Dyno Tune Question

[PonyKiller87]

I want to get my truck in on the dyno and get it tuned to get it running a little smoother and get some more milage / power out of it.

My question is I have my own copy of HP Tuners and started working on the tune already. Biggest thing so far is changed the injector tables for LS6 injectors. Other than that its just stuff like turning off rear O2. What I would like is to get it tuned but also to learn how to do it in the process so as I continue to mod it down the road I can adjust the tune on my own.

I guess I was thinking being that I would be providing the tuning software put the cost of that twards teaching me how to do it?

[WickedSix]

think the bitch will survive the dyno?

[PonyKiller87]

think the bitch will survive the dyno?

I think it probably needs a little work on the tune first to make sure its ok. After that theres only one way to find out.


Oh yeah, for a Wide band O2 where would be the best place to put in the sensor? The truck has no cats, 3" from the exhaust manifolds, into an x-pipe, then 3" back. Should I just pick one side after the x-pipe or should I mount it in the middle of the x-pipe?

[BAD LS1]

Kevin,

That is no issue to have it dialed in using your own laptop/cable. WBD will just charge by the hour for the use of the dyno which $85 for each hour. As to the second part of your question about learning how to do it... Education is not free. I'd end up being the guy who would be showing you what/how to do with the tuning end of it and id probably charge what i normally would for a complete tune for the training process.

Putting the wideband in either downleg coming off the manifolds will work fine for location. Essentially either side of the engine will produce close to the same AFR results.

[Dr.Buick]

Kevin,

That is no issue to have it dialed in using your own laptop/cable. WBD will just charge by the hour for the use of the dyno which $85 for each hour. As to the second part of your question about learning how to do it... Education is not free. I'd end up being the guy who would be showing you what/how to do with the tuning end of it and id probably charge what i normally would for a complete tune for the training process.

Putting the wideband in either downleg coming off the manifolds will work fine for location. Essentially either side of the engine will produce close to the same AFR results.

Tom is the man. he can teach you a lot.just pay attention

[WickedSix]

I think it probably needs a little work on the tune first to make sure its ok. After that theres only one way to find out.

its going to be rather loud there that day

[BAD LS1]

Lol throw some kitty litter in the box and some dust pans!

[GTO RLY?]

I got my own copy of HP tuners a while back. I got a "Definition Failed to Load" when I tried to read the tune on my Grand Am... and I haven't gotten the GTO out of storage yet.

What I'm doing for now is just logging, logging, and more logging of the stock tune, and reviewing the data under various conditions, getting a feel of what looks normal and how the motor reacts to your input and the like. Looks like the first thing I'm going to tackle on my GA once I can is the spark tables, I get very high spark advance spikes (as much as 35* advance) in the low 1-2k RPM range at 10-20% TPS. I have a basic understanding of how spark and fuel affect performance, but all my experience has been with carbs, distributors, and points.

[BAD LS1]

I got my own copy of HP tuners a while back. I got a "Definition Failed to Load" when I tried to read the tune on my Grand Am... and I haven't gotten the GTO out of storage yet.

What I'm doing for now is just logging, logging, and more logging of the stock tune, and reviewing the data under various conditions, getting a feel of what looks normal and how the motor reacts to your input and the like. Looks like the first thing I'm going to tackle on my GA once I can is the spark tables, I get very high spark advance spikes (as much as 35* advance) in the low 1-2k RPM range at 10-20% TPS. I have a basic understanding of how spark and fuel affect performance, but all my experience has been with carbs, distributors, and points.

Then you would understand why there is that much spark advance under low load situations like that Think of what a vacuum advance does for a distributor...

[GTO RLY?]

It doesn't seem necessary though, unless it's to prevent backfiring. I've noticed there is somewhat of a pattern between MAPS and spark advance, but in a decel condition, anything beyond initial advance seems unnecessary, which is where I tend to get the most radical spikes. I know I'm a total n00b, but it just didn't seem right. I'm not saying the factory tune is bad, but my Ecotec seems like it knocks between 1500-2000k or so, which is the area I've really kept my eye on. A 5th gear pull @WOT from 40 shows maybe 12* advance but I still hear it.

I still have lots of reading to do too. :P

[BAD LS1]

It doesn't seem necessary though, unless it's to prevent backfiring. I've noticed there is somewhat of a pattern between MAPS and spark advance, but in a decel condition, anything beyond initial advance seems unnecessary, which is where I tend to get the most radical spikes. I know I'm a total n00b, but it just didn't seem right. I'm not saying the factory tune is bad, but my Ecotec seems like it knocks between 1500-2000k or so, which is the area I've really kept my eye on. A 5th gear pull @WOT from 40 shows maybe 12* advance but I still hear it.

I still have lots of reading to do too. :P

Yeah, your gonna have to understand engine theory in detail beyond suck,squeeze,bang,blow to know why that much advance is used under light load conditions. You should see some 5.3 k-trucks, they run 50 degrees advance in light load. Unfortunantly the scanner doesnt support the ecotec KR pid for 02-04 cars with the L61 so you cant tell. My Saturn makes that same clatter noise in that range and i see no drop to the overall advance. 89 or 93 octane doesnt fix it either, its just a mechanical or harmonic noise from somewhere. Im able to run 23 degrees PEAK at WOT on my ecotec on 87 yet. Naturally a 5th gear pull from 40 is gonna be the most apt to produce knock as you are loading the engine so hard, try the 1:1 gear, 4th.

But in all honesty, if you dont understand what you are affecting by making adjustments or why they are the way they are from the factory, you shouldnt be tuning.

Here is the what the stock HO MBT timing table looks like from an older vintage L61 to get a feel for the timing ranges. Note you are running in the 50-60 Kpa range at hiway speeds at 2400 +, dont forget about adders and multipliers that affect the final numbers delivered to the spark plugs too that arent seen here. These numbers dont reflect WOT timing in the 90-100 KPA range either as there is a specific timing map for PE.

[GTO RLY?]

Well I haven't changed anything yet since I haven't been able to open anything with the VCM editor... and I don't plan on changing anything with the GTO much beyond the CAGS and fan temps yet until I get worthy mods that necessitate it.

I didn't get serious and install my wideband, that's waiting to go on the GTO when I bring it out of storage. I know that's the biggie that I'm missing so far.

[Z28Envy]

When you melt it down will you promise to come back and tell us about it!

[GTO RLY?]

Cuz that's what's gonna happen...

[GTO RLY?]

I did pick up this book published in the 70's called "Performance Tuning in Theory and Practice" that explained the timing spikes I was seeing under the conditions. It's aged, but it has a lot of information I never considered before, like combustion rate/speed. Good reading.

[BAD LS1]

It may actually benefit from MORE timing in part throttle.

[GTO RLY?]

Possibly. Do you think the knock sensor has a 0-5V output that I could just tap right into?

[BAD LS1]

Should be... They have the plastic KS's in the side of the block just like your GTO.

[PonyKiller87]

Had a tuning lesson with Tom tonight... trucks running great(well other than all of its other non tuning issues, lol), thanks for the help.

[HP ADDICT]

Very cool man!