Guest bastaad525 Posted August 17, 2003 Share Posted August 17, 2003 Two questions here About the BOV, when I tried to run mine open to atmosphere, it would cause lots of rich problems, not only a big black puff from the exhaust between shifts, but whenever I would decel, say on the freeway, but not completely let off the throttle, the BOV stays open, and the car would lurch and surge. Since then I've routed it back into the intake, between the AFM and the turbo (that is where it's supposed to go right?) and the car runs much better with no more super rich spots. But, I see lots of guys running their BOV's open to atmosphere (not only Z's) how do these guys do it? Do they just put up with the rich spot?? Do programmable fuel systems have a way to get that rich spot out (I assume yes... does that mean anyone with an open BOV is running programmable EFI?)? How else could you drive with open BOV and not have the car run crappy? And about power shifting, as I understand it, this is shifting w/o letting your foot off the throttle right? Does this keep the boost at full? What are the dangers of doing this? I'm not worried about overrevving the engine, since there is a limiter, but what about damaging other stuff? What parts would most likely be affected and possibly break from doing this? Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted August 17, 2003 Share Posted August 17, 2003 Just do it. It's the best way to not have to respool the turbo, and for me it's always good for another tenth or two (but I'm not the best at shifting either.) Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted August 17, 2003 Share Posted August 17, 2003 so you do this a lot? doesn't break anything? Quote Link to comment Share on other sites More sharing options...
Tim240z Posted August 17, 2003 Share Posted August 17, 2003 Eventually, over time, you have the potential for breaking a crank, or gearbox, but I think occasional use is OK. Tim Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted August 17, 2003 Share Posted August 17, 2003 omg breaking the CRANK???? JEEEZ! I figured something like maybe u-joints or possibly premature wear on the tranny, but the crank? YIKES... think I'll avoid doing this... well... okay I do want to try it and see how it feels... I know I've heard this term a lot so a lot of guys must be doing it. Two tenths in the 1/4 huh? Quote Link to comment Share on other sites More sharing options...
BayAreaZT Posted August 17, 2003 Share Posted August 17, 2003 How about 1/2 throttle betwen shifts if you are coordinated enough to do it. That should be enough to keep you on boost. About the BOV question, I think it has to do with MAF system of our stock EFI (or ECCS). The guys running BOVs vented to atmosphere with stock EFI probably have BOVs that close faster which minimizes the rich spot. I tried venting my 1G eclipse BOV to atmosphere and it ran like crap so I switched it back right away (sounded cool though ). If you want to vent to atmosphere you should probably go with a HKS unit. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted August 17, 2003 Share Posted August 17, 2003 BayArea man you and me sound more and more a like every day, both our cars and our driving styles and ideas! I've been trying very hard to perfect that method, not keeping it floored, but not letting off all the way between shifts either... man it's harder than it sounds! The key is just really doing the whole thing as quickly as possible, but's it's not always so easy. I know it's not really a 'good' thing, but one of the bugs I haven't been able to get rid of in my car, is that the revs will always hover for a second before dropping down, after letting off the throttle, between shifts. Hmmm... but now that I think about it I haven't paid attention to see how this may be affecting boost... it's probably not doing a thing for it, in which case, it's still just a bug, and a very annoying one at any time except for when I'm trying to be fast. I also have the 1g dsm bov, and yeah it ran like crap vented. And you do make a good point now that I think about it, most the people I've seen running open BOV's are running aftermarket adjustable ones. I wonder if I crushed the cap down like many people do with the dsm unit, to increase the spring rate, if this would help and allow me to run it open? I keep swinging back and forth on this, but at the moment I'm longing for the cool sound... usually though I go to great lengths to not let on as to what my car's really got going on! Quote Link to comment Share on other sites More sharing options...
Tim240z Posted August 17, 2003 Share Posted August 17, 2003 When I was running the HKS SSV BOV on my stock ZXT, I didn't notice any richness when venting to Atmosphere. I didn't have a A/F gauge or anything, but it never puffed smoke, or stumbled....always pulled very strong.... Tim Quote Link to comment Share on other sites More sharing options...
lifegrddude Posted August 18, 2003 Share Posted August 18, 2003 If you can get a hold of an HKS EIDS you can vent to the atmosphere all you like without the rich problem, that's how most of the guys in Japan are doing it. The EIDS splices into the AFM signal wire and corrects it anytime the signal has a sudden change such as venting the bov. I bought one while I was in Japan, but haven't installed it just yet. John 82ZXT Quote Link to comment Share on other sites More sharing options...
Guest scottjuly79 Posted August 18, 2003 Share Posted August 18, 2003 I believe that if you are running a MAP sensor as opposed to a MAF sensor, you will not get a "rich/lean" condition when shifting gears. Most of the aftermarket EFI setups use a GM 3 bar MAP sensor, so running the BOV vented into the atmosphere is not a problem. I will be converting to a MAP sensor when I get my Greddy E-manage setup in a couple of weeks here. I personally don't like the idea of routing a BOV back to the intake side of the turbocharger as this would re-heat the intake air as it re-compresses it(it can't be good fo the intake air temp. to compress it twice over!). Does this make sense to anyone else?? Quote Link to comment Share on other sites More sharing options...
fl327 Posted August 18, 2003 Share Posted August 18, 2003 I vent to atmosphere, oh yes I do. I think car runs better, or it runs the same but now goes WHOOSH Between shifts. The recirculating type takes all the joy out of it for me, all the glory. With the T3, Im back in boost right after I hit the gear, There is no kinda lag with this turbo and a vented BOV. Plus it makes that great sound. I do not encounter a stumble either, I run HKS SSQV, it opens and closes FAST, I dont even think the system realizes air loss since it opens and closes so quick, so surge either. WHOOSH. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted August 18, 2003 Share Posted August 18, 2003 I may pick up that HKS BOV since everyone rates it so highly. First I'll try crushing the cap on the DSM unit, as many eclipse guys have done... see if that helps. I do notice a very short lag between shifts before the turbo gets back up to speed, fractions of a second, and part of me is not so sure it's supposed to be there and is another 'bug'. Quote Link to comment Share on other sites More sharing options...
yo2001 Posted August 18, 2003 Share Posted August 18, 2003 Sequential is suppose to not leak under partial throttle. You can tighten the BOV to keep the BOV from opening too much/too early. I don't think EIDS will work on stock AFM setup. I'm getting one for my car but I do have MAF setup instead. Quote Link to comment Share on other sites More sharing options...
spork Posted August 18, 2003 Share Posted August 18, 2003 I'm running the turboxs RFL which vents to atmosphere on my 83 280zxt w/ the stock fuel setup. The RFL vents really fast but it still runs a little rich between shifts...but who cares...I haven't noticed any thing thats made my car run any worse. By the way, when they say its RFL....damn...they mean it. It took some getting used to. James Quote Link to comment Share on other sites More sharing options...
fl327 Posted August 19, 2003 Share Posted August 19, 2003 Yo is right, the HKS super sequential does not vent at idle, even at the loosest setting. RFL is LOUD Quote Link to comment Share on other sites More sharing options...
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