Tuning for Mild Cam, Headers, etc....

[Davis_1377]

End of your log has some idle time and BLM is 108, which is minimum, so it's taking out fuel and still needs more out.

How you determine that it needs to take more fuel out? My BLM and INT is at 108 so i thought i would have to add fuel to get that back up to 128.

Im reading up on the link you sent earlier also.

[EagleMark]

I've tried a few things on my own like dropping the whole spark advance table to compensate for the less vacuum from the bigger cam. The idle is better when I drop the timming down at a idle but if the rest of the table is still high and after its reved alittle the idle dont fall back down. If I knew where the graph would be good at mabe I can change fuel tables.

That's exactly opposite of what I told you to do in like second post of this thread?

You'll never idle Closed Loop at 60 MAP and 550 RPM. Start at 850, may be able to get it lower later. Idle spark around 22 degrees, stock is 16.

Also note that idle will be higher then this in Park/Neutral, but will be close in Drive.

How you determine that it needs to take more fuel out? My BLM and INT is at 108 so i thought i would have to add fuel to get that back up to 128.

Im reading up on the link you sent earlier also.

Below 128 is taking out fuel because your VE table is to high. Above 128 is adding fuel because your VE table is to low.

[Davis_1377]

Oh I done that before I first wrote you, I thought you was wondering what all I tried.

I used the jet 2 for this if that was the best thing to do. I set the desired idle speed on 850 and the spark table on 22. Did you want the whole table at 22 or just around idle cause I set it there at about idle? At a point it idled up to a part of the SA table i didnt move that was about 26 degrees.

Heres the log I believe the way you wanted. I had to drive alittle to get into closed loop. It has a 180 degree thermostat also.

[PJG1173]

Been looking everywhere to come up with a good Spark advance table or any other things to help. Running a TBI 350 with Headers, dual flowmasters with Comp Cam 12-366-4 Lift: .520"/.515" Duration: 268°/280° Lobe Separation Angle: 113° Has ecm 1227747 $42

If anyone can please help me with any of this id appreciate it. Im kinda new to this but have messed with it quite a bit so theres some smaller stuff i may not know. My map reading at idle runs about 60 kPa at about 550 RPM. Ive tried started working on its idle first to keep a good steady idle and lope but when it does start to lope right it looses its rythm.

this cam has similar characteristics to mine just less valve overlap. if your heads and intake can supply the flow this cam is going to demand at 4500 rpm and above you are going to need more fuel and a bigger TB. also 550 is too low of an idle for that cam 750+ is where mine is set to idle at with 24* timing.

[EagleMark]

Oh I done that before I first wrote you, I thought you was wondering what all I tried.

I used the jet 2 for this if that was the best thing to do. I set the desired idle speed on 850 and the spark table on 22. Did you want the whole table at 22 or just around idle cause I set it there at about idle? At a point it idled up to a part of the SA table i didnt move that was about 26 degrees.

Heres the log I believe the way you wanted. I had to drive alittle to get into closed loop. It has a 180 degree thermostat also.

At idle Closed Loop the BLM is 108, that is as far as BLM will go to take away fuel. VE has to much fuel at idle.

Look in the XDF, use categories and find the hacks, apply the BPW and Spark Advance hack, NOT TPS, and you can see Spark Advance and fueling in data stream.

[Davis_1377]

The first one may be alittle better. I had a good chance to make 2 so I did. Im not sure if its best to do this after its warmed up or both.

[EagleMark]

Logs and tuning adjustments should always be done warmed up.

Logs don't show near enough spark for that engine.

Also IAC counts are very high at idle, turn the screw in a 1/4 turn to open blades a little, with key off. This allows fuel and air to mix better.

[Davis_1377]

My IAC dont have a adjuster if thats what you meant, I have noticed before they were high. Theres a screw for the blades that adjusts the idle but then it will be idling way over 850 I think. I checked the IAC and cleaned it. Heres the results after, idles at desired idle speed even in closed loop until drove then it sits around 1500 RPM.

[one92rs]

I believe he meant to adjust the idle on the tbi on the throttle linkage side. with the torx screw.

[Davis_1377]

Yea thats what I was gonna do but I take that back, Theres nothing to adjust there. Ive seen these throttle bodys have that idle screw but this one has nothing but a shiny spot there with no place for a screw.

[EagleMark]

My IAC dont have a adjuster if thats what you meant, I have noticed before they were high. Theres a screw for the blades that adjusts the idle but then it will be idling way over 850 I think. I checked the IAC and cleaned it. Heres the results after, idles at desired idle speed even in closed loop until drove then it sits around 1500 RPM.

IAC controls Idle speed by adding air, not throttle blades.

I'm not sure how looking at same logs over and over is going to help? I've told you three things you need to do for idle and no change? Spark is same, Fuel is same, IAC count is same... if we ever get passed this there's another 100 things to do.

It's been so long I forget if you have enough fuel to start? What injectors? What fuel pressure? What's estimated HP of engine?

[EagleMark]

Yea thats what I was gonna do but I take that back, Theres nothing to adjust there. Ive seen these throttle bodys have that idle screw but this one has nothing but a shiny spot there with no place for a screw.

Awl or small screw driver, hammer, punch hole, pry shiny spot off and you'll see torx screw.

[Davis_1377]

Ok, I thought you was just pointing some things out, and didnt think you wanted me to do them all at once. Ill raise the spark, turn the screw, and adjust the fuel.

Sorry I had too much things going each day and trying to keep up with all this.

The injectors are stock, Fuel pressure I aint checked. Im not gonna be racing so everthing aint gotta be real perfect at high rpms but still close as possible be nice later. Estimated HP id guess around 250.

[EagleMark]

Did you notice the specs on the cam you have?

HYDRAULIC − Excellent mid-range for TPI
350, injectors, plenum and exhaust system.
2000+ stall converter. Requires custom tuning.
Hyd. Hyd. 2000 to 6000 RPM 12-366-4 268XFI H13 268 280 224 231 .520 .515 113°

Without the higer stall converter, even with a good tune, it's going to be a dead zone off idle... 6000 RPM is going to require a lot more fuel then stock injectors and pressure.

[Fast355]

Did you notice the specs on the cam you have?

HYDRAULIC − Excellent mid-range for TPI
350, injectors, plenum and exhaust system.
2000+ stall converter. Requires custom tuning.
Hyd. Hyd. 2000 to 6000 RPM 12-366-4 268XFI H13 268 280 224 231 .520 .515 113°

Without the higer stall converter, even with a good tune, it's going to be a dead zone off idle... 6000 RPM is going to require a lot more fuel then stock injectors and pressure.

As well as better heads and a single plane intake manifold.......He would be better off to pull that stick out and put something around what I put in my L31 in it.

258/268* @ .006
206/210* @ .050
.458/.458" lift
110* LSA on a 106* ICL

I was cruising about 65-70 mph on the open road today, a/c blasting, listening to some Bon Jovi, rolled on the throttle a little to pass a car while climing a hill, glance down a few seconds later and I was doing 85 mph! Never had even unlocked the TCC or downshifted.

I also running a little late to work the other morning and hit the pedal pretty hard taking off from a redlight on the service road headed into a 2 lane to 1 lane merge.. Gave it probably 1/2 throttle and noticed about 30 mph, I had a floored Avalanche beside me trying to jump in front of me. I had just shifted 1-2, but floored it anyway. 2nd gear from 30 mph, I walked away from a 5.3 Avalanche. All his over cammed, over runnered, high strung, understalled, under geared, small bore 5.3 did is make noise as the old L31 350 pulled away. TORQUE is your friend in a heavy truck.

I was explaining torque to one of the Honda idiots at work and performed a few second gear starts from 0 and never missed a beat there either. With a 2,600 S10 stall its actually a pretty smooth, quick take off too.

Even on my Vortec the throttle plate opening is adjusted for the IAC to only have about 5-7 counts at 600 rpm in Park/Neutral with the a/c off and all the electrical stuff switched off.