224/228 581/588 112 tuning

[TLKSCHP]

Anyone running this cam or done any dyno time with one?
Hopefully I will be starting it up today but I really don't know allot about this cam. Can anyone tell me what RPM is best to shift at for the 1/4. I will be hitting the track tonight if it's running to start some tuning. Or anyone with a file to look through.

here is my current mods

98 A4 C5
Stock heads except Comp 918's
LS6 intake, Vara ram, Lt headers, Dr gas off road X, B&B Route 66, Pro torque 2400, built 4l60E, 3.73's, M/T Drags, and now a 224/228 581/588 112 Comp XER cam. Before I went 12.37

Thanks John

[SSpdDmon]

Typically, shift points are determined by where you make your power. However, given you have a '98 I wouldn't suggest shifting much after 6500RPM. The rod bolts aren't really as strong as the newer '01+ LS1's. As for tuning, it should be fairly similar to tuning any cam'd car. Get the AFR dialed in and then work on spark. It will like a little more spark over stock in the low airflow and idle ranges (less than .32 grams/cyl) and may take a couple more degrees of spark above 2400 at part throttle (less than .60 grams/cyl). WOT spark tuning usually needs some kind of measurement (track/dyno). Just make sure that if you're dialing it in on a dynojet that you remember the load on the street will be a little harder on the motor (may like a little less spark and a little more fuel for the street).

[joecar]

Additionally, because the 4L60E's ratios are spread out, you want to shift at the highest RPM you can get away with (see SSpdDmon's comments); this will allow your RPM to be higher at the start of the next gear (and high stall converter extends the RPM further)...
this does 2 things:
1. puts you higher in the torque band (see 2.);
2. keeps the RPM up (power is propotional to rpm and torque).

[Bruce Melton]

Careful, as SSD says those rod bolts are not good. Ask me how I know and I will tell you about my NEW engine.
If you can, change the bolts for good ones and save the heartbreak.

[joecar]

Yes, caution!

[TLKSCHP]

Well I was told this should start and idle with this cam, guess not. After warming up it doesn't want to re start or idle at all unless you give it some peddle and hold it over 1K. Looks like I have some tuning ahead of me. I still have a 408 camero waiting on tuning Might just have to pay someone.



Thanks for the word of caution on the Rod Bolts, unfortunately I don't plan on removing this engine again unless it blows so if thats it's fate so be it. No one ever told me fairly stock car would explode the flex plate blowing holes into the bell housing and firewall but it happened. The way I drive I give it 3 months till I shell the rear and tranny or the rod bolts. This thing is the most fragile car I have ever owned.

[SSpdDmon]

To get the car to idle, add 3~4 grams/sec to the desired airflow table. You'll also need to increase idle rpms some (at least 800). The base spark tables need to be adjusted as well. You can use the bi-directional controls to find what it likes. I'd guess 28* for base spark in gear at idle and 22* for base spark in park/neutral at idle to start.

One thing I noticed that was useful...look at the table in the tuning software. Around the edges are the PIDs for the tables. If you're logging those PIDs in the scanner, you can open the tuning software at the same time and see which cells are being looked at by the PCM. For example, while logging/recording the GM.DYNCYLAIR_DMA, SAE.RPM, and SAE.SPARKADV, open the tuning software to one of the base spark tables and you'll see a light blue indicator in one of the cells showing the current cell being sampled. It will move around as you drive. The rest is just knowing when each table is being used by the PCM.

[TLKSCHP]

Thanks,
If the wife lets me I plan on spending my day trying to get this so I might be checking in and out. We have to many modded cars around here with out tunes, it's sad. 05 GTO with a 402,turbo 400, a 2000 408 maro, 436 C5, and the list goes on, so sad

[mattsls1]

Very sad LOL

[TLKSCHP]

Ok here is where I'm at since i haven't had allot of time to play with the tunning yet. I got the car idling fair and can go from drive to park with barely any change but it's running way lean I guess. If you rev it up and let it drop the idle will start to bounce but if you ease on the gas and let it find itself it's fine. The wide band is showing 15-16 and the fuel trims show -4.8 which I thought meant rich but the exhaust fumes will just kill you and burn your eyes in about 3 minutes in a 40x60 shop. what do I need to do: fatten it up some in the low VE's? I tried using the BIDI controls and adding more fuel but I think I got in to big a hurry now that I think about it and made to fast of adjustments, cause the more fuel i added the more it stumbled, probably should add slow? Also not sure the IAC is reading but it's active in my pids and gage, it just stayed at 160 no matter what I did with the car. Just thought I would make an update post The wife isn't allowing me much time and i want to race come Wednesday before the weather here gets much worse