Any feel like having a tuning discussion?

[Hal]

Feel free to give those of us who are interested, but by no means experts, links to any refrences where we can learn more about this stuff.

Keep the info coming, I like this topic

Like I always run premium gas, have a 5-speed and live in a hot southern climate... I never thought about optimizing an engine for things like this.

[ChevyHighPerformance]

Originally Posted by Hal

Feel free to give those of us who are interested, but by no means experts, links to any refrences where we can learn more about this stuff.

Keep the info coming, I like this topic

Like I always run premium gas, have a 5-speed and live in a hot southern climate... I never thought about optimizing an engine for things like this.

Here is a link to LS1TECH that has other links about tuning.
http://www.ls1tech.com/forums/showthread.php?t=287094

I really haven't read through the stuff listed here but it came highly recommended.

[ChevyHighPerformance]

Just an update. With the new increase in low end torque, I modified the auto tranny shift speed table. This table shows at what MPH and throttle position you want the tranny to upshift or downshift for each gear. I lowered the MPH at which the tranny up shifts and I moved out where the tranny down shifts - I added more hysteresis. So when you are doing 60 MPH and you press on the throttle slightly the tranny doesn't down shift to 3rd right away. I get into 4th gear much quicker now and the acceleration in 4th is fine for small-medium grades. If I need more acceleration, I just blip the throttle more and the tranny will downshift. The stock shift tables can cause you to downshift (4th to 3rd) if you increase the throttle by as little as ~12%.

For low throttle positions I upshift quicker for better (hopefully) MPG. When you need the acceleration the new shift table doesn't hold you back.

[ChevyHighPerformance]

Another update. I've tweaked the tranny shift table several times. Not very scientific but - now it feels like the H3 floats/coasts. Before it always seemed like I always had to press on the throttle just to coast around town (as if I was dragging something behind me).

Also, in my plan the speed limit is 25 (lots of kids) and my plan is pretty hilly. Before I had to press the throttle to climb a hill but to keep speed going down the other side I would just let off the gas and I would maintain speed. Now, I have to press the throttle less to climb the hills and when I go over the peak, I let off the gas and I accelerate down the hill and have to use my brakes.

I know its not scientific, but now the H3 seems "lighter".

[wpage]

Originally Posted by ChevyHighPerformance

Another update. I've tweaked the tranny shift table several times. Not very scientific but - now it feels like the H3 floats/coasts. Before it always seemed like I always had to press on the throttle just to coast around town (as if I was dragging something behind me).

Also, in my plan the speed limit is 25 (lots of kids) and my plan is pretty hilly. Before I had to press the throttle to climb a hill but to keep speed going down the other side I would just let off the gas and I would maintain speed. Now, I have to press the throttle less to climb the hills and when I go over the peak, I let off the gas and I accelerate down the hill and have to use my brakes.

I know its not scientific, but now the H3 seems "lighter".

CHP Good Thread! Kindly monitor your MPG closely as you probe these tests. You are on to potentially significant info. Please continue to share your findings.

[DURAMAX TIM]

I use EFI LIVE for my dmax and it does a great job, hoping that they will work on the H3 soon.

A lot of guys on another forum use it and we trade files, plus my vendor sent me a 500+ RWHP race tune for my truck once the tranny gets upgraded.

diesels are much easier to play w/ AF doesn't matter really.

I've got a tune right now that gives me 60hp and 4 mpg better fuel mileage as long as u stay under 72mph.

It gets addicting playing w/ the tuning to see what u can do, the speed limiter and redline was the first things to change plus calibrate the speedo.

[HOKIE W/HUMMER]

CHP,
I'm really interested in your programming results, so keep the updates coming. So where would an owner search for a reputable programmer that we could trust to develop a "custom" program for our H3?
Hokie

[ChevyHighPerformance]

Originally Posted by DURAMAX TIM

I use EFI LIVE for my dmax and it does a great job, hoping that they will work on the H3 soon.

A lot of guys on another forum use it and we trade files, plus my vendor sent me a 500+ RWHP race tune for my truck once the tranny gets upgraded.

diesels are much easier to play w/ AF doesn't matter really.

I've got a tune right now that gives me 60hp and 4 mpg better fuel mileage as long as u stay under 72mph.

It gets addicting playing w/ the tuning to see what u can do, the speed limiter and redline was the first things to change plus calibrate the speedo.

I know what you mean. I keep tweaking and tweaking when I'm probably way beyond the point of diminishing returns. I'm having fun - I'm a nerd.

[H3.007]

F5 - Are these tunes legit? If so, why wouldn't GM be offering them? I just happened to see a show the other day where an ASE Tech Inspector witnessed an HP test at GM. It was really cool how they did it... Glad to know that such tech claims are third party regulated (kinda like a UL for the auto industry and no offense to GM). This keeps everyone honest...

[wpage]

Having worked for several major Tech Companys. R&D has deadlines and comitments on projects. Often they do not own or have significant interest in products in the pipeline. They kick products out the door. Under the Just in time banner, ready or not. GM has great people however my moneys on CHP to tweak this thing since he has ownership and apparently commitment.
The H3 is still young and has some growing to do...Its a great machine but like the 55 chevy there still may be some tweaking to discover and have fun with!!

[ChevyHighPerformance]

Originally Posted by H3.007

F5 - Are these tunes legit? If so, why wouldn't GM be offering them? I just happened to see a show the other day where an ASE Tech Inspector witnessed an HP test at GM. It was really cool how they did it... Glad to know that such tech claims are third party regulated (kinda like a UL for the auto industry and no offense to GM). This keeps everyone honest...

I know you didn't ask me, but I feel the tunes are legit. I just loaded Alvin's tune (from PCMforLess) and the idle was very smooth and the low end torque boost is impressive (it was much better than my custom tune). Throttle is very responsive down low.

[DURAMAX TIM]

Originally Posted by H3.007

F5 - Are these tunes legit? If so, why wouldn't GM be offering them?

GM and others are after emissions stuff 1st and reliabilty/warranty 2nd (maybe).

got to keep the epa happy.

that's why they have so much torque management off idle, save parts I'm sure.

I know on the diesels it used to be u had to roll out black smoke to make power but w/ EFI we can make more power and very little smoke.

stock Dmax (LLY) is close to 600 rwhp or more w/ tuning and diesel only.
year ago 500 was really tough to get.
but an allison will only handle 350-400 though w/o upgrades.