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Is the 93 GTS LHE 2.3 with a 506 or 509 DME? If so tunerPro has a BIN definition and I 'm experienced in Tuner Pro and can program and review. You could send the chip to me OR get a minipro EEPROM reader, download the bin and email it or just down load TunerPro Free and DIY. There really isnt much to see.
When you say "ran better" Do you mean everywhere, all RPM or just at idle? I've found over the years larger injectors dont always act as you expect, there is injector lag or the time it takes to open / close the injector. This is referred to as Latency and many older ECM dont have an algorithm to account for it and the typical linear way of programming ECM's for injector sizing doesnt always work out IRL. Also some ECM's have a minimum injector pulse value that might be too long with larger injectors. In any case the list of parameter in TunerPro for the 928 are modest, (see last pix) nothing like the hundreds of parameter I'm used to seeing in the GM realm.
As you suspect, engine will run OK over a wide spectrum of rich AFR's. There almost no driveability differences with rich ratios from 10.5 to 14. That's a very wide error range when rich. Ususally engines will start to drown about 9:1. In my experience when an engine goes slightly lean you will get all sorts of driveabilty issue around 15:1 Some engine are better than others running lean, I've gotten a large mild cam'd high compression SBC to cruise at 17:1 with ZERO issues.
Last edited by icsamerica; 07-12-2022 at 02:42 PM.
The car ran better with the custom chips with 30# injectors - and I would love to know why.
I can read them in and compare to stock GTS. I would be surprised if there is any custom programming. The other AT chips I have seen are just timing and fuel dumps at 3/4 load. No new programming, including stock rev limit.
Originally Posted by icsamerica
Is the 93 GTS LHE 2.3 with a 506 or 509 DME? If so tunerPro has a BIN definition and I 'm experienced in Tuner Pro and can program and review.
GTS bins are (annoyingly) offset versus S4 and GT because of additional diagnostic code. (I made my own much more detailed Tunerpro XDFs for EZK and LH.)
When you say "ran better" Do you mean everywhere, all RPM or just at idle? I've found over the years larger injectors don't always act as you expect, there is injector lag or the time it takes to open / close the injector. This is referred to as Latency and many older ECM don't have an algorithm to account for it and the typical linear way of programming ECM's for injector sizing doesn't always work out IRL. Also some ECM's have a minimum injector pulse value that might be too long with larger injectors. In any case the list of parameter in TunerPro for the 928 are modest, (see last pix) nothing like the hundreds of parameter I'm used to seeing in the GM realm.
As you suspect, engine will run OK over a wide spectrum of rich AFR's. There almost no drivability differences with rich ratios from 10.5 to 14. That's a very wide error range when rich. Usually engines will start to drown about 9:1. In my experience when an engine goes slightly lean you will get all sorts of drivability issue around 15:1 Some engine are better than others running lean, I've gotten a large mild cam'd high compression SBC to cruise at 17:1 with ZERO issues.
Better, in that it was drivable and the idle was lumpy but that could be the cams. No surging, no bucking. Now, the car has two modes uneven power at constant throttle between 2-3k RPM and warp speed. Demented.
It's been a long time so my memory might be the best. But, I wasn't reluctant to drive it.
That was before the fuel pump got so clogged with rust that it stopped running. :-)
That was AutoAuthority chips, stock manifold and 30# injectors. Fuel pressure dampers and regulators were as the car was delivered.
Once I had the computers back with an S4 bins and ST2 set to 30# injectors the whole thing hit the fan. Again, stock manifold refreshed plumbing and 30# injectors. Fuel pressure dampers and regulators were as the car was delivered.
KB
Last edited by Kevin in Atlanta; 07-12-2022 at 03:44 PM.
I can read them in and compare to stock GTS. I would be surprised if there is any custom programming. The other AT chips I have seen are just timing and fuel dumps at 3/4 load. No new programming, including stock rev limit.
GTS bins are (annoyingly) offset versus S4 and GT because of additional diagnostic code. (I made my own much more detailed Tunerpro XDFs for EZK and LH.)