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That is not always the case. The leak could be slight enough that the turbo can make more boost to keep the same boost level. Only difference would be more lag (which I have) and the turbo would be running a lot harder.

I had the blow off valve blocked off for the 279kw dyno above and that still dropped boost. Only difference since then is 20rwkw. Oh well I will just block off the blow off valve and go for a drive tonight.

Sorry I should have said may cause boost to drop off :P

I have a GTR BOV, PM me if you are interested in buying it!

ditch the pile of shit stock bov and run no bov. there over rated and being such a soft spring they will be opening as its ramping up on boost.

My tuner Trent said that the R34 ecu has more smarts built into it and is very hard to get perfect driveability without a bov. He much preferred me to run a bov that returned to the intake.

I thought the stock bov had proved itself to be quite good for 300rwkw??

I am going for the standard engine bay appearance (cause of stupid vic rules) and driveability is very important to me.

ditch the pile of shit stock bov and run no bov. there over rated and being such a soft spring they will be opening as its ramping up on boost.

we usually make over 290-300 on std bov no issues, so they generally are very good. Drive ability and return to idle on the R34 is far superior with it too. The r34 graphs posted above @ 290rwkw are all with std BOV and piping. I advised jeff to bring in a block in plate next time after he had checked all his cooler pipe joiners just in case his was faulty bt they generally are not an issue.

we usually make over 290-300 on std bov no issues, so they generally are very good. Drive ability and return to idle on the R34 is far superior with it too. The r34 graphs posted above @ 290rwkw are all with std BOV and piping. I advised jeff to bring in a block in plate next time after he had checked all his cooler pipe joiners just in case his was faulty bt they generally are not an issue.

Thanks Trent, does a 'block in plate' do the same thing as that rubber cap you put over the bov last time? I was going to put that on tonight and go for a spin.

I was quite happy with the 279rwkw last time with more response, I would like to get there first and then look at improvements later on. The bov is one thing that has changed since then and is also very easy to work on. Taking off front bar and checking/replacing joiners is obviously a lot more work.

What do people think of this bov? Will this perform the same as a standard one ie leaking at idle etc?

http://cgi.ebay.com.au/TURBOSMART-KOMPACT-...=item2c57d74ad6

I love turbosmart products, they have always served me well in the past.

from what i can tell "ABE's" 290kw run has more power and torque pretty much everywhere than the 3071r.. i like that turbo :P

it is also running 3psi less and making basically the same power, be very interesting to see the ceramic bearing version overlayed on the gt3071

actually Id love to see all of your turbos overlayed with similar boost levels, makes it much much easier to compar

If you guys are worried about your BOV do what I did and make a small gasket with a 1cm hole in the middle, it stops the BOV opening as soon and as much, result is it only opens when you completely close the throttle, won't open on half throttle, also when it does it doesnt make a ridiculous PSSSHHHHH noise, it is much quieter and will get a tiny bit of flutter on low throttle changes.

Edited by Rolls
it is also running 3psi less and making basically the same power, be very interesting to see the ceramic bearing version overlayed on the gt3071

actually Id love to see all of your turbos overlayed with similar boost levels, makes it much much easier to compar

If you guys are worried about your BOV do what I did and make a small gasket with a 1cm hole in the middle, it stops the BOV opening as soon and as much, result is it only opens when you completely close the throttle, won't open on half throttle, also when it does it doesnt make a ridiculous PSSSHHHHH noise, it is much quieter and will get a tiny bit of flutter on low throttle changes.

i wouldnt recomend that, my car had that from when it came from japan and i had alot of problems tuning it with that stupid plate in there, once we found the problem and chucked it in the bin i made 20rwkw more! and afrs were a flatline :P

i wouldnt recomend that, my car had that from when it came from japan and i had alot of problems tuning it with that stupid plate in there, once we found the problem and chucked it in the bin i made 20rwkw more! and afrs were a flatline :P

Did you reinstall the bov afterwards? I cant see how a bov restrictor plate could reduce power? Affect driveability sure.

Did you reinstall the bov afterwards? I cant see how a bov restrictor plate could reduce power? Affect driveability sure.

yeah all it is going to do is cause the afm signal to be screwing when you back off the throttle making a pop or two, however with my suggestion it still lets air out the bov, just slower and doesn't open as easily so you avoid the pops and the annoying effects of running a bov.

EDIT: when there is NO pressure on either side of the BOV, does the spring hold it open or closed by default?

Closed, the BOV will start cracking open around 5 psi without the vac hose hooked up. When hooked up properly the boost line from the plenum will help hold the BOV shut.

Thats why I hate bovs its one more thing to eliminate a problem from if its gone but that sucks how with the r34s its harder to get tuned for.

All MAF cars are harder to tune with no BOV, R34s aren't particularly worse than any other nissan motor, the reversion plays funny buggers with the MAF signal causing it to dump fuel, you need to stuff around with tps fuel trim maps etc.

All MAF cars are harder to tune with no BOV, R34s aren't particularly worse than any other nissan motor, the reversion plays funny buggers with the MAF signal causing it to dump fuel, you need to stuff around with tps fuel trim maps etc.

Yeah before my tune it stalled all the time but yeah after tune never stalled on me so if there the same as r33 it can be done.

Thats why I hate bovs its one more thing to eliminate a problem from if its gone but that sucks how with the r34s its harder to get tuned for.

BOV's aren't a problem they prevent them.

+1 ^

You know what often causes problems? Motors. Let's rip that out just to prevent having any problems with it.

Well if you got the chance to eliminate one problem from the list why not do it? They dont cause probelms if the car is tuned to run without it. Anyway up to the individual if you want to run it then thats up to them but personally I dont see a point to them.

Ok I blocked my bov off and it is still laggy and not making the power it should. It used to come on hard at 4,000rpm, now it only starts at 4,500rpm. It feels the same as with the bov plumbed in.

Bugger thats the bov off the list.

Looks like Trents boost leak idea is the next thing to check. I still have my boost leak tester from my previous car so will give that a go as soon as I can find the pump. Any other ideas?

Harey mate why are the diff ratios different on the new sheet??

Have to ask Trent, he did some process to tune it. Dont know much more about it.

I just know the car feels a lot laggier and less power. Dont even really need a dyno but the dyno backs it up how it feels.

Harey mate why are the diff ratios different on the new sheet??

we were comparing different cars so the folder thats opened last will be shown.

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