just got into tuning with my 91' camaro z28 .. 305 tpi (sd) .. 5 spd .. 3.08 posi

so far i have disabled egr, air, and put in my new injector flow rate ..

tried three different spark tables with different results ...

stock spark table - idle is sorta lopey , crappy open loop, allright in closed
vortec spark table - really smooth idle, no lope .. but not much power driving
lt1 spark table - really good cruising power in open loop (havent driven it in closed loop yet, just burned it this morning)

what do yall suggest i do ..

get the stock table and take out 3 degrees all over b/c of my vortec heads, or start with a different table and tune the ve table

im just getting started but i get the concept .. just gotta find a good datalogging program, dont really like tunerpro rt unless im just not doing something right, i like aldl b/c it gives you the graphs for blm's and stuff but it doesnt work for the 730' ecm ..

any ideas on a datalogging program

thanks

 

Take the best of the three tables and blend them into one.

Stock gives, not much better then LT1?
Vortec looks to be best in the idle (and off idle?) area
LT1 gives good cruising power

Need to remember that Vortec's came on trucks. Which are heavy and can run hot with a large load at times.

RBob.

 

ok got the lt1 into closed loop a second ago .. runs like absolute junk .. but runs really good in open loop (well better than stock)

im thinking of sticking with the stock .bin file and tune the ve's .. should i take out 2-3* at first like everyone says or just start datalogging ..

 

Did you pull the fuse to clear the ECM memory after each change?
The fueling corrections take time to relearn and you are probably struggling with that when it first goes into CL.
You could also try DataMaster (http://www.ttspowersystems.com/DataMaster.html)
Its only free for so many logging sessions before you have to buy it but has a graphical interface to the fueling that is easier to see whats happening.
Then find VEMaster for $8D on Moates site.
The datalog from DM imports into the program and gives you a "rough" correction to your fueling.
A few runs and the fueling will be runable (not perfect but runable)
Make copies of your bin before running it, it changes the file you select so its best to have a backup.
Set the correction to 126 rather than 128 seemed to give me better results until I was real close on the BLMs.
Adjust spark and repeat fuel corrections for the next ... years
(or until its "Good Enough")

Happy tuning.

 

tried a corvette 8d spark table / ve table a second ago .. ran allright .. but was REALLY rich ..

when it got into closed loop it was sitting / bouncing around 109-115 blm's ..

im going to stick with my stock tune, and start datalogging / messing with the ve tables ..

 

There's a lot more to tuning than making global changes for any specific engine combo (they're all different). For instance, just to find your optimum spark deg at idle you need to use a dial indicating timing light and Vac gauge, here's how; disconnect the EST, start eng, adjust dist to obtain the highest vacuum reading. While at the highest vacuum reading, turn dial on your timing light to see how much advance it took, this total timing is what you should plug into your SA table where your car idles. Of course, you need to datalog to find out what cells it idles in. Make sure you put everything back to original when done.

Tuning the remainder of your SA takes time... finding out what works best. The VE will change as you change your timing. Work both of those first after you've made required changes to the BIN. Your best bet is to start with your original bin or one of the S_AUJP versions. Tuning is a very iterative process and takes time. Be careful with changes to your SA and VE tables as you go, they need to be smooth. Use a smoothing tool frequently, TunerPro RT has one built in! Good luck!

 

If you're using the LTR manifold, then I wouldn't try to use SA (or even VE) tables from LT1's or other engines. The LT1 manifold is absolutely nothing like the TPI- and the calibration reflects that.

I'd start with the factory bin and tweak that until you get it where you want it.

 

i just found that smoothing tool last night .. works good to ..

as for the .bin .. i stayed with the stock bin, and have been doing a little tweaking ..

my cruise got awsome, but something happened to my low rpm's at high load, coming off a traffic light is bumpy and sometimes pops

just made a few small tweaks and hopefully it fixed it ..

 

pops are ususally a sign of being too lean on the AE or too much spark advance (or a combination of the two).

 

yea i knew that, and after taking a second look at the previous chip i burned .. i noticed i added timing to the whole table (2deg) .. and took out some fuel on the lower ve table according to a previous datalog ..

sectioned in part of the stock spark table around the idle area .. and added back a little bit of fuel .. so ill see how it goes in a second ..

dont have access to a laptop for a couple days (im borrowing my moms), so as soon as i get back to datalogging i should be able to smooth out some of the rough spots ..

other than that my cruise is pretty dang close, just gotta problem with the idle - 1350 rpm area .. but i might of just fixed it, ill let yall know in a couple hours ..

thanks for the help ..

 

I noticed you said you had vortec heads? I have vortec heads on my 350, but w/tbi and the EBL. I have about 10:1 comp, with a NOS cheater kit. FWIW, I have tried a few different "base" timing tables, to include the vortec, which was on the bottom of the group for worst WOT power. The
LT1 table posted here, I would have to find it for the link, has the best cuise, and off idle and "stomp" throttle response. So what I did was use the LT1 table, took uot some timing from 3200 rpm, 90-100kpa on up, and with 2d PE timing from idle to 2800 rpm, then 1d PE timing from 2800 on up. I am also running 28-29d total WOT timing right now, I have been playing with it from 28d to 34d and call tell a difference from the SOTP. I have about 20d timing at idle, I have a idle SA table, but you could do the same thing in the correct area, rpm/map, of you spark table.

I can tell you my particular vortec headed engine likes ALOT of timing down low, lower maps, and scaled off rather quickly as it apprroaches the higher map areas, 80 - 100 KPA. As far as other peoples engines, they are all different, sorry to say, I wish it was easier.

But that is just this engine, I've read all kinds of magazine articles about the running anywhere from 32 - 36 d total timing, but this seems to be too much on my fuel injected car, maybe a carbed car.

I guess what I am getting at, try all the "base" tables, log them. Take note on where at the engine is in the areas you like, i.e., cruise at say 2000 rpm and 45-55 kpa, then take another table and do the same. If that table runs good in the high rpm, take note. then idle and decel. Now take ALL the good parts of each table, plug them into a new bin, and smooth. Then try it out.

It's gonna take some time. If you make global changes, i.e., 2d from the whole timing table or ve table, your gonna end up making some areas better, some worst. You really can't do that and get good results. You have to log, log, log.

Good luck and keep us posted.

 

finaly someone with another vortec engine .. YAY .. lol

that probably will save me ALOT of frustration later on, so thanks alot ..

as for the tuning, ive been messing around with different tables, etc .. and put a stock chip back in and i got a "smoother" drive out of it .. as in idle, acceleration, etc ..

some of the other spark tables had better idle , cruise , wot , etc

someone did tell me to put in 34 for the WOT 3200 rpm and up .. did it, and it seemed to give me a good bit more power .. but i dont think i really need that much since i get almost the same power with the stock 28 degrees (or so)

done some datalogging .. and what is confusing me right now is everything under 2000rpm is 108 blm, except for 1100 rpm / 1200 rpm in the 40 - 60 kpa range ..

its strange b/c i spent all last night changing ve amounts, and then it drove like junk and still showed 108 for the blm's ..

what am i doing wrong .. im taking the datalogged blms divided by 128 ... then multiply it by the ve table value then enter in the new value ..

but something isnt working for me .. have no clue what it is ...

would anyone be willing to have a look at my datalog file (tunerpro rt) and see if they can see anything obviously wrong .. almost smashed the damn laptop last night b/c i wasted 3 hours and got nowhere ..

at idle right now its at 108 blm's and the INT is at 100 (plus or minus a couple)

thanks .