Help Understanding Overboost Protection
#121
Addict
Rennlist Member
Rennlist
Small Business Partner
Rennlist Member
Rennlist
Small Business Partner
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Yep, most likely you either have an aftermarket KLR chip and/or a shimmed wastegate, producing too high of boost for your factory DME chip.
Factory boost is 11psi +/- 10%
Either figure out how to lower the boost, or just get an aftermarket DME chip, which raises the overboost protection.
Factory boost is 11psi +/- 10%
Either figure out how to lower the boost, or just get an aftermarket DME chip, which raises the overboost protection.
#122
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Omni/Rogue, I installed the boost gauge and it seemed like it was holding up fine, then a few days after I took the car out to see how it was boosting and it felt very slow and didnt have much pick up at all. The turbo boosted slow and didnt kick in as hard and peaked at about 12 psi down from 14.5 psi before i messed with the boost gauge. So i figured the vacuum T i put in was leaking...so...I got another better fitting one and installed it carefully. Still same thing.
The car doesnt pull hard at all and it seems to be losing power in the top end under higher load (ie 3rd 4th gear high rpms). Maybe I damaged the klr line somehow but it seems ok...? Do these symptoms coincide with a Boost Leak? How can I pressure test it for a boost leak? I really think I installed the gauge correctly, it was working fine after I put it in, then all of a sudden BOOM low boost and reduced power....HELP!!! Thanks guys!
The car doesnt pull hard at all and it seems to be losing power in the top end under higher load (ie 3rd 4th gear high rpms). Maybe I damaged the klr line somehow but it seems ok...? Do these symptoms coincide with a Boost Leak? How can I pressure test it for a boost leak? I really think I installed the gauge correctly, it was working fine after I put it in, then all of a sudden BOOM low boost and reduced power....HELP!!! Thanks guys!
#124
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Thanks Rogue! So it def sounds like boost leak im assuming. My problem is I dont have a compressor...im trying to borrow one but otherwise can I buy an in-line regulator somewhere cheap to regulate shop air to about 14 psi? Where can i find one that would work and is cheap? I can get a compressor for 60 bucks at harbor freight but I dont know if its adjustable and how well it will work.
#125
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Which exhaust are you using? Which wastegate? Does the cutoff kick in when in higher gears only (3rd, 4th and 5th)?
#126
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
+1 on the aftermarket chip. For reasons I don't fully understand, a bigger exhaust and different wastegate can make the stock chip think there is an overboost issue. Had a similar problem with my track car. Aftermarket chip fixed it. I'm using a 3" exhaust, cat delete and Lindsey racing wategate.
Hey Rouge you think its possible to use a tire Valve Stem on the DIY cap for the intake tube to pressurize the intake system? I dont have a compressor and shop air at work is unregulated besides if I could use a tire filler gauge to stop the pressure at the desired PSI. What you guys think?