I'm looking at possibly using the 8l90 in my build. I'm told that I may have to go with a 6l90 ...but I wanted to check with some tuners first. I already have an l9h I bought. Came with harness but no pcm or other electronics. Is it possible to make these two work or am I going to be forced into the 6l90? Could I maybe change some parts so a newer pcm from an 8l90 car/truck will work with the lh9?
The 6L80e/6L90e would be better because the E38 computer could control it.
Doubtful you could ever make the newer E92 computer that uses direct injection with a specific torque model style calibration to control the engine and transmission work with the older engine.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
That's a shame. Oh well. Maybe if anyone comes out with a stand alone at least its an easy swap.
How about the e78?Originally Posted by 5FDP
The E78 only came equipped with the 6L90e in the heavy duty trucks. (I'm not including the 4 cylinder engines that ran the same computer.)
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Ok... so Im using a l9h Engine From a truck. Or would that not matter? I dont know if the L9H was considered heavy duty and sold in the HD series trucks.
I guess I wasnt able to interpolate from your comment whether this would or wouldnt work.
I don't think there is an E78 operating system that can talk to a T87 TCM for your 8L90. In fact, the E78 itself may not be fast enough to communicate with a T87, GM actually went and revised some of the 4 cylinder DI ECMs to a faster CPU at the same time those engines started getting A8 and A9 transmissions.
E39 and E78 are essentially from the same generation and only ever drove A6 transmission equipped vehicles. When they switched to the A8 in the 2016 Cadillac ATS and Chevrolet Camaro, they also switched a newer, faster ECM, called the E80. The 2016 and 2017 Buick Regal with the same engine as the ATS and Camaro continued to use the E39, along with the A6 transmission.
There is a "next generation" MPFI ECM, called the E84, which might talk to the T87, but it seems highly unlikely there are any V8 OE calibrations for it.
So in short, unless someone builds an aftermarket 8L90 controller that can talk to your E38 (or E78), it's not likely this will ever be possible.
Thanks for your reply.. 2 points
1st, I agree that its probably not possible and my post regarding the E78 was intended for the 6L90.
2nd. This is really just a talking point... I dont know what the lt4 uses for ignition timing, sensor voltage, feedback, etc... but if torque mapping is what makes the shifts happen, then why not just put the new ECM and assorted sensors onto the old engine and remap it? Im not a very experienced tuner with GM' pcms, but i would suspect the shift mapping is really only telling the engine to back off the power very briefly, to let the shift happen. Then there is probably some timing things going on to "catch" the engine to help keep the rpms matched. (meaning using timing to help slow the engine down to prevent mesh issues)
It seems to me that collectively we could figure out how to make this work if someone can decipher the maps in the ECM. also, isnt the Canbus for the 8l90 on an open industry standard architecture this time around?
You cannot use the SIDI E92 ECM (LT4) with an MPFI engine (L9H).
Ok.. .but why cant you? as far as the ecm knows its just firing an injector. as far as the engine knows, its just getting fuel. the computer doesnt know the engine doesnt have an injector firing directly in the engine. if there is another sensor that causes an issue, could you not change it out?
Sorry I dont mean to sound combative, really just trying to figure out what the limits are.
im willing to concede there are certain parts of the engine tuning you may have to completly 0 out since is really just wont work without direct injection, but as far as controlling timing, and fuel the ecm should be able to do that on just about any engine with the right sensors.
Last edited by Motorsports-X; 10-09-2018 at 03:48 PM.
It's a direct injection engine computer that would be working a port fuel injection engine. They do not share the same parts and you can't make the computer control those injectors and all the other sensors.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Im talking outta my ass here since i dont know that much about how the actual fuel pulse is timed in the ECU. but if the injector resistances match, the ECM shouldnt care about the physical location of the injector....OTHER THAN... it will need to be re-timed so it injected during intake opening. (the assumption im making is thats an adjustable value in the tune.) or is there a completely different kind of injector driver profile that you need to take into consideration?
im coming from older sportbike ECMs which are no where near as complicated as the Modern GM stuff, but electricity is electricity right?
Actually GM DI injectors need 65 volts to open and 12 to control. I don't think that would sit well with a port injector.
now we're on to something.
I was just reading while on the subject of this thread and the new ZR1 has both port and DI. so that ECM (i beleive the e99) could work, assuming its eventually hacked.
Man GM is making this crap hard. If someone in the electronics/performance world would make some controllers for these new parts, they could make some serious money. But the fact you would have to basically standalone the entire drive train is really ridiculous and kind of goes against the last 40 years of automotive enthusiasm.
OK so the E80 can drive the T87?
Was the E80 also a made to drive a port fuel injection engine?
Was the E80 also a "torque model" ECU?
Are GM's TCM's #24284058 & #24284064 both T87's ?
Last edited by Jacb; 10-10-2018 at 12:04 AM.
E80 can drive the T87, but it is DI only. It's mutually exclusive, a GM ECU is either MPFI OR DI, not both. Yes, it is a torque model ECU. Think of it as a 4 cylinder engine version of the E92 in a sense.
The E99 is also DI only. There's a secondary fuel controller ECU called the S53 which drives the MPFI injectors, and it's a slave ECU to the E99.
Is there an injector driver module used to fire the DI or just the ecm?
The injector drivers are part of the ECM. That's why the DI ECMs got so much larger physically over the MPFI ECMs, to make room for those DI injector drivers and also provide sufficient cooling for them.
Hi tunerpro
This is all new to me so please be patient...... If I understand you correctly you are saying that if one was to get an E99 it could drive an S53 and a T87a at the same time?
The S53 would take care of the MPFI requirement and the E99 would run the T87a which in turn would run the 8L90E transmission.
Colud the HPTuner software handle such a setup .... is the S53 supported and what functions does it have?
Reply With Quote