Mickyinks

You only need credits for your car. So long as your tuner doesnt lock the tune you can change anything you like.
Im running 20-25 degrees timing at 1700rpm , very big cam tho

TimsLS1

Yes yours is a big cam, does it run smoothly at that rpm?

Mickyinks

Yes it does , but i need 3.73diff gear really, at 100kph in 6th im only at 1250rpm... Ill put 3.73 in once its back on the road.
The low rpm surge can be hard if new to tuning, ive only just started also. it took me around 70 odd tunes and logs, asking lots of questions ,reading lots on tuning, to get it where im happy with it. For me a lot of trial an error. Just make small changes and youll get it

TimsLS1

Yes that's true, I've often wondered just because a big cam will cruise at low rpm if it is tuned well like yours seems to be doesn't mean it's a good idea. Not that I would know, just wonder if the high overlap at low rpm is ok??

Mickyinks

The old cam had 36 degrees overlap, id occasionally get a buck here and there car park driving but once used to driving it very rarely.
I cruise easily at 1500rpm in 6th but thats 130kph, 100kph in fifth im at 1850rpm....
Theres lots of things tht can effect your surge...... fuel, spark , airflow, adaptive spark.... Start reading lol

ChopperDoc

Here is proof that big cams can be tamed. This cam is a Pat G cam, 244/252 631/631 @ 0.050... 114 + 4, 20 degrees overlap... Seat to seat (actual values) are 293/305, 93 degrees of overlap. The throttle body is a Fast 102, as well as the intake. I ported the IAC out to 3/8" and made this log shortly after. I was impressed at how well it idled down low. Actual tune setting is 800, ish... I used the scanner controls to drive it down and it idled smooth at 600 pretty easily.

Note the low spark numbers as I hit the throttle in the log. This does not buck, surge, or anything else. Spark is the biggest contributor to that. As said earlier, I'd try 25 in your case. Supposedly, somewhere around 33 degrees is the universal "MBT" for most engines at idle and low RPM. This means it's optimal spark, but that's not what you want if you have a cam surging or having trouble getting back to idle. Spark controls the torque output, so more (up to MBT) will increase it, and cause too much torque.

This is is a video of what we tuners are fumbling with on our fancy laptops during a run... This is the scanner, and there is massive amounts of data and potential for it. Almost anything you can think of can be logged so long as the PCM supports it, and if you are good at math too, you can make formulas to compare them to other channels and so forth. It's incredibly useful, and the bread and butter of tuning a car. Hope this helps your understanding a little better. And you fellas can feel special, this video is only available through that link because it's unlisted lol.

ChopperDoc

In that video I forgot to show the average. It is set to show the MAX spark that was read in any particular block. So here's a screenshot to show the average instead, so you can see what it was doing most of the time. Also keep in mind the spark idle corrections are why it's jumping around at idle. Otherwise known as adaptives.

TimsLS1

Thanks I really appreciate your posts, I'm still debating re buying the software or just take it to the tuner for its booking on Thursday for him to road tune it for the 3rd time. Or alternatively cancel the booking and put the money saved towards buying the HP tuners and with a bit of help and the videos I'd likely have good success in sorting out my tune. Also I asked my tuner and he doesn't want to lower my idle below 820 rpm which upsets me a little as I'm almost certain it would have a nice lumpy note to it at 700 rpm despite being a mild cam but not at 820 rpm.

G Atsma

Do you choose a cam for sound or performance? Your engine might not respond from 700 RPM as well as from 820. That is more important.

TimsLS1

Performance is more important, but having a nicer idle was a big factor in changing cams. It had a great idle (ie lumpy) before he tuned it, I guess he must have tuned the idle well because it's all gone, although I would think 700 isn't unreasonable.

LilJayV10

iTrader: (39)

My cam has 16 degrees of overlap, 233/242 111 +2. 11.5+ compression, 6 speed w/ 3.90's

Drives like stock. Right now it's tune 100% MAF and drives great.

I've started VE tuning, but honestly, it's been a PIA to tune. I actually tried to tune it in SDOL, which I have never done before, and the WB% error is waaayy less than using the SDCL.

It's been a while since I've messed with it because it drives fantastic with MAF only, but I don't want to leave it like that just because I'm not smart enough to run a hybrid SD/MAF tune.

TimsLS1

Well done!! Is yours a LS1?

Mickyinks

If you want it to sound lumpier, up/lower the spark in overspeed / underspeed adaptive spark

LilJayV10

iTrader: (39)

If that comment was directed at me, yes it is.

I will say that one of the reasons I think it has been pretty easy to tune is, my cam guy knows what the hell he is doing. But more importantly, right now, it has stock injectors, LS6 intake, stock TB and MAF.

I think when I put the Mamo FAST intake, 102 TB, 100 MAF I will have to spend more time on it, even running strictly MAF. Oh and bigger injectors because they are pretty much maxed out now, but as long as you use good injectors with good data, that's normally doesn't cause any drama.

I've tuned a few cars, I'm by faaaaaaaaaar from being an expert. There are a lot of people way smarter on here than me. No doubt about that.

NSFW

You're probably better off using one of these:
http://pcmhammer.com/
http://lsdroid.com/

Both are free software, both work with inexpensive, off-the-shelf hardware. This is the hardware to get, IMO: https://obdxpro.com/

You can save a few buck by buying an ObdLink ScanTool LX or SX, but reflashing takes longer with those.

The catch is that not all operating systems are supported. However there's a good chance that you can flash a supported operating system if you're willing to re-tune from scratch.

TimsLS1

Thanks I purchased it, I will be able to trial some software now and see if I can work my way through it, much appreciated.

TimsLS1

Road tuned again today with tuner for an hour then I drove it for another hour at 50 mph (80 kph) at 1700 rpm to check it, result is it improved. He set timing at around 25 from a previous 33, will still rattle the drivetrain back at forth at 6% throttle opening but that only occurs downhill in 5th at around 48 mph. At least now I can cruise to work at 50 mph economically on flat although still with some slight hesitation & fluctuations. Im still a little surprised it couldn't all be tuned out for such a small cam but now at least I can use it as my daily to work.

Will less timing lessen power at that rpm??

What do members think of my LS1 idle? Attached here.
Its small cam a Crow 217/228 110 LSA at 820 rpm

Mickyinks

Youll be surprised how quick you learn to drive around that buck/surge/rattle. Still good if you bought hp tuners, that way you can try different things yourself