N/A EFI Cars ;)
Have you noticed the GM Stock Tune doesn't even go that rich???
Printable View
N/A EFI Cars ;)
Have you noticed the GM Stock Tune doesn't even go that rich???
I think everyone "forgets" that the LNF is direct injected. Totally different technology than port injected. The injection of the fuel directly into the combustion chamber via a high pressure fuel pump which atomizes the fuel allows you to run the mixture much leaner without raising the combustion chamber temperatures. Injecting too much fuel can cause fuel wash of the cylinder walls which can damage the rings. In a DI car you shouldn't need to go richer than ~.85, except for COT protection, in most situations.
I get it back to play with shortly, and with an EGT this time, so we shall see.
Hopefully it's a real EGT, the one in the ECU is calculated. Too rich on mine = knock. .88 is golden on 93 pump gas for most.
Wow... .80 lambda. The car hates you. Tuning for one of the biggest LNF companies in the market, and compiling all of our results, and all of the results from the most respected guys here (IAB, BYT, & TERM, mainly), the resulting torque from leaning it out is substantial. Yours had to have been a fluke. I typically pick up around 10 ft lbs for each .1 lambda I lean out. My base map starts at .84 lambda, and I usually run customer cars at .86. This is extremely conservative in these cars.
Play with it some more, and I am willing to bet you get better results. Running this lean on a DI motor is no issue. Running rich has been proven time and time again to cause knock, and I have noticed I can run quite a bit more timing on top, if i run it leaner.
Heck, we run one of our big turbo cars at 13.0 afr, without a stitch of knock. Ran a meth injected car at 14.0afr, with no knock. These motors love lean. See, what you notice in port injected cars, as you lean them out, you see more knock. This is what kills the motors. Not the case here. Sure, we might be playing with heat a bit, but you have to think, something will heat up to the point that it would cause preignition... so it would knock.
Just my point of view.
It's a stand alone EGT, independent of PCM totally. I have already talked to the owner about a nice progressive methanol kit from Alkycontrol and he is in favor. The car made good gains with timing and the move from 14.5deg-up showed the first small return on this setup, so I went back to 14.5. I couldn't know if it was a fluke on the first car, but I ran from stock to further down in steps and it just didn't have impact.
At any rate I hope to see more of these in the future (almost ALL v8 work), and I appreciate the advice given here.
Yeah, these are ALOT different than the V8's. Its very weird to compare them. Basically, for meth, we run about a 14.0afr, and still relatively conservative timing (for meth, at least) around 18* or so. the most power we pick up is actually from running the car so much leaner, and the fact the air charge is so much cooler. I would be interested to see the EGT gauge log though. I have never used one on the LNF, since we really haven't had any issues with heat on anything we have tuned.
Remember, false knock is very prevalent on the Ecotecs too. So you may be seeing false knock.
It had some real knock in some places but it was less than expected. I wasn't comparing them to V8s, I was saying that is what I get on the daily. The EGT is nice; alleviates doubt.
I know you weren't comparing, I was. The V8's have a million tables to confuse, lol. Must be nice, haha.
It should make a difference. My car on 0.84 lambda is slower on my acceleration times vs 0.88 lambda. The difference between 0.88 lambda and 0.78 lambda is even more significant on my acceleration times (about a full second or longer on a 60-100 pull). No matter what you do richer with more timing will end up being slower than leaner with less timing on these cars. These cars love 0.88 lambda
Good news for the LNF guys! I have some insider info that the new LS series engines will have a potential upgrades for the LNF :D
Keeping my eyes open for some opportunities to come out with some WERKS solutions for ya guys :D
4 additional cylinders??? :D
I think I smell bigger injectors.
No and yes, and some more. I am supposed to keep it on the DL, so thats all you get right now. Hopefully I can get some more information on it, present it to the boss man, and POTENTIALLY grab up some prototype parts to start some testing :D
I'd take an LS9 in a Kappa plz.
I remember a long while back GM showed off some GDI LSx motor, but they went dark after that. Must be coming back online. I ASSume this will be called Gen V.
We can do that :D
Well, we SHOULD be able to do that, assuming someone comes up with the money, haha.
We are doing alot of conversions right now for a company, which is helping the R&D of the V8 swap. Things such as the new 4L90E from the new CTS-V with the flappy paddles being fully integrated just like OEM, plus a few other options. But, this isn't the place for that :D
I know this is off topic, but how does the 6spd auto from the mailibu handle power? it would be nice to have a 6spd lol.
Does it have to be Auto? Can you get me the trans code for it? Basically, to break down the trans codes, the # in the code is the Newton Meters of tq it can handle. IDK the conversion off the top of my head, but say a 4T45 is in the car, it can handle 450 NM of tq.
450 N/m = 331 ft/lbs.
idk the trans code, I know its in this malibu rental I have lol, I prefer a stick but this auto has better gear ratios and autos are good for straight line. also it has the button shift on the shifter which I'm sure could be converted to paddle shift that I've seen on other chevy 4cyls(my hhr actually has the holes for the mount but idk bout cobalts)
I didn't realize that's how the trans worked, does the 92 4t65e handle 650nm? I didn't think it did... I thought it was 4(spd)t(transaxle)6(cyl)5(dunno)e(electronic)
Not sure how you are going to control it all, but I think I remember you saying a manual controller. Which, won't be very street friendly, but who cares (right?).
But yes, I think thats how all GM Autos work, the like the F35 should hold 350nm of tq. The first is the # of gears, the T for transverse and ## for NM.
You definitely won't be able to use the ECM, but, since you have an HHR maybe use the different body harness and ECM.
The '65' is just a series number, it has no real meaning, and definitely does not reflect the torque rating.
For the record, a 4T65e is rated at 380Nm at the engine.
I should also point out that the correlation between torque rating and RPO on the manuals is purely coincidental as well.
The LSJ F35 might be rated at '350Nm', however note that said number is the gearbox rating. The engine rating is 271Nm.
Further more, the LNF F35 is rated by GM at 353Nm (ask GM wtf on that one). As well, the G6 F40 is rated at 333Nm.
The brothers LNF seems quite happy at .86, and has no knock at all.
I have been fiddling with my tune and the car flies, but I am a little concerned about the amount of boost I am seeing.
I started with a GM Stage tune and 3 bar MAP sensors. I have my Max Airload Torque Table set to the numbers in the OP, and my DAL table peaks at 324.99, but I am seeing boost of up to 28PSI. The DIC readout stops at 25 and sits there until I get to 5800 or so rpm. I have timing set to 13 up top and occasionally I see little knock (if I forget to disable traction control) when TC intervenes..
Should I reduce the DAL table?
Yea, with a GMS1 base file the WGDC% is higher if you watch the Boost Desired %. Try running 255 down the right 2 columns of your DAL chart and adjust from there to suit :)
Comparing WGDC Boost Desired % to a stock non-GMS1 file, there is very little difference. No difference in the 100 column. I have a SKY Redline...
I have no problem making and holding whatever wg% commanded.. I posted the table Im using.
Honestly I think your table makes more sence BYT, thats how I set mine up give or take a few numbers.
Thanks, the car does not need more then 70% WGDC below 3k, so limit it to that. Makes it drive better too IMO, no crazy part throttle spikes.
Ya, I played with this table on saturday and ran faster in the 60-100 then I did with everything on the car lol. Im putting everything back on this weekend so Im hoping ill finally break under 4.8....My dreaded number
I'm fairly new to the whole tuning this but as I'm data logging, I notice I'm getting KR when I let off the gas. I have the purge solenoid disconnected. Any thoughts? Is this real knock or is the car just spitting that out when the fuel cuts off?
Prolly not real. I would check the BPV diaphram for tears.
I finally got the chance to take it apart. Looks like new, didn't see any tears or cracks or anything of the sort. The mount of KR I'm seeing is <2.5 but it's in the mid range so I'm trying to pinpoint the problem and tune it back. Basically what I've done so far is changed the power enrich lambda to 0.87 at WOT like the guide has, changed the torque management values and slightly increased the airload tables but not to the extent of the guide. I haven't played with the timing yet but I would think advancing the timing would only make things worse?
Getting the fuel trims spot on helps the midrange/midload KR the most. If it's that light, it's no big deal on the LNF.
Get the fuel trims on point and then reduce the mid load timing slightly. Sounds like its not bad.