^i am about to do this on my 2nd gen jdm 3sgte. I have stock ct26 turbo boosting to 17psi.. is this too much boost to keep locked up or can i block off the bov plate and let the compressor surge without doing damage? I want to do this for a few reasons: my afm metered 2nd gen hicups with the stock bov vented to atmosphere, and i love the surge sound its so sick. Also i hear it drastically improves off boost throttle response.. feedback?
WrenchswingeR
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It depends on what you call "too much damage" you *should* only blow the turbo and the intake fins will get shot into the intercooler. I would have to assume it would be fairly loud, and depending on when it happened you could cause an accident; which I would consider "too much damage". Now most likely you should just break off the intake side's turbo fins; which will cost you a CHRA or new turbo, and just have to clean the fins out of the intercooler. So if you consider even that "too much damage", then yes you will, if you don't, then no you wont.
I've been bov-less since earlier this year. The only concern I had was the possibility of air hitting the afm door and pushing it shut. But I figure if the st185's haven't had any problems running bov-less stock then I wont either...
I made a quick BOV block off plate to do the job and it looked ghetto. I made a new pipe without a flange and looks much cleaner.
Edit: Forgot to mention throttle response was improved.
I made a quick BOV block off plate to do the job and it looked ghetto. I made a new pipe without a flange and looks much cleaner.
Edit: Forgot to mention throttle response was improved.
Some good discussion here on removing the BOV: http://mr2oc.com/showthread.php?t=390783
vr4, got anything to back up your statements?
vr4, got anything to back up your statements?
bro cool it with the 2 much damage.. obviously i dont want ANY damage to anything. I know there are members here running a blocked off bov plate with no problems. Some boosted motors come this way from the factory (300zx, etc). So as to not cause "too much damage", just post useful info plz and not a "too much damage" rant. Any knowledgeable guys out there..galantvr4wd said:
Just because you don't like what I wrote doesn't mean I'm not knowledgeable.WrenchswingeR said:
http://store.forcedperformance.net/merchant2/merchant.mvc?Screen=Info_Turbofailure
I really didn't think I'd actually have to justify why Toyota and many other car manufactures, as well as after market and tuner endorsements say you should have a BOV.
You can usually get away with no BOV with a leak on the intake side of the intake tract (that will give the positive pressure somewhere to go), or with low boost.
If I need to give more justification that I have I guess I can
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The math has been done... The forces that cause compressor surge when the throttle plate closes pale in comparison with the other forces that are going on in there...
Numerous Video evidence has proven that pre-throttle plate pressures dont spike that much after a hard pull and and abrupt throttle close.
Turbo RPM speed sensor measurements have also proven little to no evidence that there are spooling improvements.
Ill be honest with you, I too used to think that a BOV was put in place to protect your engine from damage. But I think it was Texas awhile back who said that how much force do you honestly think 40psi of air in a 3 or 4 liter space has on an object that generates as much torque as your crankshaft spinning at 8000 RPM, Im talking of course about your turbo spinning at 100000RPMs...
Race car drivers NEVER use them... the only people that do are OEMs to reduce engine noise, and fanboy ricers...
The only time compressor surge is bad is if you are on boost. This means your turbo is improperly sized for you engine...
Numerous Video evidence has proven that pre-throttle plate pressures dont spike that much after a hard pull and and abrupt throttle close.
Turbo RPM speed sensor measurements have also proven little to no evidence that there are spooling improvements.
Ill be honest with you, I too used to think that a BOV was put in place to protect your engine from damage. But I think it was Texas awhile back who said that how much force do you honestly think 40psi of air in a 3 or 4 liter space has on an object that generates as much torque as your crankshaft spinning at 8000 RPM, Im talking of course about your turbo spinning at 100000RPMs...
Race car drivers NEVER use them... the only people that do are OEMs to reduce engine noise, and fanboy ricers...
The only time compressor surge is bad is if you are on boost. This means your turbo is improperly sized for you engine...
Haha..yeah, me too. Maybe when I build another motor, I'll try it on the old one before I swap.rocklizzard91 said:here we go again! and yet again i am far too scared to go bov-less
It depends on what you want. If you either like the BOV sound, or you like a quiet motor, then use a BOV.
If you are building a car that you actually want to go fast then go without...
The lie is that a BOV provides any degree of protection for your motor.
Its a tool used by BOV manufacturers to scare you into buying one.
If you are building a car that you actually want to go fast then go without...
The lie is that a BOV provides any degree of protection for your motor.
Its a tool used by BOV manufacturers to scare you into buying one.
Nothing in your link makes reference to damage caused by off-throttle compressor surge. I've yet to find ANY case of a turbo that was damaged by said phenomenon (that wasn't misdiagnosed).galantvr4wd said:
Corky Bell, author of Maximum Boost has publicly stated the he's never seen a turbo damaged by off-throttle surge.
We could rehash this all over again, but it's already been said. Pablo posted the link.
What it boils down to is if it makes you feel better, run one. If you want better boost response between shifts, remove it. The turbo can handle it.
Me? I'm 2 years on a 20 year old turbo (from a vehicle that never had an oem BOV) at ~20psi with no problems. The car is faster without it, so that's the road I've chosen. Do the research and make your own decision.
Another happy BOV-less user here. LOVE the feel of the car without it and had zero problems with the turbo or ever seen any damage caused by off-throttle surge like said above.
On throttle surge is a whole different can of worms and can cause problems.
Also, small correction to an earlier post where i got credit for the math behind the turbo to flywheel comparison, that was actually scarecrow that did that math IIRC. I just checked it out and found it to be correct with some google searching. It even surprised me.
On throttle surge is a whole different can of worms and can cause problems.
Also, small correction to an earlier post where i got credit for the math behind the turbo to flywheel comparison, that was actually scarecrow that did that math IIRC. I just checked it out and found it to be correct with some google searching. It even surprised me.
The ST165 and ST185 came OEM without them.... as did the WRC ST205.
They only put it on the regular ST205 cuz there was a big hole in the intercooler where the rally version routed its boost pressure for the bang bang ALS.
They only put it on the regular ST205 cuz there was a big hole in the intercooler where the rally version routed its boost pressure for the bang bang ALS.
thinking of trying this as well. although the seals on my turbo are already starting to leak, if it goes it goes. got 148k on the original '92 engine. if it blows, in goes a gen3 with accompanying ct20b. someone should make a block of plate kit, maybe ats? ko racing? i think i'll just have a custom one-piece pipe fabbed up.
funny how everyone on here is a huge fan of removing things like the egr system that are PROVEN to lower combustion temps in the situations where they are being used (part throttle driving, combustion temps are lowered, gas mileage is better, etc etc) only to gain a cleaner bay, yet the stock BPV actually takes up just as much room and removing it altogether and replacing it with a custom pipe that has no provision for the BPV will gain you something removing the egr and charcoal canister never will. and thats the gain in boost response between shifts that everyone is talking about.
im going to have a custom pipe made when i install my ems smic and ats tb inlet.
itd be great if one of the forum vendors would make a pipe to replace the stock hot pipe that was designed with no bov port. or even just a block off plate for the stock pipe!
just want to add that i also blocked off the egr system on my own car, so im not hating on people. but if you're wanting to clean up the bay, then go all out! my egr ports were clogged anyway. i'll commit to this. give it a couple weeks to have the pipe made, the guy i use is pretty backed up with other much more higher end projects than my lowly sw20 so i've gotta wait on him.
funny how everyone on here is a huge fan of removing things like the egr system that are PROVEN to lower combustion temps in the situations where they are being used (part throttle driving, combustion temps are lowered, gas mileage is better, etc etc) only to gain a cleaner bay, yet the stock BPV actually takes up just as much room and removing it altogether and replacing it with a custom pipe that has no provision for the BPV will gain you something removing the egr and charcoal canister never will. and thats the gain in boost response between shifts that everyone is talking about.
im going to have a custom pipe made when i install my ems smic and ats tb inlet.
itd be great if one of the forum vendors would make a pipe to replace the stock hot pipe that was designed with no bov port. or even just a block off plate for the stock pipe!
just want to add that i also blocked off the egr system on my own car, so im not hating on people. but if you're wanting to clean up the bay, then go all out! my egr ports were clogged anyway. i'll commit to this. give it a couple weeks to have the pipe made, the guy i use is pretty backed up with other much more higher end projects than my lowly sw20 so i've gotta wait on him.
I just had an idea.
If you really like the noise the BOV makes, but you still want the performance that not running one gives you. Then you could compromise and install an electronic solenoid valve on the BOV vacuum line. And install a switch in dash, or link it with the VSS so that at a stop the BOV will open, but if the vehicle is moving the BOV remains shut.
That way if you are actually racing, it stays off, but if you pull up to the line with some dude and you want him to hear your cool BOV sounds as you blip your throttle you wind up with the best of both worlds.
If you really like the noise the BOV makes, but you still want the performance that not running one gives you. Then you could compromise and install an electronic solenoid valve on the BOV vacuum line. And install a switch in dash, or link it with the VSS so that at a stop the BOV will open, but if the vehicle is moving the BOV remains shut.
That way if you are actually racing, it stays off, but if you pull up to the line with some dude and you want him to hear your cool BOV sounds as you blip your throttle you wind up with the best of both worlds.
meh, i think the surging sounds alot cooler than the bov whoosh. i've got another car that has the ssqv as well, although now i think i'll just sell the ssqv and not run a bov on either car, depending on how well it works on the mister2.
well i just read the thread on the link above. not the one to fp's site, but the one to the other discussion regarding going bov-less. was it the general experience that its not that great on the maf-equipped cars as it induces bucking and things of that nature? i'd rather avoid that, i guess if i go gen3 down the road i'll go bov-less if this is indeed the case.
well i just read the thread on the link above. not the one to fp's site, but the one to the other discussion regarding going bov-less. was it the general experience that its not that great on the maf-equipped cars as it induces bucking and things of that nature? i'd rather avoid that, i guess if i go gen3 down the road i'll go bov-less if this is indeed the case.
Here are pics of my stock ct26 when i first purchased my car. Note that this car surged alot under slight boost/WOT pulls and letting off. It had a nissan check valve of some kind and did it till i put a toyota vtv on. I am not saying you guys are wrong to run no BPV but this was my experience with surging on a ct26 and what the fins looked like after i pulled it off to replace it. The pics don't show the full extent of the damage but the fins are bent backwards, forwards, just kinda all over the place and not sure why, i assumed it had something to do with the surging i was hearing but maybe not. However when i finally fixed the vtv i have had no issues with surging or bent fins like you see with this ct26. Yes it could have been possible the PO of this turbo introduced foreign matter into the turbo which could have bent the fins but i would have thought foreign material would have chipped one of the blades. You be the judge of it i am just showing what this turbo looked like with a definite surging problem.
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