12200411 - A Few General Questions

[ezobens]

Dave,
Thanks again for jumping in!

I like the custom reluctor- I saw an outfit on-line called BET Performance that has something similar but the distributor is pricey if all I want this the reluctor.
Perhaps I can inquire if they'd sell just that one part?
Who made the reluctor in your pictures above?

Ok,
So VSS,Oil PSI and Clutch Switch don't appear mandatory or advantageous for my application.
What function does the Brake Switch serve?

Any reason why you would use the Resonant vs Flat Response Knock Sensor?
I'm concerned that my engine might false trigger the Resonant style sensor more often than not (mechanical flat tappet cam and roller rocker noise).
Thoughts?

Thanks again!
Elm

[mecanicman]

While a vss can be eliminated, its much better to run it. You can add a dakota digital vss that goes between your trans and speedo cable. Not using loses you resolution on your timing table and makes idle a little more interesting. The $40 it takes to add it is worth it in my opinion.

[ezobens]

I'm curious (and sorry of this is a dumb question) but how does a 'Speed' sensor help at idle since the car is stationary at idle?
Just trying to understand.
Thanks!
Elm

[EagleMark]

While a vss can be eliminated, its much better to run it. You can add a dakota digital vss that goes between your trans and speedo cable. Not using loses you resolution on your timing table and makes idle a little more interesting. The $40 it takes to add it is worth it in my opinion.

X2!

I've done several differant EFI systems without VSS and some were a lot of tuning work! Then add VSS and they all ran better, even if you don't need accurate speed, just the ECM/PCM knowing the vehicle is moving or not makes Idle so much better. Amongst other things!

Also done a lot of differant motors with TBI injection and made a small cap EFI distributor for every one. Jeep, Ford, Chrysler, etc...

http://www.gearhead-efi.com/Fuel-Inj...BI-Conversions!

[mecanicman]

Its transitions between moving and idle, the computer has different strategies. If you never have a vss, the computer bases all "decisions" on you sitting still. It can be compensated for by putting more air into running airflow table then you normally would.

[ezobens]

Its transitions between moving and idle, the computer has different strategies. If you never have a vss, the computer bases all "decisions" on you sitting still. It can be compensated for by putting more air into running airflow table then you normally would.

Sounds like the VSS may be something I need to consider-
Does the clutch switch play any role with this idle strategy as well?
Thanks!
Elm

[mecanicman]

Sounds like the VSS may be something I need to consider-
Does the clutch switch play any role with this idle strategy as well?
Thanks!
Elm

Yes, but it is easiar to tune around in my opinion.

[EagleMark]

What role does clutch signal play? Isn't it needed for Case Relearn? Or was that Parking Brake on manuals?

[ezobens]

X2!

I've done several differant EFI systems without VSS and some were a lot of tuning work! Then add VSS and they all ran better, even if you don't need accurate speed, just the ECM/PCM knowing the vehicle is moving or not makes Idle so much better. Amongst other things!

Also done a lot of differant motors with TBI injection and made a small cap EFI distributor for every one. Jeep, Ford, Chrysler, etc...

http://www.gearhead-efi.com/Fuel-Inj...BI-Conversions!

I've seen this post and it's very ingenious- Unfortunately, I don't think I can utilize the 2 piece shaft arrangement in my application due to the mechanical tach drive and the cam plate assembly required to attach the points style rotor. I think my best bet will be to alter the cam plate to allow me to attach the reluctor securely.
Luckily, I have a lot of spare OEM points distributors laying around that I can butcher (err- "Engineer") and try to make something that works.
The biggest machining operation would be to the notch the main body so I could attach the OEM CMP sensor without having to notch distributor caps.
Thanks for the ideas!
Elm

[Buzz]

Any reason why you would use the Resonant vs Flat Response Knock Sensor?
I'm concerned that my engine might false trigger the Resonant style sensor more often than not (mechanical flat tappet cam and roller rocker noise).

With the 0411 PCM the L31 Vortec engines (Express / Savana) were equipped with Resonant style knock sensors, just like the LSx engines were. There are no OEM defined tables / settings for Flat Response style knocks sensors with these engines using a PCM (0411).

If you conduct an internet search regarding operating an LS2 engine with a PCM, you will read for hours about all of the impasses to attempting to correctly integrate Flat Response knock sensors and a PCM (0411).

Some have tried (and failed) to use the knock sensor settings from a 4.3L V6 using Flat Response knock sensors and a PCM (0411).

Their are couple of companies who offer a wiring harness and PCM that will supposedly achieve this - they don't work. These are typically sold as LS2 conversion kits. Anyone using one of these setups has no knock protection.

Most people who have swapped in a 24x CKP LS2 have mounted the Resonant style knock sensors.

[ezobens]

With the 0411 PCM the L31 Vortec engines (Express / Savana) were equipped with Resonant style knock sensors, just like the LSx engines were. There are no OEM defined tables / settings for Flat Response style knocks sensors with these engines using a PCM (0411).

If you conduct an internet search regarding operating an LS2 engine with a PCM, you will read for hours about all of the impasses to attempting to correctly integrate Flat Response knock sensors and a PCM (0411).

Some have tried (and failed) to use the knock sensor settings from a 4.3L V6 using Flat Response knock sensors and a PCM (0411).

Their are couple of companies who offer a wiring harness and PCM that will supposedly achieve this - they don't work. These are typically sold as LS2 conversion kits. Anyone using one of these setups has no knock protection.

Most people who have swapped in a 24x CKP LS2 have mounted the Resonant style knock sensors.

OK-
I was following the path of since the the 4.3L Vortec used the Flat Response Sensors with the 12200411 PCM, why couldn't I just overwrite the 5.7L Knock code with the 4.3L? Seems from the outside that this wouldn't be hard to do but then I have ZERO experience playing with any code within these controllers.
Bummer, on paper it sounds like this would be a fairly easy switch but it sounds like not so much.
Thanks!
Elm