boost drop again
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From: its as intense as the time i forgot how to sit down
boost drop again well ill try again and all the keyboard tough guys stay out of my thread,if you dont have any answers then dont bother typing,so one more time,the kit is sadly to say a qmp kit,and i have been having severe boost drop issues,i know the kit is installed right and the tune is good,could this possiblly be a waste gate problem,or does anyone know of a place that is really good with turbos that could help with this problem
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From: Toronto, Canada
How long have you been running the kit, have you made sure there are no manifold leaks/cracks? Is everything buttoned up tight?
Check the downpipe where it connects into the drivers manifold, it's very tight in there and hard to get it to seal correctly.
I ran a wastegate with no BOV and even when I had everything working as best as possible I was never able to cure the boost drop issues only reduce their severity.
I could go into the other issues but I would need to know your motor better. Boost loos can be caused by turbo stall, leaks/cracks in the exhaust, back pressure problems, damaged/improper wastegate springs etc. What have you already checked and I doubt your tune is causing issues?
Check the downpipe where it connects into the drivers manifold, it's very tight in there and hard to get it to seal correctly.
I ran a wastegate with no BOV and even when I had everything working as best as possible I was never able to cure the boost drop issues only reduce their severity.
I could go into the other issues but I would need to know your motor better. Boost loos can be caused by turbo stall, leaks/cracks in the exhaust, back pressure problems, damaged/improper wastegate springs etc. What have you already checked and I doubt your tune is causing issues?
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From: its as intense as the time i forgot how to sit down
well the motor is stock,and i have welded several poorly welded exhaust/intercooler pipe leaks,the only thing i havent done is check the wastegate spring,but im not sure if the controller should override it or not
On The Tree
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From: Charlestown, Indiana
Take it to Job Spetter at Turbo People of NY. Then come back on the net and tell everyone what was hooked up (or tuned) wrong.
A few things to check before you waste Job's time, and cost yourself a LOT of money:
1. What is the REAL A/F when the boost drops? (an overly rich condition will also cause boost drop)
2. Are the lines to the boost controller ABSOLUTELY, POSITIVELY, hooked up correctly? If so, please give everyone here details of how the lines are ran.
3. Is the E-Boost set correctly? i.e. Overboost setting, Wastegate setting, etc.
4. Are you 100% POSITIVE that you have no exhaust leaks on the pressure side at WOT. Note: I said at WOT, not at idle.
Lastly, these kits CANNOT BE TUNED WITHOUT USING A TRUE WIDEBAND O2, ON THE DYNO!
A few things to check before you waste Job's time, and cost yourself a LOT of money:
1. What is the REAL A/F when the boost drops? (an overly rich condition will also cause boost drop)
2. Are the lines to the boost controller ABSOLUTELY, POSITIVELY, hooked up correctly? If so, please give everyone here details of how the lines are ran.
3. Is the E-Boost set correctly? i.e. Overboost setting, Wastegate setting, etc.
4. Are you 100% POSITIVE that you have no exhaust leaks on the pressure side at WOT. Note: I said at WOT, not at idle.
Lastly, these kits CANNOT BE TUNED WITHOUT USING A TRUE WIDEBAND O2, ON THE DYNO!
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From: Toronto, Canada
I do agree with Rob, that unless the car is tuned with a wideband your only guessing and that could lead to a world of hurt. It's virtually impossible to know for certain if the car is too rich or too lean, too much timing and any of those could hurt the turbo and the motor. Just a thought, what are your running temps on the engine, you'll usually see more heat than stock but is the car running a lot hotter than normal?
You obviously have a bost guage on the car, is it in good working order? My first Autometer boost guage showed 17 psi spiking to 20 and dropping off to 7 from 4500 - 6000. I knew that was wrong and it turned out the guage was toast
that laugh was on me for sure 
Do you know what spring is in the wastegate? I'm sure you have the QMP supplied wastegate, I wanted a 10 lb spring and ended up with a 5 that I changed out myself.
Pressure drops will only be related to the boost side of the kit so the problem is definitly there. From the beginning check your exhaust system again, you will have to go over the entire thing. The most likely culprits are in the areas that I have already mentioned.
Blow bye can cause drops if it is severe enough. What does your oil look like is it burning up and black. If the kit is sound for leaks and the wastegate and boost controller are functioning correctly, you might have hurt the rings.
I can't stress enough with a turbo car how important knowing your AF is. This alone could save alot of problems
You obviously have a bost guage on the car, is it in good working order? My first Autometer boost guage showed 17 psi spiking to 20 and dropping off to 7 from 4500 - 6000. I knew that was wrong and it turned out the guage was toast
that laugh was on me for sure Do you know what spring is in the wastegate? I'm sure you have the QMP supplied wastegate, I wanted a 10 lb spring and ended up with a 5 that I changed out myself.
Pressure drops will only be related to the boost side of the kit so the problem is definitly there. From the beginning check your exhaust system again, you will have to go over the entire thing. The most likely culprits are in the areas that I have already mentioned.
Blow bye can cause drops if it is severe enough. What does your oil look like is it burning up and black. If the kit is sound for leaks and the wastegate and boost controller are functioning correctly, you might have hurt the rings.
I can't stress enough with a turbo car how important knowing your AF is. This alone could save alot of problems
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On The Tree
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From: Charlestown, Indiana
Originally Posted by Warbird
Check the downpipe where it connects into the drivers manifold, it's very tight in there and hard to get it to seal correctly.
Originally Posted by Warbird
I was never able to cure the boost drop issues only reduce their severity.
Originally Posted by Warbird
Boost loos can be caused by turbo stall, leaks/cracks in the exhaust, back pressure problems, damaged/improper wastegate springs etc.
Last edited by smokinHawk; Aug 6, 2004 at 05:48 AM. Reason: removed unnessasary words
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Verdad Gallardo TECH Enthusiast
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From: Toronto, Canada
Originally Posted by Pro Stock John
transdamit please use punctuation and break up those run-on sentences, very hard to read.
Transdammit wrote:
Well I’ll try again, all you keyboard tough guys stay out of my thread. If you don’t have any answers, then don’t bother typing. One more time; The kit is sadly, to say, a QMP kit and I have been having severe boost drop issues. I know the kit is installed correctly and the tune is good, could this possibly be a wastegate problem? Does anyone know of a place that is really good with turbo's, and could help with this problem?
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From: Toronto, Canada
Rob, say your piece and stay away from my comments, they were not directed at you and quite frankly I have no intention of being baited.
I experienced similar issues and was able to correct most of them over time with a lot of helpful outside help. I stand by my comments and do know where the weak points in the kit are. I have no intention of making any derogatory remarks about you or your company. I will continue to try to help so stop being so damn defensive.
I experienced similar issues and was able to correct most of them over time with a lot of helpful outside help. I stand by my comments and do know where the weak points in the kit are. I have no intention of making any derogatory remarks about you or your company. I will continue to try to help so stop being so damn defensive.
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I'm gonna give a wild guess and say it's either the wastegate or blow-by. If you have exhaust coming out of your crank case breather (smells like fuel) then your rings are shot. If not, check wastegate... try different one... if your problem is fixed, wa-la... The default HKS wastegate spring that comes with the qmp kit is from what I understand a 5.9 spring.
http://www.hksusa.com/products/?id=810 with a boost controller you should be able to get 9-10psi before the spring lets go. it's not unheard of for a ebc to be at fault either... they have components that can fail as well.
And to answer ricer eater from the last thread, my car will be done by October. Not going to have the money in time to put a transmission in the car any time soon. Once I get a tranny and rear, maybe a cage, then I'll let MM buy me that beer.
http://www.hksusa.com/products/?id=810 with a boost controller you should be able to get 9-10psi before the spring lets go. it's not unheard of for a ebc to be at fault either... they have components that can fail as well.
And to answer ricer eater from the last thread, my car will be done by October. Not going to have the money in time to put a transmission in the car any time soon. Once I get a tranny and rear, maybe a cage, then I'll let MM buy me that beer.
Last edited by 02BlueFirehawk; Aug 5, 2004 at 01:46 PM.
Have to be careful when you look at blowby issues, remember you will have some smoke it's afterall an engine. A car with a bad or broken ring will run poorly and the smoke will be major. That is what I saw on one car with a blower.
transdam, why don't you put together a checklist, and show what you have checked.
transdam, why don't you put together a checklist, and show what you have checked.
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From: its as intense as the time i forgot how to sit down
like i said before lingenfelter people like you are th reason the posts get locked if its not constructive stay out of it,now for the knowlagable people,the a.f is axactly 11.5 across the board,and timing is 16,there is no exhaust leaks no blowby,and no intake leaks,so its leading me to belive that it is most likely a bad wastegate,im also leaning towards that because the bov was defective when i recived the kit too.
sorry about my typing i am affully stupid and am always in a rush,i work 3 jobs and dont have much time to practice perfect typing,i will try a different wastegate and se what happens.
sorry about my typing i am affully stupid and am always in a rush,i work 3 jobs and dont have much time to practice perfect typing,i will try a different wastegate and se what happens.
when i had the system with the 63mm it would do no more than 10psi. this included buying an entire new wastegate. if you were dropping to 10 thats what i would tell you but since it is dropping so much lower i at this point have to hope that it is something else. if i hadn't sold the w/g allready i would send to you to try.
btw it is a PITA to pull and replace the wastegate while the manifold is in the car. def have a helper available.
btw it is a PITA to pull and replace the wastegate while the manifold is in the car. def have a helper available.
On The Tree
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From: Charlestown, Indiana
Originally Posted by Transdamit
the a.f is axactly 11.5 across the board
Please explain to us how your AF can be "exactly 11.5 across the board" when you have a supposed boost drop issue? If the boost were dropping, the computer wouldn't know that. The stock PCM can't compensate for boost changes. So if the boost varied, as you say, then the AF could not possibly be "exactly 11.5 across the board".
I guess we could make this much more simple. Just post a copy of your dyno sheet AF graph. I'd love to see it.
And FWIW, I am trying to be helpful. But when things don't add up, they don't add up.
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From: its as intense as the time i forgot how to sit down
ok first off princess im not lying,and yes they do drop slightly only because we compensated for the drop,to see if leaner would fix it and it didnt,so dont say you are trying to help if in the first sentence you call me a lier
Trans, Job Jr is the best in the NorthEast when it comes to Turbos...he'll even come to your selected Dyno to tune, but since hes in Amnityville NY, Just drop off the car, with some $, and pick it up done. And it will be done. All I can do is share experiences of some locals who have used Turbo People and each car is basically a daily driver...one a 8.1 176 car that is as reliable as my chevy pick-up. I do think Rob was trying to help in this instance based on his recommendation...of course he wants all of his kits to work great for obvious reasons.
Get it done now so we can run the turbos at LVD in OCT!
Get it done now so we can run the turbos at LVD in OCT!
On The Tree
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From: Charlestown, Indiana
Ok sweetie. Now post up that graph.
BTW, "lier" is spelled "liar", and if you told everyone that your AF was "exactly 11.5 straight across", and then after being questioned about it you say "yes they do drop slightly ", then yes, that's a lie.
Now that you know how to spell the word, look up the meaning.
BTW, "lier" is spelled "liar", and if you told everyone that your AF was "exactly 11.5 straight across", and then after being questioned about it you say "yes they do drop slightly ", then yes, that's a lie.
Now that you know how to spell the word, look up the meaning.