Slight pinging

[egk2]

I get slight pinging even with 94 ultra gas with a JC chip, what to do?
Stock chip?
Thanks

[bmwdude]

Ok. I've been there myself, so I know how you feel. Before we go into more depth here, and my forwarding you, last ditch info(that will work), on timing retard, etc, lets see if the basics haven't been overlooked.

Did the car start to ping AS SOON as you installed the JC chip?

You will hate this question(1st one), but I will ask it nevertheless.

-When is the last time you did a tune up?
-When was the last time the rotor and cap were replaced and/or visually inspected?
-Last time you changed your plugs?
-Have you checked your fuel pressure for confirmation while on load??

Is your car pinging at full throttle or partial? Both?

Also, in the meantime, should and if the above list checks out for you, add a bottle of good quality fuel system cleaner, and drive your car hard for a while.

I'm very curious how all this turns out!

[egk2]

I've always had the JC chip with stock M20 and now with the stroker.
Everything is new since swap.
I have not checked fuel pressure under load.
Car pings slightly WOT and partial.
I remember someone with the same issues and the stock chip was put back in to resolve it.

Ok. I've been there myself, so I know how you feel. Before we go into more depth here, and my forwarding you, last ditch info(that will work), on timing retard, etc, lets see if the basics haven't been overlooked.

Did the car start to ping AS SOON as you installed the JC chip?

You will hate this question(1st one), but I will ask it nevertheless.

-When is the last time you did a tune up?
-When was the last time the rotor and cap were replaced and/or visually inspected?
-Last time you changed your plugs?
-Have you checked your fuel pressure for confirmation while on load??

Is your car pinging at full throttle or partial? Both?

Also, in the meantime, should and if the above list checks out for you, add a bottle of good quality fuel system cleaner, and drive your car hard for a while.

I'm very curious how all this turns out!

[bmwdude]

Perhps I was one of those guys with those issues? ;)

Chances are then that your JC chip is not mapped right for your stroker. My stroker also did not run that good with the JC chip. I ran it for not even a day, then took it out immediately!

Stroking an engine is not the smallest of modifications one can make you know......

Remapping a chip accordingly would make sense. Installing a JC chip, designed for your average 2.5L would not.

If you still find that you are having pinging issues however, once you install your stock chip, let me know.

Good luck!

[egk2]

I'm going to pick up a stock chip and give that a try for now, custom chip will come later.

[Jordan]

What c/r are you running? anything over 9.5:1 isnt going to work with a JimC chip. Far too much timing advance for us.

Go back to a stock chip, and get a custom tuned piggyback unit to get the full potential out of the engine. Not some off the shelf chip made for a 2.5.

[egk2]

10:1, all I have is the JC chip, I'm actually picking up a stock chip from Alex, this will have to do for the time being. Thanks

[pig4bill]

Ok. I've been there myself, so I know how you feel. Before we go into more depth here, and my forwarding you, last ditch info(that will work), on timing retard, etc, lets see if the basics haven't been overlooked.

My stroker pings too. I wouldn't mind getting the timing retard info. I have a stock chip.

-Have you checked your fuel pressure for confirmation while on load??

How does one do this? Buy a fuel pressure guage intended for the cockpit?

Also, in the meantime, should and if the above list checks out for you, add a bottle of good quality fuel system cleaner, and drive your car hard for a while.

My 19# injectors are new. Driving the car hard is somewhat of a problem, because that's when it pings. :)

[bmwdude]

Ok. I've been there myself, so I know how you feel. Before we go into more depth here, and my forwarding you, last ditch info(that will work), on timing retard, etc, lets see if the basics haven't been overlooked.

My stroker pings too. I wouldn't mind getting the timing retard info. I have a stock chip.

-Have you checked your fuel pressure for confirmation while on load??

How does one do this? Buy a fuel pressure guage intended for the cockpit?

Also, in the meantime, should and if the above list checks out for you, add a bottle of good quality fuel system cleaner, and drive your car hard for a while.

My 19# injectors are new. Driving the car hard is somewhat of a problem, because that's when it pings. :)

More than happy to oblige! Before I go on, PLEASE make sure that your basics like wires, plugs, etc are in order, and that your car is not pinging because of some sort of maintenance issue. I'll give you a quick summary here(as I can't remember the small details that were involved because it's late as I write this....and I apologize if my terminology is bad), but I'm very anxious to try and help you, and see if this proves to be a success for you ;) . It's actually very simple.

Concetrate your attention to the crank sensor in the front, and down low of your engine. It is held in place by a bracket of some sort. If I recall correctly, it is held in place by two bolts. You need to make one of the holes on the bracket slightly larger (and I REALLY apologize that I can't remember the specifics, as it has been a while, but I'd be more than happy to go look at my car tomorrow after work), so that you will be able to slide the sensor up or down. AGAIN, if I recall correctly, when I moved the sensor upwards by 1-2mm, it retarded the timing. I believe that a 1-2mm movement will retard the timing by about 3-5 degrees. Moving the sensor in the opposite direction will have the opposite effect.

This method proved 100% effective for me! In fact, it was after this breakthrough, that I went ahead and turbocharged my 3.0L.

Once you have gone down there, and observed things yourself, you'll get the idea. You can also take the car to a BMW tech, or any other good German specialist, and explain to them what I just wrote you. They should be able to do this 30 minute "custom" job.

A fuel pressure gauge for the cockpit is always a nice addition, especially for a turbo car! What I did have in mind however, was you or your mechanic, taping a fuel pressure guage on the outside of your windshield, and going for a spin around the block. If you don't do your own work, and have to pay someone, what will this cost you? 20 minutes of labour? It's good to get the fuel pressure confirmed and out of the way.

To conclude, make sure that you have checked EVERYTHING before deciding to retard the timing. Retarding the timing on a car that is pinging for other reasons, may actually still reasult in ridding of it, but you will have lost some power and economy for nothing. If everything in your stroker is indeed new, sensors, wires, cap, rotor, fuel pressure checked, etc, then this method is the way forward to a wonderfully tuned stroker engine.

Good luck!

[pig4bill]

Ok. I've been there myself, so I know how you feel. Before we go into more depth here, and my forwarding you, last ditch info(that will work), on timing retard, etc, lets see if the basics haven't been overlooked.

My stroker pings too. I wouldn't mind getting the timing retard info. I have a stock chip.

-Have you checked your fuel pressure for confirmation while on load??

How does one do this? Buy a fuel pressure guage intended for the cockpit?

Also, in the meantime, should and if the above list checks out for you, add a bottle of good quality fuel system cleaner, and drive your car hard for a while.

My 19# injectors are new. Driving the car hard is somewhat of a problem, because that's when it pings. :)

More than happy to oblige! Before I go on, PLEASE make sure that your basics like wires, plugs, etc are in order, and that your car is not pinging because of some sort of maintenance issue. I'll give you a quick summary here(as I can't remember the small details that were involved because it's late as I write this....and I apologize if my terminology is bad), but I'm very anxious to try and help you, and see if this proves to be a success for you ;) . It's actually very simple.

Concetrate your attention to the crank sensor in the front, and down low of your engine. It is held in place by a bracket of some sort. If I recall correctly, it is held in place by two bolts. You need to make one of the holes on the bracket slightly larger (and I REALLY apologize that I can't remember the specifics, as it has been a while, but I'd be more than happy to go look at my car tomorrow after work), so that you will be able to slide the sensor up or down. AGAIN, if I recall correctly, when I moved the sensor upwards by 1-2mm, it retarded the timing. I believe that a 1-2mm movement will retard the timing by about 3-5 degrees. Moving the sensor in the opposite direction will have the opposite effect.

This method proved 100% effective for me! In fact, it was after this breakthrough, that I went ahead and turbocharged my 3.0L.

Once you have gone down there, and observed things yourself, you'll get the idea. You can also take the car to a BMW tech, or any other good German specialist, and explain to them what I just wrote you. They should be able to do this 30 minute "custom" job.

A fuel pressure gauge for the cockpit is always a nice addition, especially for a turbo car! What I did have in mind however, was you or your mechanic, taping a fuel pressure guage on the outside of your windshield, and going for a spin around the block. If you don't do your own work, and have to pay someone, what will this cost you? 20 minutes of labour? It's good to get the fuel pressure confirmed and out of the way.

To conclude, make sure that you have checked EVERYTHING before deciding to retard the timing. Retarding the timing on a car that is pinging for other reasons, may actually still reasult in ridding of it, but you will have lost some power and economy for nothing. If everything in your stroker is indeed new, sensors, wires, cap, rotor, fuel pressure checked, etc, then this method is the way forward to a wonderfully tuned stroker engine.

Good luck!

Thanks for the info. I've been suspicious that I might not be getting full fuel pressure because it seems to run so lean, even with 19 pounders. The local auto parts store has fairly cheap fuel pressure testers but it never occurred to me to set up a rig like that. It should be fairly easy because the tester just comes with a T so I can make the fuel lines as long as I want, and the hood closes from the front to make it even easier.

I want to do as much of this fiddling myself as I can because around here, there's no such thing as "20 minutes labor". It's 1 hour minimum to do anything, at $100+ per hour. It won't take much tuning experimentation for a shop to end up charging me more than I paid for the car.

[bmwdude]

On the topic of fueling, and the PERFECT compliment to the above way of verifying fuel pressure, a wideband oxygen sensor with guage couldn't hurt? ;)