Faber

idle is at 640 right now. the car is still learning the tune so it feels like it is about to stall once in a while since I only have about 10 miles on it with the idle set this low. Buttometer says it feels stronger, but I have not gotten on it that hard yet.

SlamMan02

(Didn't read the whole thread)

Did I miss the clips?

Did you get a little lope in the idle?
Cause my friend installed Comp. Stage 3s and there is a hint of lope but not worth a grand IMO.

Faber

still tuning for the cams. feels like it wants to make more power down low but something is holding it up. when it hits 2500-2700 rpm it pulls like crazy even at half throttle. the video clip is on the previous page of this thread.

SlamMan02

Nice it sounds sick!Would like to hear some more revs and some driveby footage.

So these are BBRs S1 cams which do not require changing out the springs? How hard would you rate the install, maybe in comparison to the longtube install?

I heard somewhere that BBR Stage 1s are more aggressive then Comp Stage 3s, Can anyone confirm/deny with the specs? How would the lope affect boost with a supercharger?

Faber

The bbr stage one is right in between comp stages 3 and 4. A new spring is recommended but I decided to go ahead and do it without new springs based on the fact that the stock springs are beehive springs to begin with, and coil bind is at 512 lift. These cams are 480 lift leaving plenty of leeway before coil bind. I also talked to chris at blowby and he said they have 2000 miles of strictly dyno pulls on their shop car with stock springs and have had no issues. Also heavy springs play hell with variable valve timing apperently. as far as superchargers go the overlap on the stage 2 cams would steal all your boost, but the stage 1 cams with minimal overlap are actually FI friendly cams.

GT John

The reason for what your experiencing is due to valve overlap. Valve overlap hurts idle and low speed performance by lowering the maniflod vacuum.

Whats happening is you are bringing in more air into the combustion chamber and there is not enough fuel to burn all the oxygen. The closed loop adaptive learn can correct for small errors. ie. dirty or old o2 sensors.

In the closed loop you should start your A/F at about 12.5 - 13.0:1. This can be adjusted through the MAF Transfer Function.

The first thing you will want to do is to datalog the following points.

MAF Counts
MAF Voltage
Short Term Fuel Trims (this is where you will want to see 12.5:1 not 14.7:1)
Engine Speed (RPM)
Spark
Coolant Temp
Intake Air Temp
EGT (exhaust gas temp)

Run the engine up to 1000rpm and hold it there for 30sec, then 1500rpm and hold it there for 30sec, then 2000rpm, then 2500rpm.

This will give the tuner a good idea as to how the engine is performing in the closed loop. He can make adjustments based on this pull.

I know you probably already know this but when the engine is cold the car will start in the open loop mode with timing being advanced. When the o2 sensors heat up the program will switch over to the closed loop.
Dont do any pulls until the coolant temp is above 175deg.

I use Doug at Bama. I went through the same process. I did the data logging in closed loop and emailed it to him. He made the adjustments and emailed the corrected tune back.

I also did a pull at WOT, emailed the pull and the datalog. Doug made changes as necessary and emailed the corrected tune back.

This is a great way to fine tune a canned tune. Dont know why other folks are not using this value added service.

Hope all this helps.

Faber

Excellent info! I am actually helping doug to go a step further than that with the ability to remote control my computer inside the car, and set up, monitor, and deploy new tunes to the car in real time. Very cool stuff!

I was stumped because everything looked great with the tune but something was funky. it fell on its face from 2000-2500 rpm then woke right up and pulled like crazy. I decided last night to pull the throttle body, and give it a good cleaning. it was caked with carbon gunk just behind the butterflies ( i think it was binding up and then opening suddenly which would explain the jumping throttle response). I cleaned it really well with throttle body cleaner and a rag, and pulled the computer offline by disconnecting the sockets to the ecm. when I fired the car back up it was an entirely different beast!!!! WOW! pulled like crazy from 1500 on. I will definately take your advice on the datalogging since I am totally new to that though! I really appreciate that kind of feedback! I love this forum because of guys like you!

GT John

Yeah, I had been talking to Doug about remote control tuning also. Doug's only problem with this, and rightly so, was that some folks just have no computer savy and have no idea what Windoze is.

The remote tune concept would work great. All you would need is:

SCT plugged into the car, SCT plugged into the laptop with internet capabilities, hardwire or WiFi with "Remote Access" set to "Automatic" in Services and a copy of the Pro Racer Package. Doug can access my laptop from where ever he is and make adjustments to the tune.

Doug could custom tune a car from anywhere in the world.

Here in my area, I have made arrangements with my speed shop guys to rent their dyno for $65 for 3 pulls. I havent purchased the Pro Racer package yet because I cant justify the expence.

Believe it our not we here in the St. Louis area do not have SCT tuners of Doug's and a few others experience.

I think that this is a very good opportunity for any tuner to expand their business. Sure would cut down on being away from home.

Happy Holidays (have no idea which holiday)

and

Merry Christmas

Faber

we remote tuned mine using an aircard and remote software which allows doug to have control of my machine (in cases where the user is not savvy this takes the blockhead user out of the equation entirely) we did not need a dyno since i set up a wideband, and he could monitor the datalog in real time. I was driving down the road, and doug was the ghost in my computer...lol. I would pull over occasionally and he would drop a new tune on the desktop, and load it on the car. gotta love aircards!!!! you could use the same concept on a dyno though and have the added convenience of hp and torque gain measurement on the spot as well. I think the aircard remote tuning method is perfect for tuning cars with ram air though since you can measure air fuel at speed.