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mflora
April 22nd, 2020, 03:22 PM
Hello all, stalking on the site for some time now, but mostly in the diesel section.

I have a 5.3 with a big cam and LS6 intake, DBW throttle body and injectors(28.8).
I am trying to get it started. I had a stock tune in it and pings like crazy. I did manage at one point to get it running and driving with a 15-20 min log, but would not idle for crap in P/N, in gear was decent. But now it will not start again.
Did a lot of searching on but so far nothing has helped out and I seem to be going backwards now.
Anyone have some solid suggestions and explain them in simple terms as I am still trying to figure out what I am doing.

tune and log are attached. Any help would be greatly appreciated.

Cam specs are:
242/254 duration @ .050''
113 lobe separation, 109 intake centerline (113+4)
.621''/.612'' lift with 1.7 rockers

Wideband: AEM 30-0300 and I do have it working via serial comms.

statesman
April 23rd, 2020, 03:51 AM
That cam's too big for a 5.3 engine.

ScarabEpic22
April 23rd, 2020, 05:22 AM
Hate to say it, but agree with statesman on this. That would be a large cam on a 6.0 or 6.2. I found a similar cam on Cammotion's site, it's for rectangle port heads (which only work on 6.0L and larger bore size), recommended for 402-418ci, and a single plane intake (not a factory intake manifold).

Search for the Calc.VET or Calc.MAFT processes on here, that will let you get the VE and MAF tables squared away. As for idle, search for the idle tutorial (also on here) and start being aggressive with changes. That cam is going to be tough to have it idle well in your setup.

mflora
April 23rd, 2020, 08:15 AM
Changed out the cam in the car. It now has a Summit 8707 specs are:
226/238 @050 113+3 LSA, .600/.600 Lift.
So far I have it running pretty good and have completed Calc.VET: correcting MAF and calculating VE (in single log) twice now and hopefully correctly, as P0102 is now gone.
I would like some pointers on trying to get it to run better as it is running rich, still have P0101 code and the car will not idle when hot.
Have not done RAFIG/RAFPN yet.
Also an somebody tell me how to attach more files to this thread? I have tried several times now with no luck.

mflora
May 18th, 2020, 09:48 AM
Changed out the cam in the car. It now has a Summit 8707 specs are:
226/238 @050 113+3 LSA, .600/.600 Lift.
So far I have it running pretty good and have completed Calc.VET: correcting MAF and calculating VE (in single log) twice now and hopefully correctly, as P0102 is now gone.
I would like some pointers on trying to get it to run better as it is running rich and still learning, still have P0101 code and the car will not idle when hot. Have not done RAFIG/RAFPN yet.
Attached log and current tune. Log is only about 20 min.2330523306

mflora
May 18th, 2020, 09:52 AM
Changed out the cam in the car. It now has a Summit 8707 specs are:
226/238 @050 113+3 LSA, .600/.600 Lift.
So far I have it running pretty good and have completed Calc.VET: correcting MAF and calculating VE (in single log) twice now and hopefully correctly, as P0102 is now gone.
I would like some pointers on trying to get it to run better as it is running rich, still have P0101 code and the car will not idle when hot. Have not done RAFIG/RAFPN yet.
Attached log and current tune. Log is only about 20 min.23307 23308

mflora
May 19th, 2020, 08:10 AM
Have a new cam in the car now (Summit 8707 Pro LS Cam). Have completed a couple of Calc.Vet sessions but sill having some idle problems. P0101 is still set and P0102 is gone. Have not yet completed RAFIG/PN for the idle yet. Trying to attach current tune and log for some advice, but I have tried twice now with no luck. Anyone have some pointers for attaching files when replying to a thread?

ScarabEpic22
May 19th, 2020, 08:17 AM
It's a bit convoluted: Click Go Advanced -> Manage Attachments -> Add Files -> Choose Files. Select the files and click Open. Then click Upload. Make sure they're selected, then click Done. They'll be attached to your reply when you post.

Calc.VET won't help much with idle, you'll need to work on the idle separately as well. Calc.VET will get the airflow correct, but you'll need to work with IAC, throttle follower/cracker, and spark timing to dial the idle quality in.

mflora
May 19th, 2020, 08:47 AM
Current tune and log. If someone could review and give me a few tips that would be awesome!
Thanks for the info ScarabEpic22!

mflora
May 19th, 2020, 08:49 AM
Just tried posting, said I have to wait for a moderator to approve.

joecar
May 27th, 2020, 08:57 PM
Just tried posting, said I have to wait for a moderator to approve.
Done.

mflora
May 28th, 2020, 02:41 PM
Thanks, Joe. Will post up my tune once I get a better log.

mflora
June 3rd, 2020, 03:05 PM
Was finally able to get a good 40 min log in. Mostly having some issues at lower engine speeds in gear. Also wants to idle around 1100 rpm but think that might be due to settings in B4307. When trying in accelerate in drive the car goes super lean for a second or two and surges. But if I drop down in to second and give it gas it takes off like it should, any ideas. Will also take some advice and making my current tune better. I am following the Calc.VET: correcting MAF and calculating VE (in single log) process, only the basics so far. See attached log and tune.2332423325

Boost
August 18th, 2021, 03:10 AM
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