setting I chose is the maximum setting that I can still "blow" open. (Then after some research on the web, I've discovered that for the average human that's apparently only about about 1-2psi... ) So in theory when installed it should act as if it has no MBC at all until I start to turn it up. Quote Link to comment Share on other sites More sharing options...
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