What's goig on?

[Bill Musarra]

I have a strange situation that I am throwing out for comments. I have finally gotten my engine alive with the FAST XIM and XFI system. This is a distributorless ignition system. It incorporates several sensors for engine management. Throttle position, MAP, cam sensor, and crank trigger sensor, wideband O2 sensor on the right bank of the exhaust. I have fired up the engine several times and let it run to get temps up. I say several times as I am still running down grimlins. An oil leak here, a gas leak there etc. so the runs have either been short or long. I noticed yesterday that a strange phenomena has arisen. The exhaust on the left side of the engine have now taken on a nice copper color, which I expected. The number three cylinder has gone on to a little bluing. On the right side the exhaust has not turned copper yet, except for one cylinder. The temp of the two sides is noticeably different. on the left side the temp is high and on running the engine at 1500 rpm with the idle screws starts to glow. The right side is noticeable cooler. I am temped to place the O2 sensor on the left side to see if it changes things. There is a bung there as I was going to eventually run EGTs just to know what they are. I would bet they are too high and need investigation. The engine idles pretty good as I am not sure how smooth it should be. The cam is a Comp cam, but I don't have the numbers of the grind. Just remember it is a hydraulic roller with roller rockers. Numbers on the engine are:
351 Windsor. bored 60 over, stroked(can't remember the number) and internally balanced. Have guessed that it is around 392 ci. Heads are AFR 205s with TWM 8 port FI. The distributor has been hacked to run the cam sensor. 8 coil packs from Chevy Corvette and MSD plug wires. Plugs are Autolite AR39. The engine warms up nicely when run long enough at idle. Fuel pressure is right at 40 lbs. Oil pressure is at 50 lbs.
I plan to take the car back to the installer of the ignition system for some other repairs. The alternator is heating up to the point that it is cooking the belt after several minutes of running. So that needs addressing. When I first got the car home from the ignition install I noticed when replacing a fuel line that the alternator wasn't even hooked up(had to remove it to get to the line). When the installer hooked it up he didn't refire the engine or put it on the computer, which he will the next trip. Last fireup was on the battery to check for leaks after repairs. Still have an oil leak that will have to be replumed with a new line.
Do any think I have something to worry about?? Suggestions??

Bill

 

[Bill Musarra]

Bringing this up to the top of the new post line so others might get a look at it and hopefully post a comment before it gos to the shop on Wednesday. Thanks

Bill

 

[Keith]

Take it for an "Italian Tune Up" and then compare....

 

[Ian Anderson]

Are the injectors individual or batch fired?

If batch fired swap the 2 leads over and see if the "hotter exhaust" move

I'd also check for air leaks in and around the inlet
With engine at idle spray around injet loints with carb cleaner, easy start etc - when it gets drawn into an inlet via a leak the idle will rise

Lastly are all your slip joints on the collectors sealing correctly? If not they will draw air in as well as let exhaust gasses out - when they draw the air in it will give a wrong reading on the O2 sensor

Ian

 

[EGLITOM]

Hi Bill

Sounds strange to me. Is the wideband sensor used for permanently optimising the A/F ratio ? If so there should be no difference if you put in into the left or right collector because on 180° crossover exhaust two cylinders of each bank are feeding into one collector . Do you have "knock" sensor on both banks ? and if so, are they used to control (retard) the timing ?
If you have sequential injector timing, does it fit with your firing order ?

And one last thing i could think of, are you shure that your engine builders has build identical CR ratios on both banks ?

TOM

 

[Paul Thompson 'Hooligan']

Hi Bill -

I see you say you picked the rpm up with idle screws but I assume you have monitored the airflow into each stack at idle with a meter - I've seen engines where an imbalance on idle choke / flow settings will cause noticably different temperatures across a motor...

Just a thought.

 

[Bill Musarra]

Thanks for the input. To answer the questions and what I have found out from the builder:
Keith,
I am assuming you mean to do a Lemans type run to clean every thing out. The car isnot on its feet yet. Still working out the ever mindful gremlins.

Ian,
The intake of the heads and the intake itself are from the factory. The only action taken was a match porting of the heads to the intake and it was not a full port, Just a little more than a match of the openings. The injectors are individually fired. I will try the starter fluid to see what it does, but I don't think this is the culprit. The exhaust system is secured at the end of the mufflers to the trans. Nothing is loose or sliding, so doubt there is a leak..

Tom,
The wideband sensor is for the whole shebang. I don't know if there is a knock sensor built in. FAST website is having problems and I get run time errors when trying to get on. I can get on specific pages of the site, but if I try the home page the error pops up. Will keep trying and quiz the builder. My engine was built by Charly Peppers in Hall county, He is a rather unique individual. He is an older fellow who does all his work in a barn on his property. He has been building engines for the racing comunity for a good number of years. His work is definitly upper crust. He does a lot of the 7 liter cars for the drag racers in the southeast.Atlanta chassis dyno built the upper end of the engine for me. Brad Brand is a long time drag racer i the sotheast and was the first Outlaw division racer to bread the 200 mph barrier. He knows his Fords.

I have a side issue that has to be addressed along with this problem. The alternator has gotten extremly hot(after several one minute runs to check for leaks etc.) and is shredding and boiling the belt. It has been removed and will go for a test this afternoon to confirm its integrety. It was inspected prior to install several months ago and came out fine. It is a high amp unit. It has at the same time caused the pully on the alternator to become magnetized!!??

I called Brad this afternoon and he told me that if the butterflys are not set equally on each bank, the side with the opendings wider, will cause that side of the motor to run the engine and the other side to lean out or not get sufficient air. I will reset the throttle plates to zero and restart the process. I will also try a few of the suggestions. I had planned to drive the car for a while and take it back to Brad's shop for a full chassis dyno tune. With the alternator problem, it looks like I will be back sooner than expected.

I appreciate the collective effort from you guys. I will report back what is discovered.

Bill

 

[Bill Musarra]

Paul you posted while I was writing my response, and what you say is basically what Brad was saying and has the simplest explanation.
I believe I once saw a simple device that would measure flow from the vacuum created for setting multiple carburetors. As I remember it, it was a water tube arrangement. Anyone remember such a devise? Not even sure if this is correct?

Bill

 

[Jac Mac]

Have a gut feeling your alternator or its associated wiring/hookup is the issue here Bill, struck it once before in a job I was involved with and once the alternator gremlins were fixed everything fell into place. Unfortunately I was not privvy to what the actual problem/issue was in that dept.

The magnetized pulley could be the key, to induce a magnetised state there would have to have been a large DC field around it, although that could have happened to the pulley prior to assy.

 

[Andrew Robertson]

assume ignition timing has been checked on at least number 1 but ideally on all 8 as you are running an 8 channel ignition and some ECUs allow individual trim - may be a setting awry there somewhere.

also no real point doing a lot else until all 8 stacks have balanced airflow at idle and throttle linkage is reset after synchronisation has occurred. Then make sure you have no weird individual fuel trim programmed into the ECU and that AFR is set to give fastest idle speed for a given throttle opening.

I agree the alternator thing sounds super wierd - maybe you are driving into a partial short and drawing heaps of current. How much current is your total system drawing from the battery while the car is running with the alternator disconnected? Unless you have electric water pump etc you should be below 10 amps all up with lights and wipers etc all off.

Cheers, Andrew Robertson

 

[Pete McCluskey.]

I suspect it is the balance of the butterflies, and their is a device to measure vacuum so you can balance them. I have one but cannot remember where I sourced it from, I'll check it out when I get home and post it for you.
This is probably a less likely reason, but stainless exhausts will take up that golden colour if sprayed with a lubricant like WD40. I used to spray my bikes exhaust because I liked the look. So if you have cleaned the pipes or wiped them using a lubricant the colour will vary dependant on the amount of lubricant spray used on each pipe.
That assumes they are stainless of course.
I found it its called a syncrometer.It works with efi as well as Webers. Go here.

WEBER CARBURATOR SYNCHRONIZER SYNCROMETER.

 

[Jack Houpe]

Bill, I tried the corvette coil packs with my electromotive EFI they have built in amplifiers and did not work at higher RPM. The problem you may be having is not in fuel air but timing. After removing the coil packs and using the individual coils I believe I showed you at RA my problem went away. If the Fast system has been using these coil packs then disregard this message. But the coil packs are triggered with a 5V positive pulse from a GM EMS as were most other systems fire the coils by ground. I have electrical diagrams of your coil packs if you need them PM me your email address.

 

[Bill Musarra]

Last night around 6:30 we solved all the problems(I think). But you know about Gremlins!!?? I worked on the car for a day or two trying to fix a pesistant oil leak and a few other minor things, and then took it out to the shop that installed the system. I also roamed around the FAST web site. They make their system for the LS1 Chevy and like to use their coils. Just had to add that feature to my setup, which they had done. The guys at Brad's shop(Atlanta Chassis Dyno) fixed the oil leak at the oil filter. The fitting was an old one and on the 37 degree face there was a flat spot. I guess you have to be careful in buying stuff on Ebay!! So that was cured easily enough.
The first problem to be looked at was the alternator. They found an Electric shop that thought they had the cure. It was over in Monroe, Ga. about 30 miles away. Took it over to them. It is a little town where guys sit around talking in the main bay and one guy does all the work. Can't beat small town living. They, or rather he, tested the alternator and it came up pretty good for a 200 amp unit. He told me that since I had so much power eating equipment(electronics) that the system was trying to charge the alternator to hard and it was overriding the system, as everything was wired properly. What he did, was to convert the alternator to a one wire system. Changed the regulator and that was that. Tested the alternator and it read better than before. Hooked it up to the engine and it worked perfectly. No overheating.
The next problem was the exhaust heating issue. I had a small hand held temp sensor from Harbor Freight that I use for some HHO experiments that I am doing(on hold til the car is finished), and after fire up of about 30 -45 seconds of idling, got temps on the drivers side of 250- 300 degrees. On the passenger side temps of 90- 120. With a good temp sensor at idle after several minutes it was 380 or so vs.150-180. So we redid the butterflys(again). We were getting one set of the butterlys that would not match the others and appeared closed while the others were open. It was also running very rough. Rougher than ever before. Fiddled around with it, but the temps stayed the same. We then pulled the no. 1 plug on the driver's side and observed it firing with the fuel pumps off. Its arc was very weak. The plug was virtually clean as though it had never been fired(it was also the coldest cylinder). We tried an MSD coil he had with no improvement. We tried a few more things to see if it was in the harness, but they checked out O K. Upon closer inspection, we found a piece of metal in the head of the plug. It was sooo small that you could barely see it. Picked it out and reinstalled it. Then one of the fuel pumps would not run. For the next half hour we tracked it down just to find that we were looking at the wrong pump. In checking things someone had caused the wiring to become disconneccted. While the guys were looking at the plug situation I fiddled with the butterflys and got the one bank to open on the baseline. When we connected the fuel pump and started the engine, it ran smoother than it ever had. The temps on the passenger side were reading 280- 300 at idle, and the pipes are starting to turn golden. So I trailered the car and came home. Now I can finish hooking up the few wires that have not been hoked up for a while(accusump, tail lites, oil cooler and other minor things), install the seats and a few other things and I will be on the go(I hope).
So I want to thank all of you for the info you supplied. It made us think and ultimately led us to the conclusions that solved the problems. I doubt many would use as much electronics on their cars as I have, but it is what I wanted, and realized it would have a few bugs. Actually more than I expected. So thanks again for your imput. Now to get this thing finished.

Bill