Need Boost Guru;s Help
#17
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1 bar is atmospheric pressure on the stock gauge so that's 0 boost, just to make it clear
#18
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People always saying they hit 1.75-2 bar that's no possible with the stock gauge, 2 bar will be like 28 psi lol
#19
Thread Starter
Burning Brakes
I will get a boost gauge. Now what I need to figure out is why I'm getting more boost with the wastegate NOT crimped than when crimped.
My pressure testing of the WG with a pump tells me the WG is ok. It stats to open around 4psi and is fully open at 7psi. While it's held open by pressure from the pump I push on the valve and I can feel the diaphragm holding the pressure. When I let out the pressure the valve snaps shut.
My pressure testing of the WG with a pump tells me the WG is ok. It stats to open around 4psi and is fully open at 7psi. While it's held open by pressure from the pump I push on the valve and I can feel the diaphragm holding the pressure. When I let out the pressure the valve snaps shut.
#23
Rennlist Member
I will get a boost gauge. Now what I need to figure out is why I'm getting more boost with the wastegate NOT crimped than when crimped.
My pressure testing of the WG with a pump tells me the WG is ok. It stats to open around 4psi and is fully open at 7psi. While it's held open by pressure from the pump I push on the valve and I can feel the diaphragm holding the pressure. When I let out the pressure the valve snaps shut.
My pressure testing of the WG with a pump tells me the WG is ok. It stats to open around 4psi and is fully open at 7psi. While it's held open by pressure from the pump I push on the valve and I can feel the diaphragm holding the pressure. When I let out the pressure the valve snaps shut.
Now go back and do the driving test again and properly take the boost line out of the loop by disconnecting it from the charge pipe like I mentioned before. Having even a tiny amount of air getting through the "pinched line" will result in a useless test.
Drive carefully, don't keep it floored for more than a second, mid RPMs and higher the boost should go up instantly in proportion to your throttle position.
By the way, it is normal for a stock car to achieve full boost only when you fully depress the throttle and only be at 1.2 bar (stock gauge) at lesser throttle positions and at any RPM. That's just the way the stock system works. It gets worse when your TPS or CV is on its' way out to the point where it never achieves more than 0.2 bar boost.
#24
Thread Starter
Burning Brakes
Went out and bought a boost gauge today but have not hooked it up. I removed my intake and replaced the CV and all the hoses that run to it including the hose to the WG.
Once I get it all back together I will take it for a drive. Assuming no change I will then hook up the boost gauge, pinch the WG line, and run that test. Should thAt still show no boost then I've either got a bad cross pipe, a bad WG, or a bad turbo. I don't think it's the turbo because I felt the cold side shaft and blade and there was negligible movement - tough I guess I can't count it out.
If I don't get boost I'll probably order a new WG and controller an I'll also get a bore scope to try and check the crossover whe the WG is off
Once I get it all back together I will take it for a drive. Assuming no change I will then hook up the boost gauge, pinch the WG line, and run that test. Should thAt still show no boost then I've either got a bad cross pipe, a bad WG, or a bad turbo. I don't think it's the turbo because I felt the cold side shaft and blade and there was negligible movement - tough I guess I can't count it out.
If I don't get boost I'll probably order a new WG and controller an I'll also get a bore scope to try and check the crossover whe the WG is off
#25
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Joined: Jun 2002
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From: Brisbane, Australia
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By the way, it is normal for a stock car to achieve full boost only when you fully depress the throttle and only be at 1.2 bar (stock gauge) at lesser throttle positions and at any RPM. That's just the way the stock system works. It gets worse when your TPS or CV is on its' way out to the point where it never achieves more than 0.2 bar boost.
By the way, it is normal for a stock car to achieve full boost only when you fully depress the throttle and only be at 1.2 bar (stock gauge) at lesser throttle positions and at any RPM. That's just the way the stock system works. It gets worse when your TPS or CV is on its' way out to the point where it never achieves more than 0.2 bar boost.
Rob
Rob
#26
Thread Starter
Burning Brakes
One thought I forgot to share. I did pressure test the system form the j-boot with about 10-11 psi of pressure. The only leak I found was a small one from the air/oil separator seals. However my understanding is that these systems are just under vacuum only not boost and I don't think they are under that much vacuum. Please let me know if I am in error.
#27
Thread Starter
Burning Brakes
Ok I bore scoped my crossover pipe. I went in from the inlet to the wastegate.
Here is a video this is my first borescope so be kind the video isn't great.
Here is a video this is my first borescope so be kind the video isn't great.
#28
Rennlist Member
Have you checked all of your lines out of the turbo to the intercooler back to the throttle body? If you blow one of those lines loose then you go into NA mode. If you were boosting to 1 atm you may have popped on of the connections. Mine normally comes off right after the turbo or just before the intercooler. Also if you knock the boost line to the KLR loose it will do the same thing.
#29
Thread Starter
Burning Brakes
All my lines are very secure. I replaced them all with good silicon hoses and pressure tested the system. I think it's my WG now and I have a Lindsey WG on order.
#30
Thread Starter
Burning Brakes
UPDATE
Problem solved, it was my wastegate. It must have been worn out. Even with 2 shims in it.
The new LR unit is working great. Even if I'm only using it in single port mode.
Problem solved, it was my wastegate. It must have been worn out. Even with 2 shims in it.
The new LR unit is working great. Even if I'm only using it in single port mode.