Anyone want to take a stab at this (electronics/relay guru's inside)

[Wicked98Snake]

Gotta say man you seem to know your stuff, good luck getting it worked out. Just reading some of the stuff in here baffles my brain, lol.

[dville_gt]

Gotta say man you seem to know your stuff, good luck getting it worked out. Just reading some of the stuff in here baffles my brain, lol.

not sure if this is laced with sarcasm or not, i'm always learning and efi tuning is new to me, wasn't happy with the tuning i paid for so i decided to buy the tuner suite and take a stab at it. i am no master (nor are many people who claim to be), but i have been able to get my car to a point i am very pleased with. i could just call it quits like it is, as i said earlier this isn't really a problem, i just enjoy tinkering with it and if throwing in a $4 spdt relay and doing some wiring means i can get the tune even better that is what i'll do 100 times out of 100.

the kiss people will also tell you that the pcm doesn't need a speedo signal either, this is also "true", but why hamper the pcm's ability to do it's job well because you are too lazy to shell out a few bucks for a pulse generator which allows you access to the throttle cracker, etc.

i'm sure mike (beenfetched) is going to come back in here and bash me again, it is easier, after all, then actually providing answers the questions that i asked.

wicked98snake, if you were actually being serious i appreciate it, this couple has been a huge learning experience and every time i work on it i try to make it a little better.

[turbostang]

James, this time around I have to agree with Mike, maybe not in tact, but in theory. lol. I know what you are trying to do, and I fully understand your motive, but I think there's easier avenues to fix the problem. Some may say 'hack', but I say 'less work'. I also say that excessive wiring leads to problems. I admire your thoroughness, but sometimes it's just not necessary imho.

I'll start out by saying that where there's a will there's a way - and that I'm not familiar with the GM tuning ability in any form or fashion - but most of those tables are probably designed around drive comfort, idle quality, etc.. all while using STOCK components, like cams, converters, exhaust etc... I'd venture a guess that some of those parameters may not even be able to meet your requirements in the first place due to the camshaft, converter blah blah runnign those parameters WAY out of tolerance...if that makes sense.

If the engine gasps for air when sudden load is applied, I'd investigate giving it more air when the load is applied - maybe porting the iac, maybe relieving the spring, maybe drilling a hole in the throttle body blade, maybe adding iac counts at X load, X rpm, etc.. I bet there's a way to fix it without overcomplicating it with relays. Look at it like this, NONE of the aftermarket ECU's have anything other than IAC control, spark, etc.. and a LOT of them don't even use the IAC.. MUCH bigger cams, heads, exhaust etc.. and they all idle fine on gear changes etc..I guess what I'm getting at is they don't have any gear change relays (for that purpose) and they can be made to idle exactly the same as in park...

[Wicked98Snake]

No I'm serious, I hate working with electrical stuff, props man.

[dville_gt]

James, this time around I have to agree with Mike, maybe not in tact, but in theory. lol. I know what you are trying to do, and I fully understand your motive, but I think there's easier avenues to fix the problem. Some may say 'hack', but I say 'less work'. I also say that excessive wiring leads to problems. I admire your thoroughness, but sometimes it's just not necessary imho.

I'll start out by saying that where there's a will there's a way - and that I'm not familiar with the GM tuning ability in any form or fashion - but most of those tables are probably designed around drive comfort, idle quality, etc.. all while using STOCK components, like cams, converters, exhaust etc... I'd venture a guess that some of those parameters may not even be able to meet your requirements in the first place due to the camshaft, converter blah blah runnign those parameters WAY out of tolerance...if that makes sense.

If the engine gasps for air when sudden load is applied, I'd investigate giving it more air when the load is applied - maybe porting the iac, maybe relieving the spring, maybe drilling a hole in the throttle body blade, maybe adding iac counts at X load, X rpm, etc.. I bet there's a way to fix it without overcomplicating it with relays. Look at it like this, NONE of the aftermarket ECU's have anything other than IAC control, spark, etc.. and a LOT of them don't even use the IAC.. MUCH bigger cams, heads, exhaust etc.. and they all idle fine on gear changes etc..I guess what I'm getting at is they don't have any gear change relays (for that purpose) and they can be made to idle exactly the same as in park...

Brooks, first of all I always appreciate when you chime in on my threads (even if you are disagreeing with me ) Amazing what a little class and politeness can do.

I agree with what both of you are saying, it most definitely can be done, and my car is doing it quite well, it's not that my car idles differently in drive vs. park, it's the transition that I don't like. For example, when I turn my a/c on I can ramp in more idle airflow/timing for the load before it hits, and once I get the hold time and delay correct it seems like the a/c doesn't affect the engine at all, or if anything that it makes the engine spin a little faster/easier. Many folks (especially guys running newer PCM's that require serial a/c request signals will claim that you don't need the PCM to know that the a/c is on and that the IAC will adjust, which is true, but thankfully for me the 04 express van pcm accepts a +12v a/c request and I get to benefit from the added functionality, ie. idle adjust, fan control, compressor cycling via stall saver algorithms, etc.) So it seems like for 4 bucks and 20 minutes worth of time I could have even more control over the idle functions then I currently do.

I've got my IAC counts right where they should be with a cam this size, seeing about 60 IAC counts (out of 300) at operating temp/idle with about .5v at the tps (reading 0%), I have drilled the t/b blade and slotted the tps sensor. There is enough room for the motor to get the additional air it requires. It does a good job as it sits, but it still seems like a comprimise to me, am I over thinking it (dville_gt over thinking something ), probably, but after searching ls1tech and the hptuners forums many others agree that you can get better results if you inform the pcm when you are going to load the engine.

For example, I can't see how the throttle follower could be expected to be the same regardless of if the motor is in a free reving state or a loaded state. Seems like the motor will need to return to adaptive idle controls sooner if it is simply free reving vs. being in gear. Maybe I am wrong, but it'd at least be nice to be able to play with the park/neutral values without fearing messing with my drive values or vice versa. This is why I think it can't hurt and most likely will help with the over all fit and finish of the tune.

[turbostang]

Brooks, first of all I always appreciate when you chime in on my threads (even if you are disagreeing with me ) Amazing what a little class and politeness can do.

I agree with what both of you are saying, it most definitely can be done, and my car is doing it quite well, it's not that my car idles differently in drive vs. park, it's the transition that I don't like. For example, when I turn my a/c on I can ramp in more idle airflow/timing for the load before it hits, and once I get the hold time and delay correct it seems like the a/c doesn't affect the engine at all, or if anything that it makes the engine spin a little faster/easier. Many folks (especially guys running newer PCM's that require serial a/c request signals will claim that you don't need the PCM to know that the a/c is on and that the IAC will adjust, which is true, but thankfully for me the 04 express van pcm accepts a +12v a/c request and I get to benefit from the added functionality, ie. idle adjust, fan control, compressor cycling via stall saver algorithms, etc.) So it seems like for 4 bucks and 20 minutes worth of time I could have even more control over the idle functions then I currently do.

I've got my IAC counts right where they should be with a cam this size, seeing about 60 IAC counts (out of 300) at operating temp/idle with about .5v at the tps (reading 0%), I have drilled the t/b blade and slotted the tps sensor. There is enough room for the motor to get the additional air it requires. It does a good job as it sits, but it still seems like a comprimise to me, am I over thinking it (dville_gt over thinking something ), probably, but after searching ls1tech and the hptuners forums many others agree that you can get better results if you inform the pcm when you are going to load the engine.

For example, I can't see how the throttle follower could be expected to be the same regardless of if the motor is in a free reving state or a loaded state. Seems like the motor will need to return to adaptive idle controls sooner if it is simply free reving vs. being in gear. Maybe I am wrong, but it'd at least be nice to be able to play with the park/neutral values without fearing messing with my drive values or vice versa. This is why I think it can't hurt and most likely will help with the over all fit and finish of the tune.

Well, I'd have to see the values and what's adjustable to make an educated guess - but on aftermarket ECU's there's a 'decay' value associated with things like IAC etc.. The decay is the amount of time that it takes for the ecu to relinquish control over the iac to something like part_throttle_adder table (or something like that). The only problem with things like that is that you have to duplicate EVERYTHING in the tune each time you make an adjustment, or your just pissing in the wind. For example, the biggest thing to duplicate is the coolant temp - all EFI systems have control in regards to coolant temp, like fueling and spark for example..and if the coolant temp is far enough off, it can easily skew your IAC adjustments (or whatever you're working on) long enough to give you false hope in regards of solving your problem.

I'll stick to my guns on this one, I am positive there's a way to solve your problem via tuning instead of wiring up those relays - mainly by treating it as if it's like FAST, BS3 etc... The problem with the relays, I suspect once you enable them - that you will undoubtedly have to tune your ass off anways, and you'll still have to rely on them to work. You can just tune your ass off now, and 98% probability fix your problem without them. (if that makes sense?)

How about disabling the IAC to keep it from oscillating? (is there a way to do that in the software to keep from throwing errors?) This would easily solve the sudden oscillation with widely varing loads. At that point, it would just idle down some - and you could add timing, take away fuel to 'fix' it.

[dville_gt]

I am not arguing the idea that it can be tuned to be fairly uneventful during the load up of the transmission, but, and maybe I am splitting hairs here, you are still limiting the amount of control you have over the PCM and it's ability to provide the best (read: most seamless) transition between load and no load. Here is what one of the HPTuners guys said:

It can be changed/deleted as needed. What year PCM are you running and what kind of trans? If its a red/blue PCM and non electronic trans I would switch it over to a P/N switch when you have the PCM reflashed and hook up a P/N switch to your shifter. Same basic idea if its a blue/green PCM. If you are running an electronic trans I would keep the PRNDL switch, you can actually run without it but it would have to be programmed out of the PCM and the car will have better driveability with it. IE: It will kick the idle up a bit when in drive, there are different spark and airflow tables for drive and park, etc.

Granted I am not running an electronic transmission, but I'd think the same principles would apply as far as driveability.

As for wiring it up, it will be one simple relay that grounds out 2 wires in the non-energized position, and grounds 2 different wires in the energized position, I'll use the neutral safety switch on my quarter stick to activate the relay when the car is in park/neutral.

[turbostang]

I am not arguing the idea that it can be tuned to be fairly uneventful during the load up of the transmission, but, and maybe I am splitting hairs here, you are still limiting the amount of control you have over the PCM and it's ability to provide the best (read: most seamless) transition between load and no load. Here is what one of the HPTuners guys said:



Granted I am not running an electronic transmission, but I'd think the same principles would apply as far as driveability.

As for wiring it up, it will be one simple relay that grounds out 2 wires in the non-energized position, and grounds 2 different wires in the energized position, I'll use the neutral safety switch on my quarter stick to activate the relay when the car is in park/neutral.

You are not limiting the control of the ECU, you're just going to use what's necessary. You are limiting the part that YOU have to mess with to make it work right.

I don't think you can do what you are talking about without using TWO relays.

[dville_gt]

The way I read the schematics, the PCM see's a "Hi" signal by default, the "Low" signal is done via grounding. Thus I believe one SPDT relay would suffice for the wiring.

[turbostang]

doh, reading owns me right now - I didn't see, or even think of a DPDT relay.

[dville_gt]

doh, reading owns me right now - I didn't see, or even think of a DPDT relay.

i'll only need a spdt since i'll be removing ground from 2 wires and putting ground to 2 different wires, single pole (ground).

[Sam88gta1]

You dont need a relay to fix your problem. Most if not all of it can be fixed with timing.

[turbostang]

You dont need a relay to fix your problem. Most if not all of it can be fixed with timing.

..and there you have it, If Sam says it can be done - I'd believe it.