power after forge wastgate install

[vinnieTy]

I installed my new forge wastegate that i purchased from sportmachines a few weeks ago and I have to say BOY was i thrilled of the throttle response the truck had it was unbelievable. Even at half throttle and low rpm the truck pulled very nice. I knew i had to adjust the rod because it overboosted once so i kept in control of the throttle when i drove it. Tonight i started to adjust the rod and using datamaster to run logs and i have to say i have no idea what i did but the truck doesnt pull like it did the first day i installed the newe waste gate.
Data-master is stating im at 15.3 pounds of boost where i have the turbo tweak chip that is set at 17 pounds. I plan to adjust the rod a little bit more but is there something else im missing? Im adjusting by jacking passenger side up and going through fender well. I pull the clip off and turn the rod to the left which is to loosen it to lower the boost and turning it to the right like tightening it to raise the boost. Let me know what you guys think. Maybe i can send someone the data file if they can review it and see something more or less what im seeing.

Thanks
:rant:

 

[Damian]

Re: power after forge wastgate install

Just shorten the rod a half a turn at a time ad long as you aren't getting knock retard.

 

[TYTILIDIE]

Re: power after forge wastgate install

Check to make sure you didn't have any vacuum lines pop off or blow a hole in your turbo to ic tube.

 

[Couger1968]

Re: power after forge wastgate install

From what i understand it doesn't matter what the turbotweak chip is set at, if your forge is hooked directly to the turbo. I didn't have much luck increasing boost by turning the rod, it did raise , but so did my spikes. I got a red spring and I have much better results for 18 psi

 

[Don W.]

Re: power after forge wastgate install

From what i understand it doesn't matter what the turbotweak chip is set at, if your forge is hooked directly to the turbo.

This part is correct.

 

[johne30m3]

Re: power after forge wastgate install

This part is correct.

So the tt chip only affects it if you are still controlling boost with the factory boost solenoid right?

 

[Sportmachines]

Re: power after forge wastgate install

^^ Correct. Few other things.

with the higher initial boost level, you probably had more preload on the spring, and made it more responsive. Also, when turning the rod in, make sure that you are turing the end, and not the whole rod, as that won't adjust anything, it will just spin and you have the same overall length.

Cougar, thanks for sharing you findings with the red spring. He was having some battles with the spikes and holding higher boost. The red spring is rated for 18-22psi, but has more tension, so it controls the boost bit better. And as you guys are probably finding, the adjustable range for the springs is bigger than the claimed 4psi.

Hope that helps.

 

[Couger1968]

Re: power after forge wastgate install

Mine works well, it doesn't spike at all, but the one thing it does still do is drop boost slowly. It jumps to 19 then will slowly drop to high 17-18 as I run. I was wondering if there is a way to hook it up after the intercooler and if it would help. The electronic controler held much closer over the run, but caused spikes.

 

[IGottaSy]

Re: power after forge wastgate install

Disclaimer... don't have one of these but...
if I did, I'd get a stiffer spring that wouldn't start to creep when initial preload is set. So, you want 17-18 psi then spring for 18-22psi would hold better before it starts to creep open at your preset load holding the boost. I'd save some gas and wear and tear by bench setting it to the boost goal.
A wastgate will open slightly as it reaches the boost goal and open completely about 3-4 psi later, for the most part. As stated above, use a stiffer spring.
This...Wastegate Spring Rate and Spring Pre-Load Explain…: http://youtu.be/LStlqe64m4M

 

[Couger1968]

Re: power after forge wastgate install

That is what I thought. I only have it just holding the wastegate shut. It seemed to me the more preload (shortening of the rod) the worse it gets. I suspect what is happening to me is as I run the air is warming up. I have the wastegate hose on the turbo. The intercooler is cool and the air is 19psi at the turbo and the intake. As i run the air is still 19 at the turbo ,but the intercooler heats up and the air is less dense and starts to drop psi at the intake.The factory electronic got it's signal at the intake so it compensated for it. That is why I was wondering if I got my signal for the wategate after the intercooler it would be more accurate. I wouldn't think after the throttle plates would be good for the turbo without a BOV, so in between the intercooler and throttle body. My intercooler doesn't cool as good as it should. Exaggerating the problem. It can go from 100 to 150 degrees by the end of a run. I think I need to reroute my lines.

 

[Don W.]

Re: power after forge wastgate install

Couple of questions. Rereading this post leaves me wondering if you're not using the factory controller what are you using? How is it plumbed?

On the esoteric side of things there is another piece to this puzzle. As boost builds so does exhaust back-pressure. This pressure is pushing against the WG attempting to open it. The WG spring counteracts this pressure holding the gate closed until desired boost is achieved. Then the controller begins to open, sending boost pressure to the WG over coming spring pressure and the gate begins to open. Hence the reason shortening the rod increases boost all else being equal. It's a balancing act between boost pressure, back pressure, spring pressure (or rate), spring pre-load and controller. Unless you install a different turbo you only have control over the spring (rate and pre-load) and the controller. (IE when and how the controller opens sending pressure to the gate.) Which is why all the controller people sell different springs.

Gotta be careful which "controller" we're talking about. The controller valve or the controller itself which "controls" the actual gate.:roll:

FWIW I run a simple manual controller with solid boost control. Maybe I'm just lucky. Lots of folks don't like manual controllers.

 

[Couger1968]

Re: power after forge wastgate install

No controller at all, only spring tension in the wategate. It hooks directly to where the factory controller got its signal from the turbo. The spring tension on a forge is a lot more than a factory actuator. I suppose my exhaust being mostly stock with a high flow cat could be blowing the wastegate open, but it would take a lot.

 

[Don W.]

Re: power after forge wastgate install

No controller at all, only spring tension in the wategate. It hooks directly to where the factory controller got its signal from the turbo. The spring tension on a forge is a lot more than a factory actuator.

I don't think this is a good way to do it. Every system I've ever looked at (other than on a diesel) has a valve of some sort controlling the controller so-to-speak. This keeps boost pressure off the WG until desired boost is reached then it opens applying pressure to the WG controller opening it and keeping boost at the desire level. This way the spring "pre-load" only has to keep the gate closed against exhaust pressure as I described.

 

[Couger1968]

Re: power after forge wastgate install

That is the way a forge works, it spools like mad, and easily. I have never broke all four loose until I had one. It works well except the dropping of 1 psi. Nothing to go wrong either.

 

[Don W.]

Re: power after forge wastgate install

That is the way a forge works, it spools like mad, and easily. I have never broke all four loose until I had one. It works well except the dropping of 1 psi. Nothing to go wrong either.

Seems odd to me but I'll take your word for it. I looked at their website but couldn't find any plumbing diagrams but they do sell boost controllers.

BTW I leave the line at 2000 with 23# air in the tires. 4-5# boost and still break 'em loose. Thinking of another pair of slicks since the pair I have don't match my fronts well.

 

[Couger1968]

Re: power after forge wastgate install

I have a very mild build and wasn't really trying. I only have about 700 miles on the truck. I was more trying to see where my converter stall was and where I could hold boost. I put a TCI breakaway when I built it. It just surprised me. When I was stock it never did it for me.

 

[Damian]

Re: power after forge wastgate install

That is what I thought. I only have it just holding the wastegate shut. It seemed to me the more preload (shortening of the rod) the worse it gets. I suspect what is happening to me is as I run the air is warming up. I have the wastegate hose on the turbo. The intercooler is cool and the air is 19psi at the turbo and the intake. As i run the air is still 19 at the turbo ,but the intercooler heats up and the air is less dense and starts to drop psi at the intake.The factory electronic got it's signal at the intake so it compensated for it. That is why I was wondering if I got my signal for the wategate after the intercooler it would be more accurate. I wouldn't think after the throttle plates would be good for the turbo without a BOV, so in between the intercooler and throttle body. My intercooler doesn't cool as good as it should. Exaggerating the problem. It can go from 100 to 150 degrees by the end of a run. I think I need to reroute my lines.

The higher temps are because you are starting to push that little stock turbo to its limits.

 

[Couger1968]

Re: power after forge wastgate install

I agree that is why I went with slightly higher stall. I am thinking a 20g and a forge will work with it

 

[dgoodhue]

Re: power after forge wastgate install

BTW The pressure at the turbo is probably 4-5 psi higher than the intake manifold reading when using the stock IC.

Pressure is pressure. It won't make a difference if it is 19 psi cold or hot. Moving the reference from the turbo to manifold will raise the boost higher because of the drop accross the intercooler. Not because of the cooler air temps.

 

[Don W.]

Re: power after forge wastgate install

BTW The pressure at the turbo is probably 4-5 psi higher than the intake manifold reading when using the stock IC.

Pressure is pressure. It won't make a difference if it is 19 psi cold or hot. Moving the reference from the turbo to manifold will raise the boost higher because of the drop accross the intercooler. Not because of the cooler air temps.

With all due respect Dave, at a given pressure, density does change with temp. See:

http://www.engineeringtoolbox.com/air-temperature-pressure-density-d_771.html

I compared 20# "boost" to 70* and 140* (not unheard of without alky). .156 to .177. That's about a 13.4 % or 11.8% change depending on which way you're going.


Maybe that's not much with our motors but there is a difference.