Timing advance and boost - DM vs. plugs

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

intheclouds,
I pulled the boost back out and have backed off all settings, but the wavy boost is still really noticeable. As far as Datamaster, I've had a heck of a time with it. On one laptop (Windows 7), it will not monitor anything except the fields at the top. On an older one (with XP), it was working fine, but now will *only* monitor. Every time I try to start, it just goes into monitor mode. Then when I try to make a run, it locks up for the first 5-7 seconds of the run and doesn't record anything. I haven't bought the full version and am not going to until I can get it to work. On both, I'm still within the free trials.
Eric,
Adjusting the actuator helped with the wgdc, so I'll give it another turn and a half. Once I get that resolved, I may contact you about a chip re-burn. I'd like to know, though, if I would gain anything (or lose anything) by going with a separate controller. I need to order a boost gauge and can get either a normal one from AEM or one with a built-in boost controller and replacement solenoid (their Tru-Boost). If it would just duplicate what the chip is already doing, though, that would be a waste of money. I'd almost rather have everything controlled from the VeloSyTy chip since it works so slick.

 

[randy merritt]

Re: Timing advance and boost - DM vs. plugs

You could try a manual boost controller. Here is a screen shot of an old DM run on my truck. I have a GT35r, so I don't know if your stock turbo will be as solid as mine, but as you can see, my boost is pretty consistent with a manual boost controller.

 

[intheclouds1977]

Re: Timing advance and boost - DM vs. plugs

Wow, that boost looks really good! I was never able to achieve anything like that!

 

[It's just a six]

Re: Timing advance and boost - DM vs. plugs

I like the AEM Tru boost controller I have.

It made the boost more stable & consistent that the stock set-up.

It also helped make my Sy faster.

With the TRU boost controller it will have less boost creep then a manual boost controller (turbo will spool up faster) & it won't change when running at different altitudes, basically much more consistent boost control over a manual valve, they both work, just electronic control is just that much better IMO.:2cents:

 

[Eric Sy GN]

Re: Timing advance and boost - DM vs. plugs

With a stock turbo/no cat, it will still be tough to get it that smooth. I suspect you'll have some spikes on the shift. I admit I've never tried it though.

 

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

So how does the control in the chip compare to a stand-alone ebc like the AEM. Is there a benefit?

 

[Eric Sy GN]

Re: Timing advance and boost - DM vs. plugs

The stand-alones vary. Some are closed loop, some are open loop.

The stock-type ECM control is closed loop. In other words, it monitors boost, and adjusts up or down to keep in a certain range. But it's harder for you to make adjustments to all the settings.

The AEM is open loop and does not monitor boost and make adjustments based on feedback, you are basically just setting the wastegate duty. However, it's easier to tweak it yourself.

Eric

 

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

Ah ha. I assumed all were closed loop and, therefore, the magic was in something like the PID parameters (if you're familiar with feedback controls). That's why I was confused why someone would want an aftermarket electronic boost controller if the same thing could be done on the chip (unless the aftermarket solenoid was somehow better). I would expect that we'd always want a closed loop system, but I guess not??
So if the AEM (and others) are open loop, there's no reason to expect them to help stabilize boost, correct?
In reading, it looks like my repeatedly shortening the wg actuator rod could be contributing to the wavy boost. But it also seems like it needed it some to keep the duty cycle reasonable. How do I find the happy medium?
So many questions, I know. But I really am having a great time learning all this...

 

[It's just a six]

Re: Timing advance and boost - DM vs. plugs

I would suggest to port your waste gate hole larger, the stock size hole is the problem, it is too small.

The Tru boost controller will work better than the factory ECU can.

The factory set-up will have boost creep, it will allow the waste gate valve to crack open sooner there fore making the turbo to spool up slower.

The Tru boost controller is not the best out there, but it is far better at controlling boost & making your turbo spool quicker than what the stock set-up can do.:2cents:

As long as you have tuned your engine for all the different boost settings you are going to run your engine at, the tune will be correct, even in open loop.

Problem when shortening the waste gate rod too much, you will lose the full travel of the waste gate valve, & in doing this, it will only bypass only so much of the exhaust gas.

When you port open your waste gate hole, the valve will not need to open as far & will control the boost pressure easier.

 

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

Ok, so humor me for just a minute. I've spent the last hour researching and it looks like boost control may be an ongoing thing with big exhaust and no cat. So here are the options I've found.
1. 3" "JSM-style" down pipe. Cost: $650 from Sportmachines and a days work.
2. External wastegate. Cost: $200 minimum for gate, plus flange (where to get) plus welding cost plus at least a weekend of work (I work slow...).
3. Port existing wastegate. Cost: procedure is nebulous in my mind, but turbo removal and machine shop work seem to be in order.
4. Put cat in or equivalent restriction.
Does that cover it? I'm curious (just for curiosity's) why the simplest solution isn't just adding a little restriction back? Sure, you're strangling it, but no more so than the thousand trucks with a cat. Could be done in a couple hours for cheap. Just spitballin' since I don't like the other options.

 

[dgoodhue]

Re: Timing advance and boost - DM vs. plugs

Since you are reaching 100% duty cycle, the only way to reduce your boost is to length the rod. The catless exhaust and no muffler are contributing to this. I had a high flow cat & catback exhaust on a stock turbo and it would creep to 16psi in 3rd gear.

Adding backpress (catalytic converter) should help bring the waste gate duty cycle down but I am not sure if the boost control will be solid with turbo tweaks chip. (Nxothing against his chip there are just too many parameter to adjust in the stock ECM files). The factory boost control was never great in the first place.

 

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

Lengthen the rod? I've been shortening it. Which should I do?

 

[It's just a six]

Re: Timing advance and boost - DM vs. plugs

Several years ago, I had sent my turbine housing to Forced Performance & they installed a larger waste gate valve & enlarged the hole for $100.

That would be the easiest thing for you to do.

There are probably guys here on the forum that would sell you a turbine housing, (as not to have much down time) there might be someone that will give you a stock turbine housing?

 

[dgoodhue]

Re: Timing advance and boost - DM vs. plugs

Lengthen the rod? I've been shortening it. Which should I do?

Lengthening the rod lowers the base boost. Shortening the rods raises the boost. You boost is smoothing out because the ECM is commanding solenoid to be open so I running off base boost.

 

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

I'm taking the plunge and started pulling the turbo tonight. I forgot how much I hate working on GM vehicles. I need how many different wrenches?? I think I'm going to port it, but need to do some research. If I do that, though, won't I need a custom downpipe and flange?

 

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

Ok, I was thinking that when you said "port" you meant to remove the plug, but you just mean porting like you'd port match a head, right? Does that do enough? I was all set to machine a flange and weld in a new section to the bottom side of the downpipe...

 

[It's just a six]

Re: Timing advance and boost - DM vs. plugs

I'm taking the plunge and started pulling the turbo tonight. I forgot how much I hate working on GM vehicles. I need how many different wrenches?? I think I'm going to port it, but need to do some research. If I do that, though, won't I need a custom downpipe and flange?

By porting I mean to remove material w/a carbide burr. Enlarging the wastegate hole, it is underneath the wastegate flapper valve.

You can port the wastegate hole, but you need to remove the block off round plug to get to the wastegate hole. It is tack welded in.
Example:


It is also better if you can remove the wastegate valve to gain access easier to the wastegate hole.
Here is the arm for the wastegate valve, you would need to grind down the weld, mark the center w/a center punch, then mark the arm w/a center punch as to reinstall it the same position it came off.



Do some research.
To put it all back together, you need to re-weld the wastegate arm back on & tack weld the round block off plug.

I also port around the inside of the turbine housing where the wastegate flapper valve gets closest to the wall.
Example:

 

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

Wow, great pics. Thanks! So is that the one you sent to Forced Performance or did you do it yourself?
I called Forced Performance and they said they can do the port for $95 and the flapper for $75 with a turn-around time of 3 weeks. If that will get me better boost control, it's worth the money. I'm going to start a new thread in the engine and exhaust forum since this one has meandered quite a bit.
Thanks again for all the great support.

 

[It's just a six]

Re: Timing advance and boost - DM vs. plugs

Wow, great pics. Thanks! So is that the one you sent to Forced Performance or did you do it yourself?
I called Forced Performance and they said they can do the port for $95 and the flapper for $75 with a turn-around time of 3 weeks. If that will get me better boost control, it's worth the money. I'm going to start a new thread in the engine and exhaust forum since this one has meandered quite a bit.
Thanks again for all the great support.

This it the one I sent to Forced Performance. It is a 10 CM turbine housing.

You can see where they installed a sleeve & welded the sleeve in.









I would ask is if they could remove some material on the sides where the valve get close to as the valve opens, unless they think it is not necessary.

One other thing to consider, if you are going to install a larger valve & open up the hole bigger, when doing this mod, the exhaust will also have more surface area trying to force the valve open, & you might need a stiffer wastegate actuator, (which the stock actuator is too soft anyways & actually opens too soon..

I added an adjustable helper spring I also wanted a stiffer wastgate actuator. My actuator has a base boost pressure of 15 psi, meaning if the solenoid is disconnected & my AEM Tru boost is not working, it will give my engine 15 psi.



Installing a stiffer wastgate actuator is highly recommended & really wakes up the performance of your engine.

There are adjustable actuators available .

You might not need a different stiffer actuator, but it would a good part to get in the future.:2cents:

I have done minimal mods to my stock long block engine Syclone, all these little things add up to better performance, better drivability.

Not bragging, last time at the track.(Damm 5 years already! , lets get to drag racing So-Cal peeps!) Slow reaction .Sy was running too lean 13.8 & leaner A/F ratio W.O.T. in the right lane. Running an Ultimate 10-1 chip @ the time.
It runs better now with Code 59.

 

[E.Murray]

Re: Timing advance and boost - DM vs. plugs

What about the Forge billet wg (either instead of or in addition to port)? I contacted SportMachines and he suggesting just doing the Forge and skipping the port work. Opinion?