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CK5
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84 K20 "Ethel" Not an Sbc/NV4500/241C
- Thread starter sreidmx
- Start date
Semi restoration of a 1984 K20 pickup.
5.3 LS, nv4500, np241c.
How does it sound when cruising? I forget
That is quite accurate..
lol
lol
With the exhaust that loud I'm wondering how the trans noise could even be heard at all.
It’s louder.. plus it fills in the high frequency where the exhaust doesn’t!
Just so everyone knows.. speed density tuning is hard.. the maf was pretty easy to dial in.. gotta keep grinding away.. little bits at a time..
I took my coworker for a ride today.. I gotta say the 1-2 is a dang lot of fun.. it spins the tires for however long you want
<—- shit eatin grin
I took my coworker for a ride today.. I gotta say the 1-2 is a dang lot of fun.. it spins the tires for however long you want
<—- shit eatin grin
Any reason why you are doing speed density?
Turbos?
Wicked video Steve! 
All the guys here need to see this vid...when we ask for burn outs this is now what is expected!
All the guys here need to see this vid...when we ask for burn outs this is now what is expected!
Also curious, I know in the F@&$ world the MAF engines are capable of dealing with more changes than speed density
Just tuning it to compliment the Maf, mostly to take care of the transient stuff and to learn more about how this works.. if my maf had failed it wouldn’t have run, now once I get it dialed in, it’ll still run great regardless.. and yes boost at some point will happen..
I put new brakes on today, replaced the drag link ends and installed the proper molded hose to hook up my heater!! It’s now luxurious inside.. I don’t know what I am gonna do!
I put new brakes on today, replaced the drag link ends and installed the proper molded hose to hook up my heater!! It’s now luxurious inside.. I don’t know what I am gonna do!
Hey Steve, what year is the ls you put in?
454Sub
5/8 ton status
That's brilliant fyi. A stock LS swap I did wouldn't even fire up with the MAF unhooked. That's not great, and a failed one would run like complete
as well.
. This isn't the appropriate smiley thing but it is my favorite. And you have earned it. This is the tactic I am using on these next two I am doing. Saving for HPTuner/??? and figuring this exact thing out on all of them from now on. I prefer the MAF but the ability to run even remotely decent, let alone perfect regardless, is worth it's weight in gold.
2012
I totally agree, might as well build in as many failsafes as I can if possible??That's brilliant fyi. A stock LS swap I did wouldn't even fire up with the MAF unhooked. That's not great, and a failed one would run like complete
Variable cam timing is baddddd I played with my settings kind of to see how much of an impact this has on drivability.
So the stock can timing map has an egr retard region where the cam is overretarded to lower cylinder pressure and create some egr condition. Those degree values are as high as 24 in some spots.
I’ll do my best to explain this, the factory cam and phaser are setup so the cam is at 8.5BTDC but the ecm tables are not able to show a negative value, they start at 0-128 so you can only control the retard direction and home or 0 degrees on the map is 8.5 advanced. This took me a while to wrap my head around..
What I did was at 1000 rpm I started the retard at 1degree or 7.5BTDC and ended it at 12deg or 3.5ATDC at 6000rpm
The whole table is a ramp.. this is purely for experimentation.. I’ll be messing with this, the oem phaser can swing 52degrees. Not that I’ll be going there but it’s nice to know. I’ve limited the rpm of the engine to 6200 based on some research on the L99 Camaro motors using the same lifters and other parts, I felt it not conducive to be revving it higher than that. And for the record it is still pulling at 6k..
I’ll get some screen shots of the oem cam timing maps and what I’ve done so you can see how this works.
After driving it at lunch I can say with absolute certainty that this has changed the additude of the engine, now I haven’t quite figured out if it’s better or not, around town it feels like it’s making more torque, but the drive home is a long hill at low rpm (19-2400rpm) so we’ll see fun stuff!
So the stock can timing map has an egr retard region where the cam is overretarded to lower cylinder pressure and create some egr condition. Those degree values are as high as 24 in some spots.
I’ll do my best to explain this, the factory cam and phaser are setup so the cam is at 8.5BTDC but the ecm tables are not able to show a negative value, they start at 0-128 so you can only control the retard direction and home or 0 degrees on the map is 8.5 advanced. This took me a while to wrap my head around..
What I did was at 1000 rpm I started the retard at 1degree or 7.5BTDC and ended it at 12deg or 3.5ATDC at 6000rpm
The whole table is a ramp.. this is purely for experimentation.. I’ll be messing with this, the oem phaser can swing 52degrees. Not that I’ll be going there but it’s nice to know. I’ve limited the rpm of the engine to 6200 based on some research on the L99 Camaro motors using the same lifters and other parts, I felt it not conducive to be revving it higher than that. And for the record it is still pulling at 6k..
I’ll get some screen shots of the oem cam timing maps and what I’ve done so you can see how this works.
After driving it at lunch I can say with absolute certainty that this has changed the additude of the engine, now I haven’t quite figured out if it’s better or not, around town it feels like it’s making more torque, but the drive home is a long hill at low rpm (19-2400rpm) so we’ll see
fun stuff!
A lot of tuners are afraid to touch the cam phaser tables and just leave them stock. And as such a lot of aftermarket VVT cams come with optimized phaser tables. However cam phasing isn't a one size fits all. It should vary by the intended application. Rock on with your bad self
Thanks man, I do see a lot of what you are talking about and I also do not see much of anyone with few exceptions on strategy’s on this..A lot of tuners are afraid to touch the cam phaser tables and just leave them stock. And as such a lot of aftermarket VVT cams come with optimized phaser tables. However cam phasing isn't a one size fits all. It should vary by the intended application. Rock on with your bad self
so my report for this afternoons shenanigans are this.
Loosing the few degrees of advance below 3 k hurt the lower end enough to make me switch it to 0(8.5 BTDC) and I noticed a marked improvement right away, I also noticed some knock, so I backed off the timing 2 degrees in the resulting areas which fixed that. I can maintain speed much easier now.
I’m not sure why but with the cam retarded the vacuum went way up, I’ll have to do some reading on that but the problem for me is my cruise isn’t technically a light throttle almost no load deal, I have this dang hill to pull so it’s loaded pretty good in OD where it feels it’s able to pull it and it’s in 3rd when it can’t. Then I slow it down to 70 so I’m not spinnin 3k all the time. Flat ground areas it’s stupid how easy it’ll go 80 though..
I actually put a feature request in to hp tuners for the VSS mapping, problem is that the truck ecm is not actually setup to read vss voltages directly, it actually gets a buffered signal from the tcm and then calculates the VSS from Input shaft speed (auto) and the VSS signal the tcm adjusted and sent.. so this is the main cause for nobody being able to use an E38 ecm from a truck or any car that was auto originally and then swapped into something else. The only alternative I have found which I am not sure is a true and workable solution is to run a manual trans Os then enable VVT, I haven’t researched this but apparently some guy has a TA and is doing this.
We’ll see if support responds to my request or not.
As promised here is screenshots of the stock vvt table (there are 3 this is the low baro)
And here is the adjusted table, if you notice there is a huge amount of retard in the lower cyl airmass and rpm areas, then they basically start to roll the cam back at 3500, I dont fully understand the dynamics at play here but the seat of the pants dyno says in that specific zone its snappier. It also sounds smoother and more... organic?? if that makes any sense? It doesnt sound like it kind did before when the engine at cruise sounded a little unhappy lol..
Here is a log from today, this would be around 80 mph uphill and it was pretty warm.
And here is the adjusted table, if you notice there is a huge amount of retard in the lower cyl airmass and rpm areas, then they basically start to roll the cam back at 3500, I dont fully understand the dynamics at play here but the seat of the pants dyno says in that specific zone its snappier. It also sounds smoother and more... organic?? if that makes any sense? It doesnt sound like it kind did before when the engine at cruise sounded a little unhappy lol..
Here is a log from today, this would be around 80 mph uphill and it was pretty warm.
