Losing boost at 6400rpm. Help!
- Thread starter suprahero
- Start date
Tire Shredder;1136792 said:
I've did this twice and I haven't found any leaks at all. How do you keep air from going through the intake and out the exhaust? I had to remove my downpipe and put a piece of metal like a gasket to seal it off. Am I doing something wrong? Wont' two valves be open at all times? This always confuses me, because I feel the air will just go out the valves and then out the exhaust. Someone please explain this, because unless I block off the downpipe, I can't pressurize my setup. Does this mean their is something wrong? Thanks Steve
I hooked the wastegate up to the turbo this evening and did a datalog. It's the exact same. It's hard to make me mad, but this is really starting to wear on me.
Tlo, I have a Garrett gt35r turbo with a T3 flange.
buckshotglass
I love all your sounds.
I just take mine up to around 6000, and shift.Yours has more power than mine. I need the extra 1500rpm to make mine feel potent!!!!
I'd appreciate it if you didn't come into my thread bragging about how your car doesn't neet to rev that high to make power..........:3d_frown:
I'd appreciate it if you didn't come into my thread bragging about how your car doesn't neet to rev that high to make power..........:3d_frown:
buckshotglass
I love all your sounds.
buckshotglass
I love all your sounds.
Oh boy. That right there is gonna put a hurtin' on this here Hillbilly.ForcedTorque;1137038 said:
I've lost all feeling. I may as well be dead. My car won't boost seventeen pounds after 6400rpm. How can I call myself a supra lover when I could probably be outrun by a stinking porche right now? I've got to get this fixed somehow so I feel whole again. Right now I'm only half a man and I don't know why anyone would want to kick me when I'm down.............:cry:
:biglaugh:
:biglaugh:
suprahero;1136967 said:
OK Jay, I have tested many systems. What you want to do is take the pipe off the Throtle body and plug it some how and good. What I did is use a metal SS pipe cap and use the sylicone coupler with t bolt to plug it up. In this case use what ever you have just make sure you can make it secure.
Once that is done take the pipe off the turbo outlet and put your plug with air fitting and reg on there. Now with any shop air tank adjust the regulator to about 20psi (do not go to high unless you know thise caps are secure). Now listen for any air leaks, what I do is turn off the air at the plug with a sealed shut off valve. Let it sit for 5min and see if I have any pressure drop. If you can hear air leaking you know you have a problem and were.
I have tested systems up to 45psi with this method and it works. You may not have a leak at 15psi but at 20psi it leaks like a stuck pig.
Good luck.
Jeremy
Test everything, its what I've always done. Leave everything hooked up and let her rip. You shouldn't have any flow through the exhaust. If you have some turn the crank till it stops. If it doesn't stop, you found your leak (valves).
I just did this AGAIN for about two hours. I didn't read your post until after I got through Justin. I unhooked the downpipe and put a piece of metal between the two to seal it off and then put twenty pounds of air through it. I don't know where it's leaking but it's leaking somewhere. It doesn't hold the air in it but for about one minute and then there's not a lot in there. I also took the Tial wastegate off and installed the spring out of my HKS wastegate into it and did another test run. It now spools to about fourteen and drops off to nine. I like this spring better so I'll leave it in for now.
I had my head completely rebuilt and I had them install some Crower springs and retainers. Could this be the problem as Justin mentioned. Should I hook the boost leak tester back up and see if turning the crank helps any? If I take the head off, will I be able to tell if they're leaking? I really want to get to the bottom of this. Thanks to all who are constantly checking in and offering advice. Keep the suggestions coming.
I had my head completely rebuilt and I had them install some Crower springs and retainers. Could this be the problem as Justin mentioned. Should I hook the boost leak tester back up and see if turning the crank helps any? If I take the head off, will I be able to tell if they're leaking? I really want to get to the bottom of this. Thanks to all who are constantly checking in and offering advice. Keep the suggestions coming.
suprahero;1137652 said:
Yea turn the crank. There is valve overlap (both intake and exhaust valves will be open at the same time) so it might be leaking by that, but by turning the crank itll close one set of valves. Now the air will leak out, it wont be a 100% seal and the pressure will bleed out slowly (through rings) But you shouldn't have any leak through to exhaust. If you turn the crank and are still having it leak into the exhaust, try pulling the cams out to be sure. If it still leaks then its a valve issue.
Are you saying that on the exhaust side one set of valves won't be open at all times. When I was testing my valves to see how far they opened it seem'd like one set of intake valves were open at all times.
I will test this again tomorrow if I get a chance, if not, it will be thursday since I have a busy day tomorrow. I hope this doesn't end up being something in the head. I mean if it is, they'll fix it for free, but it's going to piss me off that it took me this long to figure it out. I could take the head off and take it back to the machine shop and have them check everything, but I'd at least like to make sure there is something wrong with the head first. Hopefully I can figure out yes or no thursday.
I will test this again tomorrow if I get a chance, if not, it will be thursday since I have a busy day tomorrow. I hope this doesn't end up being something in the head. I mean if it is, they'll fix it for free, but it's going to piss me off that it took me this long to figure it out. I could take the head off and take it back to the machine shop and have them check everything, but I'd at least like to make sure there is something wrong with the head first. Hopefully I can figure out yes or no thursday.
One thing no one has asked is if the valves are shimmed right. If there not you may be holding the valves open a bit. Worth a shot.
Jeremy
Jeremy
Here is a suggestion from of newb. You think you have a leak right. Go back and pressure test the system in smaller sections. Throttle body pipe to turbo outlet as suggested above by Turbo Drifter. If you don't have any leaks there you eliminated that section or closed loop. Then go to the next section or closed loop and pressure test. Try and narrow it down to a specific area.