Chris (Direct QL) Whats going on with your car. Max said you were having trans trouble.

Thanks Scott ;-)
plus OneJay, and motorhead
Scott to answer your question about: ("I'm in for hearing more about how boost pressure is vented. After all, I would think a variable valve (ironically like a wastegate)")
Basically, I am using a wastegate, but on the charge pipe.
1 it is all stainless steal so it polishes up nicely.
2 it can handle allot more heat then I’m gonna put on it
3 it has the dual pressure chambers to allow me to adjust the psi levels, and put vacuum on the top chamber to work as a BOV.
Anytime it would open to vent exhaust gas it would open to vent charge air, but without slowing the turbos as much.
And just like you said, adding wastegates later can be done if it needs be.

 

Bob, thanks for the explanation. All sounds resonable to me.

Good luck with your build!

-scott

 

I think some of you guys missed this post and explanation he gave.

Funny how someone would 2nd guess a Smokey Yunick set up .

Good out of the Box set up thinking .

 

Well, if we're going to nit-pick then I'll repost my earlier question. "How is boost incrementally controlled?" I really didn't get the expanation I was looking for earlier, and I was too lazy to write out my reasons why until now.

Is an electronic boost controller enough to do the job? I would think control of boost is much more sensitive to variations in wastegate valve position given it directly affects boost pressure. The good news is that this method of boost control is probably overdamped (i.e. no overshoot of target boost) because the "plant" doesn't have the lags of a traditional wastegate configuration that has to wait for the boost to respond to changes in exhaust velocity after going through the IC, plenum, and head.

So, is a traditional boost controller enough to get the job done? If not, how do you plan on controlling boost?

Now, that's what I really wanted to know...

Thanks,
-scott

 

wow... why are the harsh replies?

Bob explained it before and I was skeptical as well. The simplest way to describe it. Think of an air compressor. On an air compressor you have a regulator which regulates your air pressure. You can set it to a desired PSI and the regulator bleeds the excess pressure until the set PSI is met.

Im not an expert, but it sounds like it would work to me.

 

Harsh?... huh... I didn't think "nit-pick" was harsh. Oh well... sorry if I offended anyone.

I understand the theory; it's not hard. It's the control I'm interested in. Unlike a BOV that's either on or off, a wastegate is controlled through modulated air past the valve via a solenoid. What's controlling the boost control solenoid and is it plumbed like a conventional boost controller (i.e. bottom of diaphram directly connected to plenum; top valved through solenoid)?

-scott

 

Sorry, I didnt mean you. There were a couple replies a page before from other members that were harsh.

 

It's simple . It's been explained a number of different ways.

 

Scott (motorhead) I don't have any problems with you asking a question, and re-asking if I’m not explaining it where we are understanding each other.
Basically I'm using a wastegate on the charge pipe. I'm installing it with a weak spring, and running full boost to the bottom chamber. Basically very low boost to start. I'm prepared to play with it to get it right. The valve may open and let to much boost out and give a high and low surge. I'm going to have to play with it, but the motor should be able to handle allot more then what I’m going to put on it until I get it working really well.
We used a smaller wastegate on a smaller motor, and it worked great right out of the box. I'm hoping I’m as lucky with the larger wastegate (60mm)

 

Well the fabrication is basically done. I'm sure Chris and I will run into a little thing here and there as I'm sure you guys know the project is never really done.
The front bumper, and nose are back on the car, and Chris is finishing up a couple things with my fuel system. Again I’m running 16 injectors. 8 stock on the stock ECU, and a second set of 8 that add fuel as boost comes on. Chris redid the fuel system on the second set of injectors.
I think the car will be back on the ground and hopefully moving for the first time in 3 years in just a few days.
Here is a photo of my controversial boost control method.

 

Is there a benefit by using 8 extra fuel injectors instead of using only 8 bigger fuel injectors? I think the tuning might be harder and cost may be higher with 8 extra injectors.

 

Good question Steve. Drivability. Lets face it. no tuner is going to tune the car better for drivability then Toyota did with the stock ECU and injectors.
I think tuning is easier as you don't need to tune the car to run. Toyota has that covered. It basically needs to be tuned for the motor under boost only. (I'm not the tuner so I'm really only guessing)
When you go to a large injector you sometimes have a hard time getting the motor to idle, and the lower RPM range suffers. High RPM and racing is great.
The second set of injectors allows me to keep the mild side of the motor with Toyota tuning, and the second set comes on with boost to add the extra fuel.
the additional injector controller cost less then a stand alone, but the additional injector bungs, and the work to put them in basically made up for it.
It's really just a different way of adding fuel.
The system doesn't do timing though, and Chris is working on a unit to retard timing with boost also.
Overall I don't know if it's a benefit or not. it's just another way of getting the fuel in.
It does allow me to run a second fuel through the additional injectors (Alcohol maybe wink wink)

Here is a shot of the second set of injectors plumbed into the monifold.

 

Wow, That is looking awesome Bob!

 

Bob, very pretty!! Chris great fab work!! really looking forward to seeing this baby run!!!

I am really looking forward to see your results on your Wastegated charge air, boost control set up...

I like your custom valve cover plate...

Ryan

 

Thanks Guys, the car is really looking nice.
Chris outdid himself. He has made her much prettier then I was expecting.