PMO ITB/AEM 2.7L Install Notes

[Knockdown]

Thanks to Al at X-Faktory and Andrew at Rasant, I have received a really nice kit for my 2.7L induction/ignition system upgrades. 40mm PMO ITB's, AEM 506 and Rasant's MIL-SPEC harness, which is really nice BTW.

I intend to use this thread to just post some tips in case the info may be beneficial to someone else in the future.

Here's a pic of the recipient, all in her glorious black primer paint.

[Knockdown]

The kit provided is so complete, one really does not need to do a table top check out, but since I wanted to install later this year, I had to play with it!

The table top setup consisted of a 12V 3A power supply fed by an uninterruptible power supply for the battery connection, a toggle switch to simulate the ignition switch, tied all of the ground connections together on the harness an attached to the power supply return.

One important aspect of the AEM is that when you key off the ignition, it can attempt to save any changes in the ECU memory if enabled in the wizard. If the 12V is removed during this process, it can hose the ECU. I turned this feature off, but still monitored the current when I switched off the ignition prior to removing BATT power.



Having the table top setup really makes it nice to check out the sensors like TPS, MAP, FP, & CHT, and probably more importantly, get familiar with the AEM SW. Plus it's a nice conversation piece when company comes over.

[Knockdown]

To control the injector and coil drivers of the ECU directly, you need to flash the AEM diagnostic firmware into the ECU. After you register on the AEM site, you can download this file as well as your current firmware which you will need to reload when you're done with the diagnostics. Of course you need to save your session file prior to doing this so you can restore that as well.

Once you have the diagnostic firmware installed, you can pulse the coil drivers, I observed these with an o-scope, and the injectors, I just rotated an injector around to make sure all responded OK.

A couple of important points, if you are using a power supply, make sure you have an UPS since if power is removed during the firmware load, the ECU can be hosed and require return to AEM. In addition, make sure the box "keep configuration data" is not checked when reloading your current firmware version, if it is checked, the firmware load will fail.

[Knockdown]

The CIS is out! Next comes the engine bay, shroud, wiring and hose clean up.

[l_turn9]

What fuel pump are you using? And what year is your car? BTW, I installed a BitzRacing EFI system a few years ago - it has a Single TB and I love it but naturally would have preferred the PMO ITBs. Looking forward to hearing about your installation -

LarryT
74 911 EFI

[Knockdown]

Originally Posted by l_turn9

What fuel pump are you using? And what year is your car? BTW, I installed a BitzRacing EFI system a few years ago - it has a Single TB and I love it but naturally would have preferred the PMO ITBs. Looking forward to hearing about your installation -

LarryT
74 911 EFI

I installed Walbro GCL608 awhile back when the old one started leaking, mine is a 77s. Bitz kit is nice!

[l_turn9]

Thanks for the info! After I installed the Bitz I reached thru the Driver's window and turned the key, this was the 1st time I had tried to start it - the engine rolled over 2 or 3 times as the intake system filled up then it started and instantly settled down to a 950-1000rpm idle - I was ecstatic! While I miss the sound of the Webers, I enjoy the consistency and reliability of EFI. I enjoy tinkering and have spent many hours adjusting the MAP. It's incredibly complex as I'm sure you know, but plugging in my laptop and having my mate drive around while I make adjustments is awesome! Will you be setting up the MAP yourself or will someone else do it? Regardless, be patient and be sure to get the idle consistent 1st, then look at all the points of Temperature and RPM. Good luck! Thanks for posting your progress! BTW, I told my Install Story in Excellence. I'll have to look for the issue...

[Knockdown]

Thanks! I hope I know enough to be doing my own tuning, time will tell

[l_turn9]

I'm sure you will. Lots of T&E. Is the AES506 the ECU? If so, does AES provide a manual? Megasquirt offers a very comprehensive manual that tells the details of tuning a ECU from start to finish. I was completely new to EFI when I started and had to go slowly and take it all in. but in the end it was worth it. The Megasquirt manual is on the internet somewhere - it's free and I'm sure Google will find it if needed. It may give a different perspective if need be...
Best wishes for a successful and fun project!

[l_turn9]

Forgot to ask what software you will use to tune the ECU?

['76 911S 3.0]

Originally Posted by l_turn9

I'm sure you will. Lots of T&E. Is the AES506 the ECU? If so, does AES provide a manual? Megasquirt offers a very comprehensive manual that tells the details of tuning a ECU from start to finish. I was completely new to EFI when I started and had to go slowly and take it all in. but in the end it was worth it. The Megasquirt manual is on the internet somewhere - it's free and I'm sure Google will find it if needed. It may give a different perspective if need be...
Best wishes for a successful and fun project!

It is an AEM Infinity 506, and yes, we do provide a very thorough and comprehensive user manual available for download on our website: https://www.aemelectronics.com/files/instructions/Infinity-ECU-Full-Manual.pdf

Originally Posted by l_turn9

Forgot to ask what software you will use to tune the ECU?

Infinity Tuner is the software used to calibrate the Infinity ECU's.

[Knockdown]

Thanks Jayson, good to hear from you! The AEM and Rasant documentation is pretty good. I also took a couple of courses from High Performance Academy that I really enjoyed and found useful, lots of practical info.

[pampadori]

Hi Knockdown,
You're in for a very fun project! I've been enjoying my AEM/Triumph ITB setup for a while now and it has been solid as a rock in terms of reliability.
For the first few months after i got the tune pretty solid I would play with different settings in the calibration - mostly decel, wall wetting, smooth out the timing map, etc. I'm now at a place where I don't really mess with it much at all. I guess its "dialed in" as they say now.

Some things I learned along the way that might help:
1. I struggled getting it to run well with VE based on MAP. once i switched to throttle % it really improved. I believe this is referred to as Alpha N tuning. I also run the ign against throttle %. (technically, MAP is used too but not as the primary)
2. I have changed the values in the "chargetempblend" table. This table isn't visible in any of the out of the box layouts so i had to add it manually in order to change its values. This table dictates whether priority is given to intake temp vs coolant temp (CHT in our cases) to determine charge density. Lower values give priority to air temp, higher gives it to CHT.
3. Wall wetting - I found that I had to run pretty high values here compared to folks with single throttle bodies. If you get the motor running but it refuses to rev up smoothly or If you get lean pops thru the velocity stacks when you crack open the throttles, you need more fuel added via this table. Use your ears and try to get the smoothest, fastest revs by manipulating this table. err...at least that was how i did it.

I enjoyed tuning so much that I almost considered a career change. it was just too much dang fun! Looking forward to hearing updates.

[al lkosmal]

Have fun with the project.....

regards,
al

[Knockdown]

Great info pampadori, thanks, and it is fun, really like having the CIS out!

[cobrar96]

Great info and good luck! I also have a 77 911 S and am curious how this turns out for you.

[Knockdown]

Just fitting the CAM and CRANK triggers. On a 2.7L, you have to grind away some case material at 10o’clock around the new crank pulley. Getting the pin out of distributer gear was stubborn, then I read a 16 year old post from John Walker stating he uses an air hammer. Hey, I got one of those and it did the trick, thanks John!

[tperazzo]

Thanks for sharing this! I'm taking notes for my future engine.

[lvporschepilot]

Rasant's sensor is really outstanding!

[Knockdown]

Thought I would post a pic of the case mod needed for any mag guys out here.

BTW, getting the pin installed for the cam trigger pinion gear is also a bit challenging.