The Cormaro......

[Jim Nilsen]

Originally Posted by David Pozzi

Jim,
I'm so glad to see you posting about tuning instead of about welding!

Just an FYI. The One Lap Camaro has the MEFI4B system, Wideband was added, but even though the ECM can use the signal you have to add another MFR's add on box same as you are doing to run the heater and produce a signal the ECM can read.

Anyway, we were having terrible trouble with the TPS signal when trying to dyno tune the system, even with engine stopped, key on, the TPS voltage was jumping around and the dyno operator said he couldn't tune it that way.

What we found was the Wideband controller was grounded to the same point as the ECM and it was causing the ECM ground voltage to be biased up and down like crazy.

I would try and ground your wideband somewhere else just in case.
David

Thanks for the tip. I have already had enough troubles with the system and just when I get it going I surely don't need to go right back into more problems.

It's more fun to tune than to weld too. The sound of a running car has been a long time coming. I have to weld in the new O2 bung though ,so there we go back to welding,lol Fortunately I am replacing my collector reducers for better flow and gasket seal so I can do both jobs at once.

Are you coming to the Motorstate Challenge again this year? The ride in Penny was GREAT FUN and it is always nice to talk about everything with you.

[Efi69Cam]

Originally Posted by Jim Nilsen

Thanks for the tip. I have already had enough troubles with the system and just when I get it going I surely don't need to go right back into more problems.

It's more fun to tune than to weld too. The sound of a running car has been a long time coming. I have to weld in the new O2 bung though ,so there we go back to welding,lol Fortunately I am replacing my collector reducers for better flow and gasket seal so I can do both jobs at once.

Are you coming to the Motorstate Challenge again this year? The ride in Penny was GREAT FUN and it is always nice to talk about everything with you.

On the DFI wideband controller, if you have the new one that uses the NGK sensors (looks like a mini-me of the Gen 7) the only reason to use the speed sensor input is if you want a speed dependent control or for the data-logging functions.

[Jim Nilsen]

Originally Posted by Efi69Cam

On the DFI wideband controller, if you have the new one that uses the NGK sensors (looks like a mini-me of the Gen 7) the only reason to use the speed sensor input is if you want a speed dependent control or for the data-logging functions.

Thanks for that info.I just have the single Bosch sensor to start with.

I have my racepak for data logging and would probably never use the data logging from the Accel, maybe when I get down the road I might change my mind but after it gets tuned I don't see me hooking a laptop to it unless I hit the drag strip and mess with a tune for that.

I am feeling like I am back at school with all of the programming I am learning.
It makes my head spin when I go too fast trying to learn it all. Setting stuff up gets confusing enough, especially when things are going wrong. I have learned a lot from things going wrong but man it gets old quick.

I was tuning a bit today and it was the first time I put the pedal to the floor quickly and it reved up to 6 k so fast I couldn't get my foot back up before it hit the rev limiter from what I could tell. It sounded good and strong. I am ready to get out and put the load on it ASAP.

[waynieZ]

I think the only one against you now is Mother Nature. I'm so sick of snow already! I know you feel the same.

[David Pozzi]

I'm planning on going to Motor State, but this year is going to be pretty busy, hope I can keep up!

[Jim Nilsen]

I kept looking at the harness from Accel and looking at the firewall and seeing where and what I want to go thru for wiring and finally decided to call O'Reily's and see if they had some weatherpac terminal removing tools available. Low and behold they told me they could have them for me tomorrow
morning for just $16 and it is the complete set needed to to all of the types of connectors. I just couldn't see fighting with them to do the job since I am messing with an important part of the system and want to save putting another hole in the firewall.

If it all works out I will be able to pull the old hego wire back in the cabin and at the same time pull the new eugo wire in with them making all of the connectors inside the car. It will be a bit harder to change out the O2 sensor later if needed but I will have the tool to do it with or I can push the uego wires back out where the hego wires went thru and put the connector back outside. Decisions decisions.

Why Accel didn't just make it so there was a plug for the wideband on the main harness to begin with is still a mystery to me, they had a plug for damn near everything else I would never use.

With the way the engine wants to run I think I am going to be glad I spent the money for the widebands ability to have better control. It seems to really like 12.5 to 13 a/f to get going really crisp according to the tables.

I keep saving my tunes everytime I mess with it so when I get out on the road I can pull over and put one in and see how it runs compared to the other and hopefully I can mix the best areas together and move along faster with it once we put it under load.

The one thing that gets me is that the idle will be spot on to the idle settings in idle program one minute and then without doing anything and the temp staying the same rpm will go down? I keep thinking it could be injector decay because of voltage but it happens above 13 volts which I thought injector decay didn't start until it got below 12.5 volts. I may need to change my alternator crank pulley to increase my voltage at 900 to 1000 rpm idle to the 14.1 I get at 1200 rpm. It is around 13 volts at 1000 rpm. anyone else ever have this happen? Or will it more than likely just be I need to get a better idle tune to get it to stabilize?

I can only hope it is easier to know with the wideband installed?

I have my old 9 pin serial port/XP Pro laptop up and working again and it likes the serial port and it also works with the usb. The wideband will have to go into one and the ecu in the other to tune it so I hope it can keep up.

[Jim Nilsen]

Originally Posted by David Pozzi

I'm planning on going to Motor State, but this year is going to be pretty busy, hope I can keep up!

If you are going to be driving Penny I think you will have no trouble keeping up

See you there

[GregWeld]

Jim --


It's not the A/F ratio that needs the tuning on the Accel Gen 7 --- you set the AF for what you want (or think) the motor needs (to get started tunning) and then you set the VE to get the ACTUAL A/F to match the desired A/F you set at that particular cell....

Now -- I can tell you that there are guys on here that REALLY know this stuff - so I'm just trying to throw you a bone here... "food for thought" really...

So lets say it's idling - at 750 rpms - and you want the AF to be 14.1 at idle...

You find the cell where it's idling - (or maybe it's hunting in 4 cells) - select those 4 cells - put in your 14.1 AF -- then go to the VE table and select those same 4 cells and start tunning those VE's until the actual and desired MATCH.

Now -- if the motor is too lean at 14.1 - just change the AF number to 13.5 or whatever - until the motor "Likes" the AF -- but the VE's won't change much regardless of the AF number selected. Of course you can find the AF the motor likes - get that going right - and then come back and 'tweak' the VE's - bringing them in so she'll idle (Watch your Map for best "vacuum" - no different than a carb!) and your Wide Band O2 has hardly any "work" to do... You really do not want the O2 to do much --- it's there for when it's needed -- but adding or subtracting 5% or LESS would be correct... At idle -- it shouldn't be adding or subtracting ANYTHING if the VE's are right.

Now -- I may be telling you stuff you already know... and if that's the case - then just skip over my posts...