Timing advance and boost - DM vs. plugs

E.Murray

Donating Member
I just bought Ty #0776 from another forum member. He did all of the usual reliability things to it (vacuum hoses, 3 bar MAP, motor mounts, EGR delete, etc.) and tuned it (VeloSyTy chip) last December when the outside temp was below freezing. Tuned using 93 octane pump gas. It's 95 degrees here now, so I expected it to need some tweaking.
The truck is stock (except for chip and stock turbo with SportMachines impeller). I took it out for the first time and seem to be having issues. There's 0 KR, but the boost is bouncing all over the place (hitting over 17 psi). The truck is also slow (14.9 sec quarter according to the DM file). My assumption, based on the DM file, was that the boost needed to come down a bit and timing needed to advance some. I've been reading about how to read plugs, so I pulled one to see if I could learn anything. It appears that the line on the ground strap is showing too much advance, though, instead of too little.
I haven't used the photobucket method before, so I hope the pics come through.
Looking for any ideas or suggestions. I've spent many hours reading on this forum and have already learned lots. Thanks in advance.
Eric





 

TrendSetter

Organ donor in training
Re: Timing advance and boost - DM vs. plugs

Its been a long time since my SBC days, but i have always considered extended tip plugs a no-no. for some reason in the ls world most people use them. i still stick to shortest electrodes and tips i can, especially on a head as detonation prone as lb4 and l35s.

what heat range are your plugs?

heres a trick i used to do when i was trying to burn down my 3tc, it makes reading the porcelain much much easier.
http://images.couldbeworse.org/toyplug.jpg

here is a really good thread to skim through when you have time
http://www.yellowbullet.com/forum/showthread.php?t=887370
 

Jimmy

Banned
Re: Timing advance and boost - DM vs. plugs

Here's the first thing you do: don't go wide open throttle just yet. You need to ensure that everything is properly set up before you decide to test your engines limits.

So let's start with the basics what injectors does it have,and what is the base fuel pressure set at? Do you have a boost gauge? What is the vacuum at idle? What plugs are in it and what's the gap? Does your intercooler pump work?

We can figure out more after you answer these questions.And probably a bunch of other questions.
 

gringo76

New member
Re: Timing advance and boost - DM vs. plugs

injector duty cycle at 116. no expert but seems like you might need a bigger set of injectors
 

E.Murray

Donating Member
Re: Timing advance and boost - DM vs. plugs

Jimmy,
Stock injectors, no AFPR, no boost gauge (stock truck except for the things mentioned in the top post). Plugs are NGK UR6 and gap is between .035 and .040. How can I see if the IC pump is working? The PO put a hotwire kit and Shurflo (??) in.

Beaner,
The injector duty cycle jumped out at me, too. I asked the PO about it and he said it was always like that. The duty cycle is a calculated thing so, according to something I read here, values over 100 aren't the end of the world. I was considering a fuel pump upgrade. Wouldn't that give me the flow I need so the injectors wouldn't have to kill themselves?

Thanks for the responses.
 

TrendSetter

Organ donor in training
Re: Timing advance and boost - DM vs. plugs

The duty cycle is a calculated thing so, according to something I read here, values over 100 aren't the end of the world.
its not calculated like iat or map, its how long the ecm turns on the injector vs time its off. so 100 and up is static on, so it very well could be the end of your motor.
its probably ok here and there, i ran 130ish idcs without hurting anything but its only split second and I immediately upgraded injectors.
 

wildphil

I Love My Ty's
Re: Timing advance and boost - DM vs. plugs

You need to do what Jimmy suggest.
Find a gauge you can connect to the port in your fuel rail or install a fuel pressure gauge. If it has a stock fuel pump I would replace it with a better one. And I would install a adjustable fuel pressure regulator.

Take the cap off your upper intercooler and see if the coolant is circulating. Your intake air temp. is a little high.
 

dgoodhue

BuSTeD 4.3
Re: Timing advance and boost - DM vs. plugs

The stock injectors can easily be maxed out. I would make sure it has an upgraded fuel pump and look into a adjustable fuel pressure regulator (to increase your FP)

11 degrees is pretty low timing (stock is 14 degrees). Your boost control looks like crap (The stock boost often overshoot and undershoot the target but yours is worse than I have seen). It looks like boost is set for 13.7psi; could your initial wastegate DC setting be set too high causing the roller coaster control?
 

Eric Sy GN

Donating Member
Re: Timing advance and boost - DM vs. plugs

If you could post that log, or email it to me, and also the chip#, I can see how it was set up. The chip # is on the chip label.
Eric
 

E.Murray

Donating Member
Re: Timing advance and boost - DM vs. plugs

Lots of great stuff. Thanks. I'll order the Walbro pump and an AFPR today. Can I stick with stock injectors (for the moment to save some cash)? I don't have big plans for it, other than driving to work on nice days.
As far as the IC goes, I pulled the cap and the level was low (could see just a little in the bottom). I topped it up. I can pull the cap off the upper IC with the truck running and not just make a mess?
As far as the chip goes, I'll get the number tonight when I get home. I'm not driving it until I get everything sorted. Thanks again for all the help.
Eric
 

intheclouds1977

New member
Re: Timing advance and boost - DM vs. plugs

Eric, strange that the IC reservoir was low, I topped that off when I replaced the pump in December...must be a leak somewhere. I never saw any drips in the garage though...very strange. Get that topped off and it may go a long way toward fixing the problem. Bleeding the system is a huge PITA...good luck! It will air lock and you won't feel flow in the reservoir.

As we discussed, the way things are tuned now, boost was nice and steady (when it was zero degrees outside). Maybe adjustments are needed because of the warmer temps...maybe you just need coolant in your IC reservoir. I'd start with adding coolant, then backing the boost off .5 pounds and play around with the WG DC.

Throwing a pump/FPR at it is shooting in the dark. Just because your DC is maxed on your injectors doesn't mean you're going lean (they ran this way stock). Would be best to throw a WB02 at it first, or go to a dyno and run it with their WB02...after your DM graph looks better of course. If you see some lean conditions, then I'd throw more fuel at it (pump/FPR). I see no evidence of detonation on your plugs and from previous data file, you had minimal KR, so I wouldn't jump to a "lean" conclusion. Reminder that the VeloSyTy can be wired with a WB02 for better fuel control.

Eric Sy Gn above is the maker of the VeloSyTy chip. Definitely send him a log, he can be a ton of help. Send him a log after you get your IC working.

The IC pump is hotwired. You should be able to hear it pump with the key on, engine off. It's located behind the bumper on the driver's side.

Timing on the balancer is set to stock specs (0° if I remember right). When I got the Ty, it was advanced about 4-6° farther than it is right now and had excessive knock (around 10-15°)!!! I doubt you'll get good results advancing the distributor any.

Glad you're having fun with her! :)
 
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E.Murray

Donating Member
Re: Timing advance and boost - DM vs. plugs

I have an Innovate LM-1 wideband O2 that I use for ATV tuning. What's the best way to do a quick couple runs with it to check my a/f ratio? Is it OK to just install it in place of the stock one and tell the chip to stay open loop or will that mess with things and give me a false reading? Or is it simple to wire it in and then change back? I'd rather not leave it on the truck, so I just want a way to install it temporarily without a bunch of welding or re-wiring. I agree that would tell us more than looking at injector dc.
Good to hear you're still out there, Brian.
 

intheclouds1977

New member
Re: Timing advance and boost - DM vs. plugs

Can you shove it up the tailpipe on a long rod? I'd guess it needs to be grounded. Best bet would be to get a weld in bung, drill a hole in the exhaust and weld the bung in. Install the sensor. When you're done, put a plug in the bung.

There's instructions in the VeloSyTy manual in the glove box for how to wire the WB02 up to the PCM.

Removing the stock O2 and running in open loop would give different results than in closed loop. If you intend to drive around in closed loop, you should test things the same way.
 

E.Murray

Donating Member
Re: Timing advance and boost - DM vs. plugs

Yeah, I do the "clip it to the tailpipe" thing on ATVs, but I didn't know if that was an accepted method on these trucks. I know the best way is to order a bung and plug, then cut and weld. But if I can do it in 15 minutes tonight instead of waiting a week then spending an hour, that would be preferable. I guess my main question is if it's simple to wire in then undo it or if I need to cut and weld (assuming everybody hates the tailpipe method).
I guess a benefit to the wiring thing is that it's in the data file instead of just on the LM-1 display...
 

intheclouds1977

New member
Re: Timing advance and boost - DM vs. plugs

You could start with clipping it on and just looking at the display. Depending on what you see, you may decide you want to hard wire it and let the VeloSyTy do its thing, or you may even want to permantly install a WB02.
 

E.Murray

Donating Member
Re: Timing advance and boost - DM vs. plugs

Can someone explain how the low IC level could cause the overboost and oscillation? I would expect it to just not cool the air as much, meaning a less dense charge and, therefore, less boost. Is there a mechanism I'm missing? I could understand it causing detonation, but I didn't see any of that. Just looking for some help on the theory.
Also, is there agreement that I can hold off on the fuel pump (for now, at least)? Funds are limited, so I want to use them strategically...
I'll try to get a fuel pressure reading in the next day or two.
 

intheclouds1977

New member
Re: Timing advance and boost - DM vs. plugs

Can someone explain how the low IC level could cause the overboost and oscillation?

I don't know, doesn't make sense. However, everything was running great in December. Assuming nothing went wrong, the only changes I know of are: 1) Low IC coolant level, 2) higher outside temperature. Knowing the vehicle ran perfectly recently, until proven wrong, I'd base all my troubleshooting around these 2 variables.
 

sytyguy

Moderated User
Re: Timing advance and boost - DM vs. plugs

Can someone explain how the low IC level could cause the overboost and oscillation? I would expect it to just not cool the air as much, meaning a less dense charge and, therefore, less boost. Is there a mechanism I'm missing? I could understand it causing detonation, but I didn't see any of that. Just looking for some help on the theory.
Also, is there agreement that I can hold off on the fuel pump (for now, at least)? Funds are limited, so I want to use them strategically...
I'll try to get a fuel pressure reading in the next day or two.

We have fueling and timing tables based on MAT temps (F3, F31M, etc...), so if the charge temp gets high enough the system will automatically adjust timing and fueling to suit the higher temp. Our ECM's reaction to MAT temps is not as thorough or intelligent as would be desired, but it does have a reaction. Air density will dictate a leaner mixture while higher temps will dictate lower timing. These two combined have an effect on power and, therefore, boost control. More than likely you have other issues contributing to boost control, but the suggestion to verify IC level is valid as you want all systems satisfactory.
 

dgoodhue

BuSTeD 4.3
Re: Timing advance and boost - DM vs. plugs

The low coolant should not have much of an effect on the boost control. The low coolant is why the air intake temps are 160 degrees and contributing to slow 1/4 mile times.
 

intheclouds1977

New member
Re: Timing advance and boost - DM vs. plugs

Here's how it ran in December. Troubleshoot what changed first. Ran like a top:

Datamaster%20picture.jpg


DM File: http://www.intheclouds1977.com/Typhoon/Datamaster
 
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