Overboost with dump open

Benny™

New Member
Joined
Oct 20, 2022
So the TTA has just moved back with me to the central coast, safe to say the car likes being at sea level at 50 degrees with the dump open...

Anyway, saw a guy being a dickhead and cutting people off and didn't let him pass, I look down and my boost gauge is pinned to the top at 20lb, stock is limited to 16.5 could've been higher than 20 since that's as far as the gauge goes. So I let off, got back on and immediately spiked back up to 20. The TTA doesn't have a wastegate actuator adjustment so I'm not sure what to do. It's got 80k miles and has not ever had an issue, I pulled over and saw nothing leaking, no noises, nothing, drove the car home with no issues... For now.

Just wanted some input on this, if any, I've been overthinking it all night. thank you
 
If it's completely stock and has never had a problem with controlling boost in the past start by making sure the wastegate and wastegate solenoid vacuum circuit are all tight and connected properly otherwise the wastegate or solenoid might not be getting the boost signal. Also make sure your wastegate puck is moving freely.

Link: WASTEGATE LINES

A lower density altitude and temps are going to raise the boost as well. From the dead of summer heat to the high 30 degree temps we are seeing in the Midwest right now my boost goes from 24/25psi to 28/29 psi with no adjustments, just change in weather conditions.

Make sure your monitoring your O2 millivolts and watching very close for any KR, if you don't have a way to monitor these I would suggest avoiding WOT until you do. I have to add a good amount of fuel when the outside temps get low to avoid a lean condition.
 
Boost increase with the dump open isn’t that unusual. The dump opens up the exhaust, the engine can breathe better. I run 20 psi through the mufflers. When I open my dump it’s about 23-24. Just because it’s free’d up. Also. The colder the day, the denser the air. If you have a 5.7 chip add some fuel if it’s cold. I have a 6.1 wideband chip so it adjusts for me. Make sure you’re watching your scanmaster.
 
Don’t run the car anymore till you get one. Period. If your chip was at the programmed timing I’ll bet money it was detonating. Be careful… head gaskets aren’t a fun job
 
Don’t run the car anymore till you get one. Period. If your chip was at the programmed timing I’ll bet money it was detonating. Be careful… head gaskets aren’t a fun job
Well unfortunately I have nothing else to drive, but don't drive much anyway. I'll put the money into one when I get the chance though. The car is in good condition, stock and everything. Not sure what you mean about the chip thing, like I said it's all stock.
 
He’s telling you that most of us have shitcanned the OE chips. Eric at TurboTweak makes much more advanced chips for today’s fuel & tuning.

An advancement for drivability & some tuning. Though Eric’s chips are damn close already as you give him your card info.
 
Definitely recommend going through all the plumbing for the wastegate as said above. Make sure the swing arm isn't bound up. I don't know what the stock chip for those cars looks like, but the stock chip for a turbo Regal has something near 22 degrees of timing if I recall. Today's fuel more than likely won't put up with that at the stock boost level, much less 20 psi. Eric (Turbo Tweak) as mentioned here has it all squared away for our cars. Around $100 for a basic v5.7 chip. You just fill out the form on his site with everything about your car, and he'll send you one.

The first thing I would do is buy a Scanmaster, the second thing I would do is order a chip. I would do those things together. The scanmaster may be old tech, but I can assure you it's the handiest tool on the market for a stock car like yours. Mine has saved me heartbreak and partbreak a couple times now, and I have a powerlogger and a wideband also. Mount it somewhere you can see it. If you see knock retard, get out of it, and figure out the cause. It's really that simple. Keep your o2's in a good range, and keep it out of detonation, and it should be fine. Scanmaster is mighty useful for other diagnostics as well. It'll display trouble codes, show you what sensors are reading, etc.
 
How do I test the swing arm? I kind of fiddled with it with my hands and it didn't move but i doubt that's how to test it. I cant be too safe, I definitely don't have the kind of money to restore this motor. Just mainly asked the question to make sure that what I did didn't cause too much damage if at all. Dunno because I didn't sustain the 20lb boost for longer than 5 seconds. I've heard of those chips also, how does that work, kind of like a tuner?
 
How do I test the swing arm? I kind of fiddled with it with my hands and it didn't move but i doubt that's how to test it.

Take the little clip off the end, and pull the wastegate rod off it. Then make sure you can flap it back and forth.



The turbo tweak chips have some adjustability in them and you can use the scanmaster to do it without even removing it from the car. If you fill out the online order form, and your car is in good mechanical shape, it should come pretty close to right, if not a little rich for safety.



I would say the absolute number 1 thing for avoiding an engine teardown right now would be that scanmaster. It's default screen shows you o2 sensor millivolts and knock retard degrees. If you have 0 knock retard, with a stock combo, odds are it'll be fine. If you see knock retard, lift, and figure out what's causing it.
Not to say you can't physically drive the car without it, but I'd stay out of boost until you can keep an eye on the vitals.
 
As far as your question, if you don't have water and oil mixing, leaking, or overheating, it's probably fine. In stock form they'll endure a small amount of detonation, briefly. Definitely would not make a habit of it, though, because it'll catch up to you before long.
 
How do I test the swing arm? I kind of fiddled with it with my hands and it didn't move but i doubt that's how to test it.

Take the little clip off the end, and pull the wastegate rod off it. Then make sure you can flap it back and forth.



The turbo tweak chips have some adjustability in them and you can use the scanmaster to do it without even removing it from the car. If you fill out the online order form, and your car is in good mechanical shape, it should come pretty close to right, if not a little rich for safety.



I would say the absolute number 1 thing for avoiding an engine teardown right now would be that scanmaster. It's default screen shows you o2 sensor millivolts and knock retard degrees. If you have 0 knock retard, with a stock combo, odds are it'll be fine. If you see knock retard, lift, and figure out what's causing it.
Not to say you can't physically drive the car without it, but I'd stay out of boost until you can keep an eye on the vitals.
All I wanted to hear, thanks alot. I'll test out the wastegate tomorrow. I'll buy a scanmaster, and Ill stay outta boost for now(👀). I'd like to keep the car stock as to not have any unnecessary issues, restore it where it needs and whatnot.

Just curious on the scanmaster, that would be able to tell me if there's any active issues in the motor? Or would I need to gas the car once and let it diagnose? Not familiar with them unfortunately. I'll check into the chip.
 
As far as your question, if you don't have water and oil mixing, leaking, or overheating, it's probably fine. In stock form they'll endure a small amount of detonation, briefly. Definitely would not make a habit of it, though, because it'll catch up to you before long.
Well nothing so far, i had an electrical issue today driving it which caused the cooling fans not to work and the car overheated to about 220 for the first time ever, I only drove about 3 miles though.
 
All I wanted to hear, thanks alot. I'll test out the wastegate tomorrow. I'll buy a scanmaster, and Ill stay outta boost for now(👀). I'd like to keep the car stock as to not have any unnecessary issues, restore it where it needs and whatnot.

Just curious on the scanmaster, that would be able to tell me if there's any active issues in the motor? Or would I need to gas the car once and let it diagnose? Not familiar with them unfortunately. I'll check into the chip.


Check this short video out, it was made by a member here. Easier than to type it all out, but it's a handy tool for several different things as you'll see.

As far as using it to tell you how your tune is, yes, it reads roughly real time. Updates about every second, so you'll have to get on the gas a little and watch the o2's and knock to know what it's doing. There is a call back function on it but I've never used it and don't recall how. Stock car, safe tune you'll get different opinions on, but general consensus is o2's in the 750-800 range are pretty safe, if not slightly rich (safer), and 0 degrees of knock retard is the goal always.
 
I appreciate the help from you guys, I'm definitely going to end up buying a scanmaster soon, or at least before the car gets raced. Hope to be able to drive this car all the way to Bates next year. Thanks again fellas.
 
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