10MinuteCar Posted January 11, 2008 Share Posted January 11, 2008 (edited) i have a electronic boost controller (Greddy Profec B Spec 2), and the cars pretty much stock except a cat back exhaust. im having a top boost of 11psi but it drops to 8.7 nearby redline. what do you guys think the problem is? I don't think i have any boost leak as i dynoed it to check and the unique auto sports guys says its normal for the stock turbo but they also said a cat back exhaust will help the boost drop less, but it didn't do that. What do you guys think the problem is? i really want a full 11psi boost to redline. by the way the car is GTT R34 Edited January 11, 2008 by 10MinuteCar Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/ Share on other sites More sharing options...
10MinuteCar Posted January 11, 2008 Author Share Posted January 11, 2008 please help! Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3577137 Share on other sites More sharing options...
r32woohoo Posted January 11, 2008 Share Posted January 11, 2008 sounds about right get a split dump and front pipe to help the turbo breathe better in the upper rev range Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3577183 Share on other sites More sharing options...
VB- Posted January 11, 2008 Share Posted January 11, 2008 yeah normal for stock turbo/dump arrangement Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3577344 Share on other sites More sharing options...
10MinuteCar Posted January 12, 2008 Author Share Posted January 12, 2008 wait im so newbie that when you guys always say front pipe i don't get what it is. i know the dump pipe is the single pipe from turbo to the cat but wats a front pipe?? Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3577719 Share on other sites More sharing options...
eddieeeee-ro Posted January 12, 2008 Share Posted January 12, 2008 wait im so newbie that when you guys always say front pipe i don't get what it is. i know the dump pipe is the single pipe from turbo to the cat but wats a front pipe?? dump pipe is straight off the turbo, which leads into the front pipe which is just before the cat. aka dump/front pipe. u can get it in one peice. Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3577765 Share on other sites More sharing options...
10MinuteCar Posted January 12, 2008 Author Share Posted January 12, 2008 so dump pipe will fix this problem of dropping boost? Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3578417 Share on other sites More sharing options...
10MinuteCar Posted January 13, 2008 Author Share Posted January 13, 2008 also whats a downpipe? is that just a dump pipe? Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3578752 Share on other sites More sharing options...
10MinuteCar Posted January 13, 2008 Author Share Posted January 13, 2008 do everyone drop 2 psi on higher than stock boost? even with a eletronic boost controller as well like myself? Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3579090 Share on other sites More sharing options...
Dose Pipe Sutututu Posted January 13, 2008 Share Posted January 13, 2008 do everyone drop 2 psi on higher than stock boost? even with a eletronic boost controller as well like myself? I use to have a case where my rubber intake collapsed causing the boost to drop once the engine bay was warm, and with the silicon intake pipe I purchased, IT MADE IT WORSE ended up going back to the stock intake, and reinforcing it with stainless steel off cuts. Problem solved. I think the reason why your boost is dropping is due to your restrictive exhaust system. Invest in a dump & front pipe and a high flow catalytic. Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3579098 Share on other sites More sharing options...
shnaped_second Posted January 13, 2008 Share Posted January 13, 2008 My 34 drops boost by around 4 pound on redline, i have the boost set to 14psi and by redline it drops to just below 10psi, get used to it mate if your going to keep the stock turbo Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3579321 Share on other sites More sharing options...
tek_01 Posted January 13, 2008 Share Posted January 13, 2008 It is normal, altho mine is dropping from 14psi to about 11psi get a free flowing full exhaust system as suggested before to help it breathe better i would of thought that standard turbs would be able to hold 11psi but i guess not Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3579326 Share on other sites More sharing options...
R33Turbo Posted January 13, 2008 Share Posted January 13, 2008 is it possible to use a r32 actuator inconjunction with the EBC by any chance? Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3579556 Share on other sites More sharing options...
R33Turbo Posted January 13, 2008 Share Posted January 13, 2008 just a question would a exhaust manifold leak cause the boost drop as mentioned before from about 11psi down to 9psi as well? or will it never even reach the 11psi in the first place? Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3579633 Share on other sites More sharing options...
shnaped_second Posted January 14, 2008 Share Posted January 14, 2008 is it possible to use a r32 actuator inconjunction with the EBC by any chance? Yes but you would be wasting your time, I have a adjustable hks actuator and it still drops off boost just a question would a exhaust manifold leak cause the boost drop as mentioned before from about 11psi down to 9psi as well? or will it never even reach the 11psi in the first place? Possible but it would need to be a big exhaust leak Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3580872 Share on other sites More sharing options...
dmr Posted January 14, 2008 Share Posted January 14, 2008 even with upgrading to a bigger front/dump pipe, the stock turbo wouldn't hold anything over 10psi very well. Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3580912 Share on other sites More sharing options...
R338OY Posted January 14, 2008 Share Posted January 14, 2008 just a question would a exhaust manifold leak cause the boost drop as mentioned before from about 11psi down to 9psi as well? or will it never even reach the 11psi in the first place? I just had my leaking manifold repaired. Problem was low boost from low rpms. Once i put the boot in it was hard to notice because there was lots of pressure and i made the 11psi my boost controller was set to. Manifold leak (depending how severe) shouldn't cause high rpm boost loss. Like all the fellas said, it's normal for your setup to lose 2-3psi. Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3581037 Share on other sites More sharing options...
jase-r34 Posted January 14, 2008 Share Posted January 14, 2008 I run a GReddy profec on my GTT also and have found that just playin with the gain setting in particular can help stop the boost dropping off in the higher revs. Im only running 10psi hi boost and still playin round with the settings but have managed to get it pretty good and hold the 10. I also have a 3" system off the back of the turbo that prob helps a bit too tho. Good luck! Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3581044 Share on other sites More sharing options...
R33Turbo Posted January 14, 2008 Share Posted January 14, 2008 I run a GReddy profec on my GTT also and have found that just playin with the gain setting in particular can help stop the boost dropping off in the higher revs. Im only running 10psi hi boost and still playin round with the settings but have managed to get it pretty good and hold the 10.I also have a 3" system off the back of the turbo that prob helps a bit too tho. Good luck! oh great! since we're both using the same cool EBC could u gimme some advice on how to set the settings to hold 10psi boost please? from 1st step to last as ive never tried to touch the EBC myself but will do with the help of a pro Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3581385 Share on other sites More sharing options...
jase-r34 Posted January 14, 2008 Share Posted January 14, 2008 (edited) LOL i am hardly an expert! Ive only had it on there for bout 2 or 3 weeks and been playing with it tryin to get it somewhere right. just went and had a look at my settings and atm they are- set: 40% gain:27 set gain:6psi its holding boost pretty well but needs more fine tuning. also been hard cause ive been trying to do it on my own... My cars mods are just 3" turbo back and a K&N panel so pretty stock... hope that was of some help to ya! oh also just adding the peak boost with those settings was 10.3psi....not sure of the rpm(bit hard to drive and look at it lol) Edited January 14, 2008 by jase-r34 Link to comment https://www.sau.com.au/forums/topic/201169-boost-drops-about-2psi-nearby-redline/#findComment-3581410 Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now