Hi Condor, thanks for the reply.

Do you know how many amps going through that switch? Is the main feed to fuel pump also going through the ems and thus the switch? Would it be safer to run it through a relay?

Toni

 

Nice install, I'm considering the FAST EZ EFI kit myself.

 

Hi ToniH

There are 6 wires that lead to the connector to the ems (engine management system)
Orange---fuel pump
Yellow---ignition key (12 volt switched)
Red---direct to battery
Green--- Tach output of amplifier (MSD 6A)
Black---Negitive side of coil if using a ready to run wire distributor, no amp box
Brown---not used.

I am running a MSD 6AL so my green wire goes to it.

The orange wire goes directly to the plus side of the fuel pump. You do not use a relay. the ems is esencially the relay

Yellow wire is 12 volt, I dont know about amps. It is the one where I just put a switch in between the soures (12 volt switched) and the ems.

Red of course directly to battery.

The black and brown I don't use so they are secure.

I used this switch to control a relay to the old fuel pump that I had when the car had a carb. Never had an issue. Now with the PJ III I don't have any issue either. Switch and/or wires do not get hot so I'm guessing the amps are low. I would also guess that the main current and amps comes from the red wire so make sure you use a good gauge equil to the size on the connector. By the way, I took my time and sodered all connections. I have had problems in the past with soderless terminals coming loose. I put the switch on the 12 volt switched (yellow) wire to kill the system, which will kill the pump, did not use the orange (fuel pump) and don't recommend that you do. The ems controlls the pump, you could creat an issue if you are disrupting this circuit.

Hope that helps a little.

Bob

 

Thanks for clearing that up! Very helpful. Makes my job so much easier.

 

Simple switch with led to show on or off. Hidden when ashtray cover is in closed position.

 

Hey Tonih,

You have a great looking Vette there. I went to your web site and really like it. The flairs are something I was thinking about. Maybe later. I see you have a PJ II or so it looks. Mine is a PJ III so the wire diagram I spoke of may be different. Go to www.retrotekspeed.com if you need downloads for the system. It is a great site for information.

 

Condor, thanks for the compliment. Yours is great too.

I actually have PJ I, which is the predecessor of PJ III. PJ II is different design (multiport). Basically I and III are the same but with III they just repacked the EMS into smaller form and integrared it to the throttle body. The software and functionality is the same. When I bought mine they were selling both but I chose PJ I because I wanted a separate EMS so I can upgrade/replace the EMS hardware if needed in future without being dependent on the original EMS manufacturer. More difficult with integrated EMS. Reason for this could be for example: broken EMS and availability of a original replacement zero or maybe some major advance in EMS functionality. The PJ I TB contains no intelligence and all sensors are standard GM parts so the EMS can be replaced with something else if needed. Hopefully I don't have to think this at any point but get long service life out of the major components.

I will check for sw updates on Retrotek's site. I bought my PJ directly from them and they have answered most of my questions this far.

Good solution with the kill switch, I will do something similar.

I see you have a air cleaner spacer, was that needed with a dropbase? Do you have a functioning L88 airbox under your hood?

 

Yes I had to use a short air cleaner spacer. the base of the air cleaner sits a little low and interfers with the fuel pressure regulator. I could of course replum everything and move the regulator but a small (height wise) spacer was a lot easier and less expensive. My L88 hood has a air cleaner cowl box. Gets tons of air from the rear of the hood and off the windshield. The air cleaner fits up in there very nicely. Any higher though and I think I'll run into problems.

I also like the idea of the PJ system using GM sensors. Except for the ems it is all GM sensors and the O2 is easy to get if needed. Bosch wide band readily available. I have already looked at some with the 5 pin connector. about $70 to $80 if needed. All this stuff was part of my research and ultimately my decision to go with the PJ.

After talking to a friend of mine I will drop the torque value down a little in the ems. The reason is because we both think the engine is a little rich with 13.7 A/F. Dropping the torque value is the easist way to see the change. Will do suttle changes like 50 at a time to see what the change is. We both think a 14.2 or so A/F would be much better. Will keep the changes very minor so as to not lean the engine out and cause heat problems.

This is all done in the Dashboard software and is very easy to do. Just another reason I like this system.

Will try and get out this weekend for some more driving. Admittedly I have not driven the car for a long enough period to get true readings. I don't think I have given the adaptive learning enough time to do what it needs to do.

How close are you to making smoke?

 

The PJ preinstalled profile defaults to rich for safety reasons. After you have let the EMS to do the initial self learning for your engine you can lean it out a bit if you like. But remember that best power is made at often around 12.8-13.2 A/F ratio. Tuning the A/F ratio above 14 in part throttle will make fuel economy better though.

I too researched the FI options available and ended up choosing the PJ. Many good features I like, one being the USB link and laptop based tuning software instead of hand held device with small LCD-screen. Also the fact that I can let it auto tune or interfere with my own tuning if I wish. All this sounds so super easy compared to stock C4 ECM stuff. If this works nicely in real life I might get another Retrotek EMS for my C4 and FIRST injection.

I have all the parts waiting for better weather. We still have lots of snow and more coming right now. When spring truly arrives I plan to tackle the install as soon as I can. Also will change the intake from the old Performer to Weiand Stealth at the same time.

 

Thought I would give an update on the install of the PJ III system. I have driven the car and seems to be fine until I come to a stop and the idle goes way high and then up and down. Not real fast but enough where it's very notable. At first I thought I might have an issue with the PJ. Not so. I checked and sure enough timing was the culprit. My centrifical weights were sticking and I guess it was driving the PJ nuts. So to cure the problem:
1-- do not use the ported vacuum port on the PJ, use only a manifold vacuum port and time the engine correctly and then check total timing etc. (Lots of great articles on that in the forum).
2-- check to ensure the distributor is working like it is supposed to.
3-- after all that then adjust the idle, remember on the PJ the front and rear throttle plates must be adjusted equally (50% each)
4-- once that is all done then drive the vehicle so the adaptive learn can start learning.

I guess it goes without saying that setting everything up the correct way and the engine gets real happy. After correcting the timing concerns the engine really came to life. I could not be more happy.

I also have the 3.08 rear and rear suspension parts on now. The 68 really cruises nice. Don't have a mileage figure just yet because of my goof with the timing sucking so much gas. By the way engine runs cooler and very smooth, accerates with authority and sounds great through the super comp side pipes. As they say, timing is everything.

Bottom line; upgrading to fuel injection, with whatever system you fancy, is a real plus. The big lesson I learned is there is a lot of stuff to soak up in terms of reading and understanding various settings and what they do. Be patient, think things through and don't over react if something is not right. It is easy to go into the program and start making changes but that is not always the solution.

 

Very informative, thanks for taking the time to post your results.

 

Hey condor7, are you still happy with your PowerjectionIII install? I'm seriously considering using it for a 383 build I'm working on for my 78. The Powerjection III now has spark control. Are you going to upgrade you setup?

 

Well I won't yank your chain. I started haveing problems with the PJ. Start and idle was fine, never did have an issue with that. For some reason everything would be fine then the system would run so rich it was terrible. I changed several componets and that did not solve the problem. I checked and rechecked wiring and everything about the system and still would do the same thing. I spent more time on the PJ forum reading and stuff thinking that would help solve the mystery. No deal. Got ahold of tech support and they said it might be a ECU gone bad. Could get it replaced for about $300. Good grief.

Well long story short I did magage to get it right. Seems it was a software issue in my program and once corrected the car ran well again.

I kind of had it with the FI. Its great and stuff when everything is working right but I can't and do not want to drag around my laptop all the time "just in case" something goes wrong. Case in point, stopped for fuel, tried to restart would not start. Plug in laptop and sure enough for some odd reason the system went stupid lean and would not start. I basically did nothing for a few minutes except cuss at it and tried to restart. Started right up and running fine ever since.

Perhaps the other systems available are not quite as finicky but this was driving me nuts and I was not enjoying the car.

Well went back to a carb and sold the PJ. Not to worry I explained everything the PJ was doing or not doing and there was no buyer beware crap. I would never do that and hope I don't get it either.

I am back happy with the carb. That does not mean I am not still reseaching the EFI stuff. Thinking about a different system and reading the various forums as well.

I really liked the great start up and other stuff but when it when it comes to being reliable all the time I have serious reservations.

Wish I had a better report card for you. I am not bashing the system because when it worked it was great. Maybe it's just my dumb luck.

 

Properly tuned carb is just as good as EFI, the key is properly tuned and you have to wait 2 minutes if it is cold, big deal I don't drive mine when it is cold.

I get 24mpg on the highway @ 80mph with a Race Demon 825 that flows 975cfm on a 600HP small block, re-invent the wheel I don't care. Have fun with the new EFI stuff the grass is not always greener on the other side of the fence

 

24 Imperial = 28.8 US that is incredible! What is the final drive ratio in 5th on your TKO?

 

Interesting to read of your experiences. I recently had a chance to help a buddy with his Retrotek system and I have to say I was much less than impressed. I've installed several of Holley's systems and it's a LONG way from what they have...even the most basic TBI system (which uses same controller essentially as the high $$ race versions). His did the same thing..when it was *right* it was pretty decent. But you never knew when it was going to go goofy and idle high etc. When it seemed to be running its best, the IAC was basically inactive. Adjusting that overly sensitive throttle arrangement to get some airflow to it so IAC would go back to working correctly when you put it in gear or turned on A/C made it hard to start etc even after resetting TPS and all the other stuff. Tuning it with engine arbitrary TQ values seems pretty weird too. We started at scratch several times and went very slowly through the whole start up process..but it was never what I considered *right*. This was on a very mild near stock 400" smallblock with an auto.

Anyway, we were both pretty frustrated with it. He later got it back to where it was with regard to starting and idling fair..but again..the rest of the tuneabilty was very poor. He's still running it, but the dreams of improved fuel economy etc just haven't arrived.

On the other hand, the Holley's I've done will self tune themselves very well and if you want to mess with them...you can make them do anything you want very easily.

JIM