92 zzz28

I guess the title says it all.

What are some good starting places for tuning the spark table?

Also:

I have been taking alot of datalogs recently, and I have notice with datamaster, that my O2 volts tend to stay high. They do go into the lower numbers, but then quickly rebound to higher numbers, above .700 volts. What does this mean, rich I think?


Another thing:

Recently, I have noticed that my acceleration in the low RPM range leaves something to be desired. Off the line kinda thing. It doesn't bog down or stumble, just doesn't have the twist I want. My car really takes off in the 3000+ range. Now I know a lot of that is due to my combination, Stealth Ram and 224/236 cam will explain that. WHat I am curious about though, is there a way to tune a PROM to help the low end some? Would adjusting the SA tables in the lower RPM to give more SA possibly help that?

BTW, I did do some searches, found lots of good info, as always, and even answered one of my questions I was going to ask here.

Thanks in advance
Ryan

3.8TransAM

Heres where i would start at:


First drive carefully and datalog the lower end as in 3000 rpm and under. Use the gathered info to note knock and where it occurs, and also to find where your blm is at(rich/lean) and then adjust accordingly to get it in the neighborhood of 128(+-8or so).

1 Pull some timing out of your MSA where u noted knock occured

2 Add/subtract fuel from VE table where u found u were over/under 128

3 If none of this made any sense to you by all means work your way thru the stickies at the top of this forum and read thru them, tons of basic issues and intro to tuning with great info contained therein.

4 after reading stickies and still have questions on issues , please feel free to ask questions


U have a lot more cam than stock and more cubes as well, but i still want to believe that cam will make u a lot richer under say 2.8-3k and especially near idle, and just off of idle

Running rich can really tend to make a car soggy, just as being lean and tip in can......pull some timing where you see knock and work on getting the VE tables near 128, then u can work on the other issues

LAter
Jeremy

92 zzz28

Cool thanks for the advice.

That all made perfect sense. I know I have a lot of work to do in the VE, my BLMs cruising are between 108 and 111. At idle I have gotten to be at 117-118.

As for the SA, I will start with that. I was looking at my stock table last night, it seems rather tame. Would I find any gain by trying to make it more aggressive? I know it is all dependent on what the engine wants.

Oh yeah, what do you think about getting 30-40 knock counts in a 15-20 min datalog drive? Does that seem high?

Thanks

TRAXION

IMHO, any F-Body modified with aluminum heads should automatically start with the ANHT spark tables. These are the stock Corvette spark tables and they are more aggressive than the F-body spark tables due to the fact the corvette got aluminum heads.

Tim

11sORbust

My experience is the opposite. I found that fbodies tend to detonate with the 6*+ timing of a vette bin. Seems to be caused by the heavy f-body and the engines was high compression 11:1-12:1. They did have al heads...

TRAXION

12:1 is a huge difference so of course there might be some pinging using ANHT tables. However, on all the 350ci motors I have seen that are running AFR heads .... they like the ANHT tables. This is with ~10:1 compression.

Tim

Ronny

iTrader: (1)

is that spark table on this forum or where could it be found? moates? i have been looking for spark tables to be compared with the one i am running. i have alum heads and 10/1 compression. my max spark is 33 deg.

TRAXION

Go to the bin library at diy-efi.org and then download the ANHT binary. There isn't that much difference in the WOT curve ... it's the part throttle curve that is hugely different.

Tim

92 zzz28

Trax,

Thanks for the info on the vette spark table. I will try that out soon.

Does anyone know what the stock comp. ratio of a ANHT vette was? Like 10:1 or so. I am curious because mine is lower than some...