Discussion
Getting close to booking IVA now and would be interested in LS7 owners/builders experience of putting an LS7 engined car through regarding emissions, I think we have noise nailed.
For those that have passed, what cats did you use and what was the setup. Does anyone know if there is any difference (leniency) between early and current LS7s, i.e is the test different/easier if the engine is related to a 2005 spec LS7 vs 2008/9/10/11?
Any tips very much appreciated.
Thanks
For those that have passed, what cats did you use and what was the setup. Does anyone know if there is any difference (leniency) between early and current LS7s, i.e is the test different/easier if the engine is related to a 2005 spec LS7 vs 2008/9/10/11?
Any tips very much appreciated.
Thanks
Thanks Steve.
Can anyone confirm if the standard GM ECU throws a wobbly in an Ultima due to the weight difference between an Ultima and what GM would consider a typical car this would go in to. I heard that earlier engines tripped to a limp home mode because the ECU was gettig confused, don't know if this is still the case.
Steve, Kyle, anyone else care to comment or advice?
Cheers again.
Can anyone confirm if the standard GM ECU throws a wobbly in an Ultima due to the weight difference between an Ultima and what GM would consider a typical car this would go in to. I heard that earlier engines tripped to a limp home mode because the ECU was gettig confused, don't know if this is still the case.
Steve, Kyle, anyone else care to comment or advice?
Cheers again.
Can of worms....
i presume you have an E67 ecm?
if so it could be close on emissions or miles off, we had one with a Escalade map on it so it was rich at low load just to get the thing moving! We have also had a LS1 map on a LS7 ecm and the norm seems to be either a Vette or a Camaro.Please remember the Vette and Camaro maps are looking for a nice cold air feed, which you cannot achieve in our midengine applications even with the GD airbox or the Ultima solution.
I would simply take the car to a friendly MOT station and check idle, fast idle, lambda and HC
you should pass, HC(200ppm) and Lambda without too much trouble, idle(.3) should be ok but fast idle(.2 at 2500rpm) tends to be the problem if your cats are ok you may be close but i bet you will be slightly high.
I have a very lean LS7 E67 mid engine Ecu (also a very lean LS3 ecu) that should sort the problems, ive seen differences from one ls3 to another even with the same ecm fitted. They may be crate engines but they are not all the same. Happy to help anyone with IVA emission issues.
i presume you have an E67 ecm?
if so it could be close on emissions or miles off, we had one with a Escalade map on it so it was rich at low load just to get the thing moving! We have also had a LS1 map on a LS7 ecm and the norm seems to be either a Vette or a Camaro.Please remember the Vette and Camaro maps are looking for a nice cold air feed, which you cannot achieve in our midengine applications even with the GD airbox or the Ultima solution.
I would simply take the car to a friendly MOT station and check idle, fast idle, lambda and HC
you should pass, HC(200ppm) and Lambda without too much trouble, idle(.3) should be ok but fast idle(.2 at 2500rpm) tends to be the problem if your cats are ok you may be close but i bet you will be slightly high.
I have a very lean LS7 E67 mid engine Ecu (also a very lean LS3 ecu) that should sort the problems, ive seen differences from one ls3 to another even with the same ecm fitted. They may be crate engines but they are not all the same. Happy to help anyone with IVA emission issues.
Edited by Gulf LS3 on Sunday 8th April 20:09
Gassing Station | Ultima | Top of Page | What's New | My Stuff


