Looking for some help on cam/headers tune LM7 5.3L (mostly spark)

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Originally Posted by 96SWB

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Next question: Since CALC.VET has consistently demonstrated that the MAF Cal is exactly correct (no change from stock cal) is CALC.VET really the best way to go (most accurate) tool to get my {B101} Main VE dead-nuts on, or would I be better off doing something like OL/MAFless/AutoVE on the dyno on Saturday?

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Yes, I agree, if MAF is good, then concentrate on OL/MAF-less/AutoVE (but lets use thepid CALC.WO2BEN from Calc.VET to do this, if possible)... so you will have time to play with HO spark table... try running the 2002 F-car HO table, but keep an eye on knock during load... I don't think you'll have any problem.

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Furthermore, I think the fueling is pretty darn close at least at every RPM/MAP i was able to measure on the streets. I didn't do much work above 4000/low KPa, because the truck was accelerating way too fast to collect frame counts up. Hopefully getting into those cells on the dyno will increase the peak #'s?

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When you get those numbers right, you will see instant response when doing a throttle WOT snap open.

96SWB, PM me. I'm local in Seattle and would be happy to help you. Im not able to come on Sat and help in realtime, but if you have some questions please feel free to reach out.

Joe will get you squared away, I havent done many LS1 PCMs simply as my personal and client vehicles have been P10 or E67 based.

Yah, with 220 cam, long tubes, and 3" catback you should see higher dyno numbers... but how does it accelerate on the street, can you fry tires...?

BTW: might need some transmission table tuning.

With the cam I take it you installed springs...?

Cool. Thanks again joecar, all excellent points you make, and all are well received / make good sense to me.

Excuse my ignorance, but I wanted to double check when you mention "2002 F-body H.O. table", do I understand that you are referring to "{B5913} Spark High-Octane Table" in a Stock F-body Cal? Or else, could you mean H.O., as in high output, like (WS6?) or (something???) :notsure:

ScarabEpic, awesome to hear, thank you for the offer!

Joecar, in term of your last post on how its running--To me, its disappointing, i know it's not there yet. I think it sometimes pulls out advance somewhere around the 2000rpm mark, which always decays out smoothly and doesn't "ratchet" the KR. It feels like it makes too much noise and takes too much pedal to get the thing to move, like its bogged. It runs a ton better than when I first started, though, and sometimes it feels pretty promising, but other times it's just kind of "blah" and flat up to maybe 2800-3000 then it feels like its waking up a bit if the KR is decayed out by then and hasn't returned.

I think I am going to seriously look at conservatively blending the LS1 spark tables with the my stock truck table so I can get a read on what that "feels" like.

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Originally Posted by joecar

With the cam I take it you installed springs...?

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Yeah Comp 918's i think or whatever they were supposed to be. It was a Texas speed deal with chomoly rods and springs. I am glad you concur that 295hp/282tq is soggy at best and total BS at worst. Because I did a lot of research and had heard of guys making up to 345hp with that cam on ~similar~ setups.

Edit: To be clear, my estimate or expectation has always been 325-330rwhp on a Dynojet, I know 345 is a stretch.

And yeah I am really confused about how that dyno chart was obtained. Notice it was only 45 minutes between runs, too. He had the car all day, but my friend was hiding out watching, unbeknown to the shop owner, and my friend said that he did a pull, waited like half an hour and did another pull, and that was all the time it had on the dyno total. The tuner/owner, said he was supposedly (supposed-to-be) working on his truck all day, because thats how long it "took". Anyways pretty clear that the guy was clueless or indifferent and ripped him off and didn't care. The truck runs worse on his tune than on the one it went there with, and the Calibration Difference Summary does all the talking. Still its like WTF did the HP come from though?

Thanks all; I'm lots of things, but ungrateful has never been one. I'm just trying to help a friend out here.

If it is a load bearing dyno, I would ask the shop owner how to apply load so you can work the tune sections at a time.

I was thinking about this last night and again this morning, Im frankly surprised your MAF correction was 1 across the board. IMHO, it shouldnt be unless you're running SD... Per Joe's description, Calc.VET calculates the VE and corrects MAF. How your MAF is the same as a stock tune when you used that data to calculate a correct VE...something's not adding up. It would explain the bog you get as well (experienced it on my own vehicles).

Maybe as a test, disable the MAF and run SD. With the VE table corrected, fueling should be spot on or very close. See if it bogs or anything like this, if it doesnt and pulls harder then the PCM might be trying to do something/blending of the MAF and VE tables.

Let me do a quick trans tune for you as well, should firm the shifts a bit and make them crisper without hurting trans life. In my experience, a tuned trans lasts longer than a stock one because with stock tune the clutches burn out due to slow shifts.

Calc.vet calculates the VE and corrects the maf. You had those two switched. I would verify you your selben is getting correction values.

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Originally Posted by ScarabEpic22

I was thinking about this last night and again this morning, Im frankly surprised your MAF correction was 1 across the board. IMHO, it shouldnt be unless you're running SD... Per Joe's description, Calc.VET calculates the MAF and corrects VE. How your MAF is the same as a stock tune when you used that data to calculate a correct VE...something's not adding up. It would explain the bog you get as well (experienced it on my own vehicles).

Maybe as a test, disable the MAF and run SD. With the VE table corrected, fueling should be spot on or very close. See if it bogs or anything like this, if it doesnt and pulls harder then the PCM might be trying to do something/blending of the MAF and VE tables.

Let me do a quick trans tune for you as well, should firm the shifts a bit and make them crisper without hurting trans life. In my experience, a tuned trans lasts longer than a stock one because with stock tune the clutches burn out due to slow shifts.

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ScarabEpic22,

Yeah I was always a bit confused at how values derived from instrument measurement could work out to be exactly 100.00% correct on the first time. I kind of poked around to see what might have been wrong, but I eventually dismissed it, figuring that, "Well, the MAF is stock, so who am I to argue with the GM calibration engineers?"

As an aside, last night I decided to completely start over with a clean sheet on Spark segment. Starting with {B5913} H. Oct. Spark, I actually printed out the tables from a factory 2002 LS1 calibrations, the factory 2002 Silverado LM7, and from a couple of other forum member's custom tunes who had camshafts. I did that because I'm a Mac guy, so I only have a little netbook to run EfiLive on, and its tough to look at multiple data sets on this 11 or-whatever-inch screen.

So, I spent a lot of time carefully making a "hybrid" of the different maps, probably giving the factory F-body tune the greatest weight, but also narrowing the band of "heat"
down a good little bit, and just generally doing my best to reconcile my common sense and grasp of the 220R cam vs the LS1 cam, and looking at other tables in the tune.

The result? Unbelievable! A short drive late last night blew me away. There are 2 little spots where the table is still too hot (around at 2600rpm/.44g/cyl), and I saw that I got into a little KR, but it always was brief and decayed out quick. So I have to touch that up here and there. But even with some KR the truck is pulling SO much harder at any RPM and just generally feels and sounds SO much healthier it was shocking. I also undid every single thing the dyno shop did to it, because none of them made any sense and the truck ran like absolutely turd on that guy's tune.

Additionally, I extrapolated/guesstimated some more air into {B101} Base VE above 4400.

I'm not exaggerating when I say it felt like I downloaded another 50hp into it with that one tune. I had it up in the mountains last night on the highway and did a 3rd gear roll starting at about 60, and it was up to 115 just about as fast as a pickup needs to do.

I have a couple more questions to ask in a bit I got to run 4 a minute..