Northstar 7165 OBD1 Bin creation and tuning

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Re: Northstar 7165 OBD1 Bin creation and tuning

Postby MAGP » Mon May 29, 2017 1:32 pm

As long as you have the correct settings for the type of ignition trigger, MAF or MAP, injectors, idle control, etc you can just about run any engine on any ecu. The larger the divergence from standard, i.e. what the ecu and program was originally intended for, the more difficult setting up a base tune and then doing a full tune will be. Believe it or not your 4.6 litre shouldn't be all that difficult to tune IF you have the same type of ignition, idle control and air measurement UNLESS there is a need to control VVT, DOD, or something like that that the ecu and program were never designed to control.

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Re: Northstar 7165 OBD1 Bin creation and tuning

Postby antus » Mon May 29, 2017 6:10 pm

Usually the closer to the stock tune you are the better. You will need to forego the knock sensor as on the '808 thats a tuned piezo microphone tuned to the frequency of the knock of the engine, and it'll be unlikely you'll be able to convert it. If you know what timings are being run stock you'll probably be ok to use these values. The other will be the crank sensor. The northstar has a wierd crank pattern and lots of people come through the forums looking for an alternate ignition options for the factory PCM (but with no luck). You'll need to swap to a reluctor in distributor and run a suitable ignition module. Beyond that, once timing is set up, dial up the correct injector rate and voltage dead times for your injectors, modify the crank stage 1 and 2 pulse widths by the difference in size between stock and your injectors to get the correct crank fuelling. Also modify the VE and Spark tables to match your application and you should be pretty in the ball park. There may be VSS PPK settings if the road speed logs incorrectly, or you might need to chance coolant or temp sensors or their calibration, but I suspect they'll be right. Someone else might have more info about that. I'd be inclined to try it and see.

Having said that, if the northstar ignition is the standard 4 wire delco interface you could use the stock ignition and change it only if/when it fails later and you have no other option.
Have you read the FAQ? For lots of information and links to significant threads see here: viewtopic.php?f=7&t=1396

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Re: Northstar 7165 OBD1 Bin creation and tuning

Postby delcowizzid » Mon May 29, 2017 10:07 pm

What sort of issues do you have with how it runs
If Its Got Gas Or Ass Count Me In.if it cant be fixed with a hammer you have an electrical problem

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Re: Northstar 7165 OBD1 Bin creation and tuning

Postby Daviero » Tue May 30, 2017 12:31 pm

delcowizzid wrote:What sort of issues do you have with how it runs


It actually runs well, but its not like a stock tune so it has some quirks.
First, Antus- I did do the math for the injectors and they are set up well. I forget how I connected to the Northstar crank sensors (there are two) but I did use them, and I use the stock coil pack and ignition modules. I also run a knock sensor, and interface that with an external knock filter. The knock sensor is definitely not tuned to the engine, (but its better than nothing I hope) - I used a similar displacement one but of and SBC - 305 I think. For VSS I use a GPS pulse generator, works great except in long tunnels.
The timing table is pretty well an imitation of the OBD2 table but in the 7165 format - that was easy.
The VE table is an interpolation of the stock OBD2 table and is tuned well enough - that was a chore.
So what does it do? These are some.....
Stopping quick at a light without allowing it to slow down easy will often cause the RPM to hunt up and down - a blast of throttle past the reset setpoint value will settle it down.
I have the A/C working on the car and at an idle the compressor clutch will engage and disengage pretty well seamlessly with the expected rise in RPM. But if you have the A/C on and the compressor is engaged when you come off a highway and stop - be prepared for an immediate stall, so i have to shut the A/C off before coming off the highway.
It runs very rich if I start it on a cold day - I know this is the cold temp VE modification chart, but how much richer is still to figure out.
The idle is not very steady - it wanders up and down 50 up 50 down.
Driving at low speeds in low gear it bucks when the idle searches.
Defco ends a bit abruptly when you slow down enough that it comes off - feels a bit like you let up on the brake a bit.
All these are not a problem on the highway or on the track. It makes good power and is fuel efficient if I keep my foot out of it.
Maybe I just need to download a bunch of tunes to see where a lot of these variables are for other engines? It would be so nice if I could use a close OBD1 stock tune to use a reference. Most of the OBD2 Bin I used for a source has different variables.
Thanks for looking, reading and offering your input - its much appreciated.
From what I gather, I am the only one running a Northstar in OBD1 on a 7165. Unfortunately.

Cheers,
Dave.
88 Pontiac Fiero GT

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Re: Northstar 7165 OBD1 Bin creation and tuning

Postby antus » Tue May 30, 2017 1:10 pm

Sorry I thought you were considering running a '165, not already on it. It sounds like you have a wideband connected. Can you post a log of something like a 10 minute drive, better if it has stalled or almost stalled on decel?
Have you read the FAQ? For lots of information and links to significant threads see here: viewtopic.php?f=7&t=1396

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Re: Northstar 7165 OBD1 Bin creation and tuning

Postby Daviero » Wed May 31, 2017 9:48 pm

antus wrote:Sorry I thought you were considering running a '165, not already on it. It sounds like you have a wideband connected. Can you post a log of something like a 10 minute drive, better if it has stalled or almost stalled on decel?

Yes I have the whole setup and I'm happy with how it works. I willpost a record - it'll take a few days, tied up at work and will need to play with recordings first. Been playing with the 7165 for over 4 years now bu not recorded much.
Thanks, Dave.
88 Pontiac Fiero GT

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Re: Northstar 7165 OBD1 Bin creation and tuning

Postby Dylan » Wed May 31, 2017 9:51 pm

How have your been adjusting the calibration for years without logging anything?

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Re: Northstar 7165 OBD1 Bin creation and tuning

Postby Daviero » Mon Jun 19, 2017 3:12 am

Dylan wrote:How have your been adjusting the calibration for years without logging anything?

Rightly or wrongly - yes. I have used the wideband on long steady hills in different gears and different loads to get the VE chart set. I usually do this with the laptop on the passenger seat. Other adjustments i have made live. and I have not done any logging and playback analysis. Form your comment I suspect the logging/playback method is the better way to do it?.

Cheers, Dave.
88 Pontiac Fiero GT

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