Hi Folks,
This morning I received on of those good news bad news phone calls.
The bad news was my Dyno slot for Weds had to be canceled (again!) for a real paying customer. The good news was, I had the dyno today till 12 noon if I wanted it. Need I say anything more?
Project TJ Kompressor is now done for the most part. In a moment I will be summarizing the results and giving a few well deserved thank you?s.
Last week I shared the initial Horsepower and Torque reading as a result of bolting on the Avenger Super Charger right out of the box. I was and still am quite impressed with this unit. It worked well, but like anything else I wasn?t fully convinced, after visiting with my friend Joe, that I had everything I could get out of it.
Here are the final results after tuning.
Tuning by Wire
I?m certain none of this will be new to some of the young folks around here, but you don?t tune engines like you once used to. Jets? What are Jets? Vacuum Advance? Advance Curves?
None of the old ways of tuning an engine for peak performance and reliability apply to a computer controlled engine.
At the advice of my friend Joe, and a new friend, Huge from the ?land down under? I ordered a ?Fuel / Ignition Timing Controller? from Split Second. This unit comes with it?s own 2.5 Bar Map Sensor and allow full management of the Fuel Injector Bandwidth and Ignition Timing (in retard mode.)
The unit also allows you to take control of the O2 Sensors when in Closed Loop mode AND Boost pressure is being generated.
The FTC1 is a black box I have hanging from the underside of my hood just above the stock PCM.
I will snap a picture later when my camera gets home.
It isn?t much to look at, but wire it up and connect it to a laptop to be programed it and it?s amazing what you can do with it.
I am not going to go into all the details of how to operate and program the FTC1 but will briefly explain how it works.
For more detailed info you can go to
www.splitsec.com
The FTC1 lets you ?condition? the signals going to the Jeep?s PCM to reflect actual engine conditions WITH the Blower Installed, by sending signals the PCM can understand.
Why is this of benefit?
Well the PCM was initially used and programmed to control a normally aspirated engine. (no boost pressure)
Now with the super charger in place, the sensor signals being sent represent greatly different actually values, then the values that would be there without the super charger being installed.
In essence, the FTC-1 allows you to re-map your fuel injector bandwidth a ?plus or minus? approximately 50% of the range it would normally be operating in.
Larger Injectors, and more air pressure dictate the need to do this.
For ignition timing the FTC1 allows you to selectively retard timing based on engine RPM and Boost Pressure.
Both maps, Fuel and Timing are adjustable using a laptop, which plugs into the FTC1 and the R4 programming software supplied with the unit from Split Second.
Fuel maps are adjustable across the entire Vacuum and Boost pressure range, in my case from ?28.5Hg to 0 Vacuum (in 1 Hg increments) all the way up to 0 to 7.5 PSI of Boost (in 0.5 psi increments).
Individual adjustable increment can be made in 500-RPM increments.
Think of a rather large spreadsheet, with Vacuum/Pressure at the columns and RPM at the rows.
The cells in the middle represent the values you wish to be sending/adjusting to the stock PCM.
Talk about being able to fine tune things!
Timing works the same way, Vacuum/Boost along the top columns, and RPM along the side rows. Only with Timing the values of the cells represents the number of degrees in timing ?retard? you would like to ?subtract? from the engine at any given RPM and vacuum/boost range.
Later I will see if I can capture a couple of screen shots to explain this a little better.
The End Results
The following two charts reflect the performance of my 97 TJ 4.0L before the super charger, after the super charger, and after I tuned it ?by wire? using the Split Second FTC1 ? Fuel / Timing Controller.
Peak Horse Power
Peak Torque Power
Horse Power Curve Comparisons
Please note, I only have the data on the Horse Power curves for the Stock Engine and the final product, after the Super Charger and After Tuning by Wire (Using FTC1 from Spilt Second).
While I ran the Jeep for the super charger alone on the Dyno to get peak HP and Torque readings, I did not record the data for the Super Charger alone after just bolting it on.
Why?
Well, I am getting the dyno time for free, (when it is available) however, each time a recording is performed there is a $75 licensee fee that I must pay. That is getting expensive folks. Read that, ?I?m getting cheap in my old age.?
So, sorry but the funds are not unlimited. Thanks for understanding.
That said, here are the Horse Power Curves from just prior to the start of this project, and those that exist now.
Torque Power Curve Comparisons
Here are the Torque Curves.
As you can see from the results I have there is a significant increase in both Horse Power and Torque.
Was this an easy installation?
Well the bolt on part was, and for $3,800 I would have been quite pleased with it. Having spent the additional $500+ on the Split Second FTC1 controller however made all the difference in the world in drivability.
Prior to the FTC1 it was indeed powerful, now it is powerful and SMOOTH! Every bit as smooth as my other current other vehicles, which came from the factory with super chargers on them.
I?m happy with the results. Time will now tell if there are any negitive side effects as a result of this change. I expect there will be, as adding more boost and more fuel into an engine has to have some effect on its longevity.
How much? I don?t know.
Other Closing Thoughts
Air/Fuel Ratios
Using Joe?s guidance, and a borrowed Wideband O2 Sensor I tuned the FTC1 for fuel to match Joe?s recommendations based on Boost pressure.
I had to reduce the injector bandwidth for the vacuum portion of the engine, as the 26 # injectors where causing it to run rich.
I fine-tuned the injector bandwidth for the Boost Pressure portion of engine performs, however, these changes were minimal. It was indeed surprising how well the stock PCM allocated for this, especially once the 2.5 MAP sensor was add to the system.
While not reflecting exactly how I have all 200 adjustable cells set up, here is the guideline I used to get the A/F ratios correct.
Target Air Fuel Ratio?s as follows:
Vacuum/No Boost = 14.7 to 14.0
0.1 to 2.0 psi = 13.5 to 12.7
2.1 to 4.0 psi = 12.7 to 12.5
4.1 psi and up = 12.4 to 12.2
Boost Levels
The highest boost I recorded was 6.7 psi Absolute above atmospheric pressure, however this level of boost pressure is very rare with this system.
The highest boost pressure occurs in the early morning, when air is the coolest, and humidity levels (dew point) are at there highest.
Under full throttle (absolute Wide Open Throttle, No Load Conditions) boost routinely hits 4.0 to 5.3 psi, even at 85 degrees F
Fuel Mileage
After installing this system and driving my Jeep for a total of 3,200 miles I have a pretty good expectation as to what to expect on fuel mileage.
It has gone up, even with a heavy food on the skinny peddle.
Prior to the Super Charger Installation my MPG for the previous 10,000 miles of driving was 14.8 MPG.
My worst tank (not off roading) was 13.52 MPG, and my best was 16.23 MPG.
After the Super Charger installation, but before the Tune by Wire Exercise,, the first 1,862 miles brought with it an average of 15.54 MPG.
Worst tank was 13.71 MPG and best 15.93 MPG
After the Super Charger and after the ?Tune by Wire? effort mileage went up again to an average of 15.96 MPG.
Worst tank was 14.70 MPG and best was 17.86 MPG (all highway 65mph.)
Please note: These MPG figures, after the Tune by Wire effort are BEFORE the dyno tuning done today. If over time these numbers vary significantly I will post them.
I can live with those numbers, even if I have to use High-Test fuel now.
Closing Thoughts
Would I do this again?
?I? would. But please understand, I have done similar installation in the past. While not an expert by any stretch of the imagination, I did have a fairly good idea what to expect and what would have to be done to resolve some issues.
I would do business with the folks at Avenger Superchargers again in a heartbeat.
Their support has been terrific and constant throughout this project. When I needed to talk to someone about a technical aspect of this project Jack was always available and in no rush to get me off the phone. The same I can say for Ed and his support in other matters.
I paid $3,800 for this blower on a pre Moab Easter Week sale. I would do it again in a heartbeat.
I am convinced that ?tuning of the PCM and a MAP sensor capable of reading not only vacuum, but also pressure is required to get the most power out of this system.
However, I am not at all convinced that this tuning can be done by a super charger manufacturer and shipped with the blower. It just doesn?t make any sense to me, there are far too many variables.
Perhaps some level of vendor supplied PCM tuning can improve performance over no tuning at all, but given the different levels of performance experienced by multiple Jeeps with the same bolt on blower I have to conclude (at least to my satisfaction) that variables on each Jeep require individual tuning. One size fits all just doesn?t seem to be workable to me. (Just my opinion here.)
The 26# injectors shipped with this kit are more then enough to fuel my 4.0 L engine. Or so it appears.
I have a feeling larger injectors are being installed to address issue ?symptoms? without dealing with the real issues. I believe based on what Joe showed me the issue isn?t injector size as much as it is ignition timing being to far advanced during certain parts of the RPM range and certain boost pressures as well as air temps being too hot..
FTC1-019 ? The FTC 1 was custom built for my installation (engine size, boost pressure, ect.) There was a two-week wait for this unit to be delivered. It was to come with a starting set of both Fuel and Ignition timing maps for my installation, but for some reason it was shipped without these.
Being I received the unit on a Friday night I had a weekend to play with it in my shop. This was a bit harder to do then I though.
I fired off an email to Huge, who I met online as a result of this project. Huge was kind enough to send me a copy of his Fuel and Ignition Mapping tables to use as a starting point.
As I found out later, Huge is located just south of Sydney, Australia.
Thank you Huge, your mapping tables got me going down the Tune by Wire timeline in a much faster way.
I played with it for a week, extracting out as much power as I could perceive based on the seat of my paints, then I finished it up on the Dyno.
All in all I was able to get almost full power (up t the last 11.2 hp and 15.2 ft-lbs of torque) in my driveway without the dyno.
I have one more trip to the dyno scheduled for next week, to see if I can tweak this a little more. Once I am done, please be expecting a file with my Fuel and Timing tables.
I do not know how they will affect your Jeep and Super Charger Performance, but hopefully they will be a plus for you. (I?d like to repay your kindness in helping me out if I can..)
That?s it for now folks. I am certain I will have a few more comments to add as time goes on.
My next project will be to sand my hard top smooth, fill the fiberglass seams smooth and then Base coat Clear coat it the same dark green as my Jeep body. Fix the roll damage and dents too.
Why?
I like being different (and I need a project to keep me out of trouble). Besides the soft top is about to go on for the summer anyway.
Frank