Max safe boost? [Merged 10-6]

[Turbolaser]

Is it safe to do the boost contol solenoid mod on a stock 1G?

 

[91stocker]

You also want to watch IDC % as well.

Good call, i should have mentioned that

He should have some room to play with with those 750's on a 16g, i think thats why it slipped my mind . Edited my previous post

 

[gophishy10]

Ok thanks! I was looking for a general number to go off of. I think I'll have one setting on about 15-16psi and another on around 22. I understand watching for knock, but how much is too much? And also, what is IDC%? My afr's are usually right around 12 during a pull with my setting on 15psi.

Edit: Ok I know what IDC% is now. Does link monitor this? Or do I need to figure this out on my own. I like to be safe so I really don't want to go about 80%.

 

[snowborder714]

Yes, link can capture this. As long as it's in your captured/displayed values, you should be able to see this percentage.

As for knock, I prefer to tune for 0 (with small .4 or .7 spikes if necessary), but some people are happy with anything under 2 or 3. All up to what you want to see.

Are you running that 12:1 AFR on E85? If not, that's a bit too lean for pump gas IMO. You should target 11:1 to 11.5:1, depending on how all the other values look.

 

[91stocker]

I understand watching for knock, but how much is too much?

When you break something, then its too much . Aim for 0, if your seeing more then say 2* then the tune needs some work.

And also, what is IDC%?

Injector duty cycle. You run out of fuel at 100%, the injector just stays wide open. 80% is the typical goal to avoid tuning issues and to improve the life of the injectors.

My afr's are usually right around 12 during a pull with my setting on 15psi.

Thats pretty lean for pump gas. You should aim for 11.5 - 11.7ish range while in boost.


Edit: Dang beat me to it ^^^

 

[gophishy10]

Yes I'm on pump gas. When cruising, I'm almost perfect at 14.7, but during a pull it goes richer to about 12-12.5. Also, I will most likely tune for zero knock. On this point, I've heard many different things. Some people say to turn up boost until you see knock and then turn it down until you don't. But then other people say to adjust timing to get rid of knock. If you can just adjust the timing, isn't there almost not a limit on boost until you max out your fuel mods? Last question is when adjusting timing to rid of knock, do you use the "timing" tab on ECU Config or do I use the "TmngMinOct" table on direct access (which is what the ecmlink demo videos show and I've used this before I installed 16g to rid of knock)?

I'll post a log of settings on 15 and 20psi later.

 

[snowborder714]

You need to richen that up to 11:1 for now. That lean is just dangerous and asking for knock on pump gas.

The way I tune is to set the boost level to what I (or the other person) wants to see. Then get AFR in check via MaxOct DA table and MAF Comp sliders or SD cells. Then work on increasing timing until you see knock and back it down. If you have issues with fuel/timing at that boost level, or see your IDC's are too high, then you know you need to back the boost down a bit.

Correct on boost being limited to just fuel if you have timing adjustment. However, if you're removing so much timing that you're running a few degrees at WOT, then it would probably be better to drop the boost to regain some of that timing. It's a give and take between boost and timing as they both add power.

I suggest strictly using tables. The only time I'd suggest using the timing sliders is when you're trying to figure out if some knock you're seeing is real, in which you can go drop the sliders in that RPM how many degrees of knock you're seeing and quickly do another pull. If the knock goes away, it was real and the timing table needs adjusted. If not, then it was phantom or something else.

 

[gophishy10]

Ok that makes sense. Thanks for clearing that all up. Basically I want as much timing as I can get without getting knock at a specific boost level? I think I want to shoot for 22psi with zero knock if I can. I'll definitely richen it up when I pull. I'll work on that and then post some logs and see what you guys think. I'm pretty comfortable using the DA table to adjust timing.
One other thing...where can you monitor IDC% in link? I have it as a captured value. Is it just a displayed value that I need to check?

 

[snowborder714]

Exactly.

Yes, it'll display below the graph just like any other value you log. Just make sure it's in the list to display.

Sounds good. Make sure to start a new thread in the appropriate forum once you have logs.

 

[gophishy10]

Will do thanks for all the help!

 

[Red 1g talon]

my 1g talon has no problems beside fuel cut at about 6,000 rpm. small 16g pulls alot harder than stock. thats with a wally 255lph and stock 450cc injectors stock fpr also.

 

[keithcfisher29]

I also run 22psi on pump gas with stock head gasket and studs with no problems

 

[gophishy10]

So I haven't really had the chance to tune yet after I posted last. However, I've been reading a lot more. A lot of people are saying that even 20 psi is too much for pump gas. But if you tune to get rid of knock, is this still true? Should I limit the boost level if I'm just on 93 octane?

 

[snowborder714]

The main things you want to look for are (as mentioned before):
Are AFR's in check?
Is there any knock?
Are your IDC's under the recommended value?


If your answers are "Yes, No, Yes", then you can run whatever boost you're at.

Reading will get you no where as all cars are different and all tunes are different. Set the boost, start tuning, and then answer the above questions. Then adjust from there.

 

[gophishy10]

Thanks for the reply. Sorry if I'm beating this death, I'm just trying to understand it fully. And is what everyone refers to as "pump gas" 93 octane or regular 89?

 

[snowborder714]

If they know anything about a turbo car, 93

 

[Diamond Star Werks]

So I haven't really had the chance to tune yet after I posted last. However, I've been reading a lot more. A lot of people are saying that even 20 psi is too much for pump gas. But if you tune to get rid of knock, is this still true? Should I limit the boost level if I'm just on 93 octane?

I haven't seen knock at that boost level yet. Factory tune. About 17* wot timing. I run 18-19lbs.

 

[paularenss]

mbc are really cheap as well.. crank up the boost a bit and see how it takes it

 

[99ECLIPSEGSXDSM]

mbc are really cheap as well.. crank up the boost a bit and see how it takes it

Personally I would not "crank it up and see how it takes it". I would slowly raise it and keep an eye on my logs to see if there's room to grow.

 

[gophishy10]

If we get any more nice days here, I'm going to tune some. I have the apexi AVCR for boost control so it's really easy to control the boost level. I'm going to turn it up slowly and watch for knock. I want to be at 22.

 

[aajj1987]

this is why I need a wideband... I know I need more fuel but gotta have the wideband first it just don't feel safe

 

[Lofty]

I'm on 28 psi on pump with more room to go still.


Dynoed at 300tq 296AWHP.

http://www.youtube.com/watch?v=S-lDCaFsGMc

It's a good time.

 

[gophishy10]

I'm on 28 psi on pump with more room to go still.


Dynoed at 300tq 296AWHP.

Galant VR4 25psi in the rain - YouTube

It's a good time.

28?!? With no knock? I've hit 22 with no knock but it was on accident. I was only aiming for 18. Unfortunately I think tuning any more is going to have to wait till spring now. It's getting way too cold here. Sick video btw!

 

[99ECLIPSEGSXDSM]

28!?! That's crazy.

 

[e85_4g63]

Still wanting to see a Link log showing IDC's with the small 16g at 12 psi (6500 rpm and above at least).

 

[Tyeler18]

I'm waiting on my evo ECU, after that comes in I'll do a 3rd gear pull at 37 psi, and at 43.5psi base pressure.