Projects Track Roadster 16 yrs in the making

Charlie, that's what I was thinkin' when I posted that, that it was the crank pulley clearance issue.
Thought I might have missed something in the translation

I have forgotten what your alt. mount setup looked like though, and was just giving that as an option, as a little "juggling" and the alt. pulley might still be in line with the crank pulley, if the alt. was flipped around.

 

Oops. Well, if flipping it IS a possibility, how about building a "cage" around the pulley to mount the alternator off of?

Something like this, with an additional plate on the front to bolt the alternator up to...

 

This might at least give you some ideas,
Hamber "loud pedal" turned his hemi flywheel adapter into a combo pulley to drive the alternator. Changing the belt required removing the bolts, flywheel to convertor and sliding the convertor back into the trans to R&R the belt over/behind the flywheel. This was a Chrysler extended bell with automatic of course. There's some info here but its mixed in some other threads and elusive but its there. Might pm him if you need/want more info.

 

OK Hambers, I’m back on the TR project. After the alternator meltdown I was fit to be tied, so this last month away from the TR has been a good thing.

Just to recap a bit, before I left we ordered the next larger sized Powermaster unit, which has the same mounting points, to see if it would fit in the nose of the TR, and the answer was… hell no. So that unit was returned to Powermaster.

After multiple phone conversations I was beginning to have some concerns regarding Powermaster based on questionable information I received. Also the unit that failed had been supplied with an incorrect original factory identification tag...hummm. Because of my uneasiness I did a web search and called a few suppliers. I ended up getting an intelligent response and some insights from Mr. Alex Calvo at his company called “Raceproven.com”. This company manufactures alternators for various auto racing teams. Mr Calvo was very accessible and clearly an expert in alternators. I asked about his product line and what he would recommend. His reply really impressed Brett and me. Instead of trying to sell me something, Mr Calvo, asked me to send him the old burned out Powermaster unit before he made a recommendation.

While I was traveling Brett sent the fried alternator to Raceproven. Mr. Calvo made a diagnosis and a recommendation.

Here is his email reply:

”The main issue with your alternator was the poor workmanship and materials used by the supplier. The unit was basically a poorly rebuilt alternator and on top of that the powder coating or paint distorted the ground circuit.

The rotor had a burned out coil, which it is associated to ground issues, the upgraded unit is a completely different when it comes to internal components, as you will see, the 20148 series is base on the NASCAR spec engine alternator and it is build under an ISO 9000-2001 system, ensuring proper assembly techniques and overall the use of true racing grade parts, such as the rectifiers, battery post terminal and its insulator. A rectifier seal increases the rear vacuum effect at low RPM, improving unit thermal cycle during operation at low engine speeds.“

I was extremely impressed with Mr. Calvo and his in depth knowledge and professionalism. We haven’t installed the rebuilt unit but based on my experience so far I would strongly recommend Raceproven.com as an alternator source for any hot rod builder who anticipates unusually high demands on a smaller sized unit. If you have plenty of room for a larger unit or don’t require extra current a standard OEM quality alternator is fine.

It is reasonable to assume that the Powermaster unit had been slowly failing for some time. I wonder if a few of the elusive engine management gremlins could have been caused by a gradually failing alternator, which did not provide stable voltage to the CPU? The best part of this alternator fiasco is that the rebuilt unit will fit…no heroics will be necessary.

As I mentioned above Brett spoke with Mr Calvo at length. Based on his strong recommendations Brett is going to change from one-wire RPM activation to a key-on hot wire activation, which will improve idle output, but will require us to run another wire out to the alternator.

Calvo also wants us to upgrade the charging wire to 4-Gauge back to the battery (we can leave the existing charge wire in place to feed the inside alternator circuit board), he was adamant about this. Interestingly, this is what Brett always does when wiring a new race car.

Mr Calvo was particularly concerned about the alternator grounding properly. His opinion is that the original powder-coating on the case may have prohibited proper grounding. He told Brett that the alternator was rebuilt to racing specifications and will produce 120 amps at full speed, and much better than 30 amps at idle.

The Raceproven upgraded alternator will arrive this week. Now Brett and I have to arrange a time to get back to work on the TR.

Who knows? maybe this experience will lead to improvements in the state of the whole EFI system. I sure hope so.

More as it happens.

trakrodstr
aka charlie

 

Glad you to here some good news!!

 

LB+1,


Thanks my friend. Sometimes it best to step back from a problem.

Stay in touch Doug.


charlie

 

Here are two photos of the newly upgraded Denso alternator as performed by RaceProven.com. My first impression is that I see lots more copper windings. The black powder coat is gone, as well as over spray inside the housing. The terminals are in Dodge Truck lingo "Job Rated"; with big robust terminals that are packaged in race car quality housings and insulators. The unit is now a two lead hookup. The cowling on the back has plug of silicone rubber filling one opening visible in the lower left of the second photo. Altogether a nice looking piece of equipment.

The modifications to the rear cowling are designed to improve airflow and circulation over the rectifier diodes and heat sink.

The fit in the TR engine compartment is so tight that the acorn nuts securing the back cowling are too long (tall) and will have to be replaced in order to hang the alternator back on the engine.

There's not much else to report. Due to busy schedules I doubt that much will get done on the project until the firs week in May.

trakrodstr

 

Charlie, Sounds like you may be back to making some progress on TR. Wish you all the best in getting it up to speed and running.

Hope you have a Great Easter !

Dave

 

Finally there is some meaningful news to report. I’ve been on two trips and Brett has been to Australia and New Zealand in the past month; Brett’s trip was for the company he works for, Aeromotive. Mostly my trip was business but part was for fun. Along those lines I met a fellow enthusiast who is a stunningly good graphics artist and model builder, Bill Gould. He is a big fan of Miller Indy Cars, Model T dirt track cars and hot rods, you should check out his web page at:

http://www.gouldstudios.com/museum_thumb_cars.html

Wednesday evening Brett came over with his wiring toolbox. He ran a 4 gauge wire from the binding post on the new alternator to the battery side of the starter motor. Now there is huge wiring connecting the alternator to the battery. Brett also ran a wire from the ignition key switch to the alternator. Now the alternator is activated as soon as the ignition key is switched on.

You may remember that the front and rear cylinders on each bank were running very low (250 degrees F) exhaust pipe temperatures when we last had the Hemi running. Further, the cold cylinders were running way too rich. In an attempt to equalize the combustion temperatures of the cold cylinders to the normal cylinders (550 degrees F) we decided to drill small air holes in the throttle plates for the four affected cylinders. Brett used a pin vise and drilled a 0.040” air hole in the four plates. A bit more air should result in more complete combustion and hotter temps.

In any case, I installed the four throttle plates in the Hilborn stacks and then loosened all the idle adjustment linkage and “equalized” the throttle rods on each bank so that the four cylinders on the driver’s bank and four cylinders on the passenger’s banke had about 0.005” clearance; i.e., each throttle plate was “open” about 0.005”. We want to get the idle conditions as normal and equal as we can before we try too much road tuning. With luck, some time this weekend, we will start up the Hemi and begin to set the idle parameters and check the exhaust pipe temps.

I’m hoping that the addition of a new high amperage alternator will fix some gremlins and that we can get the exhaust gas temp much closer between the “inner” and “outer” cylinders.

Stay tuned (no pun intended).

Charlie
aka trakrodstr

 

Are you replacing the fuel after the long period of non use?
I enjoyed Bill Gould web page also.

 

LB-1,

Ooops, good point. I'll see to it.

Brett and I had a very productive and promising idle tuning session last night. I'll post details later. Right now I have to run some errands.

Yeah, aren't the Gould drawings fantastic.

more later

charlie

 

As I stated to LB+1 above, Brett and I made good progress last night. To set the stage, all our efforts were focused on IDLE conditions only. After we installed and checked out the new alternator we let the Hemi warm up to full operating temp, which, at idle, is about 190 F<style><!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Times;} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style> °. The electric fan was cycling on an off approximately every 4 or 5 minutes. The idle adjustment was set so that the throttle plates were "cracked" open about 0.005 in.

Once the temperatures stabilized Brett measured the temp of the exhaust pipes about one inch from the flange trying to target the middle of the pipe. Here is what we found:

Driver bank temperatures from front to rear: 180° 900° 500° 200°

Passenger bank temperatures from front to rear: 190° 500° 525° 180°

At this point the engine was idling at 1000 RPM the first and fourth throttle plate on each bank had a 0.040 in. orifice (four plates). The “middle” four throttle plates were untouched.

Brett and I slowly began a process of enlarging the orifices one at a time until we observed significant changes in temperature for example at least 200°F. As we moved through the various trials we kept readujusting the idle trying to keep it around 750 RPM. Each time we were able to significantly increase the exhaust pipe temperature the idle speed would increase. Eventually, we had to set the idle adjusters at zero opening.

We moved from one throttle plate to the next starting at the forward driver’s side stack. The process took about 2 hours. We were also monitoring the O2 sensors during this time and a couple of times Brett would slightly modify the IDLE rich/lean mixture (air/fuel ratio) trying to get the average for each bank at about 13.5:1. Eventually we had to call it a night but here are the last exhaust pipe values we recorded at idle.

Driver bank temperatures from front to rear: 350° 520° 400° 350°
Passenger bank temperatures from front to rear: 340° 500° 500° 360°

At this point the engine was idling at a steady 750 RPM. The first plate on the driver side had been opened up to a 0.070 in. orifice; the fourth plate on the driver side was at 0.048 in. The forward plate on the passenger side was at 0.065 in., while the rear plate was 0.048 in.

We decided to give it a rest. The exhaust pipe temps are far closer in magnitude and we are pretty sure that further “improvements” will result in a faster idle, which we don't want. As the old cast Hilborn system now stands…there is NO idle opening dialed in. In other words, the throttle linkage springs are pulling the throttle plates completely “closed” with no opening or “cracking” of the throttle plates dialed in. See the accompanying photos and notice that this is as "closed" as the Hilborn plates get.

You might wonder…huh? What gives? The answer is that these old aluminum castings and throttle plates were never designed for street use and they leak slightly around each throttle plate (disk); and some air is most likely also sucked in around the throttle shafts. In any case, the temperature values are well with in the acceptable range and Brett set the air:fuel mixture a bit rich (13.5:1) for safety.

So all-in-all a VERY satisfying night of work, both Brett and I were smiling as we wrapped up the evening.

The next step will be to put the wheels back on, get the TR off the jack-stands and take it out on the road. Oh yeah and a fresh tank of gasoline (see I’m listening LB+1).

Each time we checked, the new RaceProven alternator was keeping up with the power demands at idle, including when the radiator fan switched on.

So far, so good; Brett is in his busy season so it may be a week or more before we take the Maserodi on the road.

Stay tuned… Photos show the four throttle plates at the end of the process. The pin vise and the "final" three bits are also shown.

Charlie Little
Aka trakrodstr

 

That sounds like good news Charlie! Bring her by when you're out and about...

 

Sounds like good progress, Charlie! In my mind I'm a bit leery of setting the plates "closed" at warm idle. I hope you don't have any stiction problems at cold startup when the bores have shrunk slightly...

So let me see if I'm hearing this correctly... The center pair on both sides are idling "closed" with NO bleed hole whatsoever? Wow.

 

Charlie, Been a while. Hope that you and TR have nothing but good things so you can start enjoying driving this Hot Rod.

Dave

 

Cool Charlie ! !
Just curious if you shot a temp on the barrels while you were doing all the tuning

 

It would be interesting to see what readings you would get with a uni-sync on each throttle barrel at idle and at 2500 or 3000 rpms. Would the vacuum be the same with all the barrels?

 

Mike,

My pleasure to swing by your place. I hope it's soon. Next week should have some mild nice evenings. Just right for some road testing. With luck it won't be long.

charlie

 

Thanks Dave. Who know? the LA Roadster Show may be a long shot but it's not impossible. Here's hoping I'll be in your neck of the woods come Father's Day.

charlie

 

Thanks for hangin' in there.

charlie

 

31Vicky,

Curious you should mention that. No we have not measured the temp, but that is a great idea; it would tell us if one barrel is significantly hotter that another...good thinking.

I can tell you that after a test run, to evaluate whether a larger bore bleed hole made a difference, it is hot work to remove a throttle plate. You don't need gloves but you can't grip the plate more than about a second, so the aluminum stacks get pretty warm.

I'm running the risk of getting obsessive about Hilborn throttle plates; a sure sign of a weaking mental state...

charlie

 

One Finger,

I have thought about a uni-sync. My opinion, based on anecdotal evidence is that after the throttle plates have opened more than 0.030-0.040" there would be little flow differences between the barrels. A few thousands of an inch makes a huge difference when the throttle plates are "closed" or almost closed; but after the plates are open even a small amount they really allow a major change in airflow. Keep in mind that there is NO intake plenum. Each barrel dumps directly onto the back of the intake valve (about 8 inches away from the throttle plate), so a tiny opening results in a big change due to the fact that there is no plenum to "fill".

The computer software used to tune the Accel EFI module is evaluating the manifold pressure (MAP) because we have fabricated a small "phoney" plenum for this purpose. Also, the computer reports on the throttle position and the exhaust O2 levels. While none of this measures the amount of air flowing through one of the barrels. as a uni-sync would do. In the end, however, the EFI CPU allows us to adjust the end product - the air:fuel ratio. The target being a ratio close to 14:1.

I would be surprised if there were not at least 10% or more variation in the airflow through the stacks at 2500 -3000 RPM. The differences, in my estimation, would have to do with the shape and geometry of the Hemi head's intake runners and so forth; but not due to the throttle plates. However, I do not know any of this from real measurements with a uni-sync, just my best guess.

Thanks for the interesting question.

Charlie

 

Been a while, but have revisit to post 817 & 823 in this thread.

 

31Vicky,

Hummm, it seems that I am repeating myself as I looked back at the earlier posts you noted (817 and 823).

Alzheimer’s, of course, has its down sides; on the other hand every time you speak to someone it‘s for the first time — which means you make a new friend with every conversation.

On a serious note, your earlier analyses were spot on. We did measure the heat signature of the heads from side to side (front to rear) and didn't see much change but the alum is a much better conductor so we need to go back and check the stack temps.

I don’t see that we can do much about the temp of the Hilborn stacks. The heat risers are blocked by the flange and the gastket is extra thick at about 3/16”. One thing to keep in mind is that the EFI nozzles are being fed fuel that is in constant circulation from the tank to fuel rail. So beyond the problems caused by stack assembly expansion differentials (steel versus aluminum) the Hilbon heat signature, whatever it might be, is a fact we cannot avoid with the present configuration.

The engine is idling at 180 degrees F so we don’t want to cool the engine much below that level. There is the possibility of plugging the heat riser port in the head (epoxy) and then making a ¼” phenolic spacer/gasket for the Hilborns as thermal insulation. Unfortunately, if I were to do that then I would have to tilt the air horns wwwwaaaayyy over the valley area and interdigitate them, to clear the hood....think $$$$$$. As things stand the “clearance” between the underside of the hood and the front air horn is about &#8539; inch. Which is why I have ordered two air horns that are ½” shorter to use when the hood is in place.

Hot rods are a series of compromises on wheels.

Keep on sending your thoughtful comments,

charlie
aka trakrodstr

 

Brett dropped by yesterday evening and we worked about an hour and a half. No big deal, but I think we have the idle parameters very well sorted out. Brett dialed in the air/fuel ratios a bit and we were able to open the two Hilborn idle adjustment set screws a tiny amount; probably an amount like 0.010”...I’m not kidding. After we open up the two throttle rods and equalized the cross-over linkage (between the left and right throttle rods) I looked carefully at the individual throttle plates and I could not see any difference, compared to fully closed. Nevertheless, the RPM changed with this very, very slight opening adjustment. Whatever.

Next Brett shut off the engine but left the ignition key on. This let him look over the existing timing, fuel, airflow values, that were established when he fed the CPU a “startup” set of maps (educated guesses). There were some weird values present in the various menus which he smoothed out. At that point Brett had to leave. So we didn’t get to try the TR on the road.

I mounted the wheels/tires and reattached a few accessories like the air horns and so forth. So the TR is ready to go the next time Brett is able to drop by. Just for grins I pulled 4 spark plugs and the electrodes were looking pretty good, but the insulator was black. This is an improvement because in the last two times I looked the electrodes were very sooty. Thus, the idle mixture is much leaner than before. Everything seems to be working as it is supposed to.

The weather is good here so if Brett can find time to work we should be able to do some road tuning.

I hope so.

charlie
aka trakrodstr

 

Interesting results.

Brett came over for a couple of hours last evening. We warmed up the Hemi and took the TR for its first drive in several months. The idea was to work on low-speed partial-throttle operation. For about 20 minutes I putt-putted around the neighborhood and no bad symptoms were noted. The engine starts every time, hot or cold, “on the key” and settles to a nice idle around 800 RPM. After the engine has been hot for a while the throttle shafts bind a bit after which the idle only drops to about 1000 RPM at a stoplight. This has always been the case; and short of spending thousands of dollars on roller bearings and fancy seals, on the throttle shafts, I doubt if there is much that can be done. The aluminum stack castings have different thermal expansion characteristics compared to the steel shafts. I have tried a stronger throttle return spring but it makes driving a pain due to the high effort at the accelerator pedal.

Brett kept taking fuel out of the A/F tables all during this time. The engine never stalled or complained, in fact the whole process was remarkable uneventful. Having gained a bit of confidence that the baseline fuel maps and timing were reasonable we headed for a nearby highway. We drove about 30 min at speeds up to about 55MPH, but always in a high gear so that the engine speed never exceeded about 2500 RPM.

Mostly we cycled going up and down a one mile grade so that I could “lug” the engine a bit on the uphill leg in fourth and fifth gear (5th is overdriven by 75%). The EFI and the hemi preformed very well. No funny stuff and good transitions when making small partial-throttle changes. The car sat several times at stoplights and pulled smoothly away each time. The only strange observation was that the driver side bank was consistently running significantly richer than the passenger side bank. We know this because we have a O2 readout on both exhaust header pipes now. The difference in A/F ratio was especially noticeable at very low RPM (small throttle plate openings).

Upon returning home we were discussing why the O2 values were so different between banks and Brett suggested that we check if both throttle plate assemblies open completely when the accelerator pedal is bottomed out. The answer was — no. The driver side throttle plates were not quite vertical in the bores, while the other side was wide open. We immediately thought of the cross over linkage rod that connects the two throttle shafts. We realized that the linkage arm (hex rod in many photos above) was longer than the center-to-center distance between the two throttle shafts. Which meant that the lever rations were different from one side to the other.

The diagram attached shows the cross-sectional representation of a correctly configured linkage. The length (A) of the crossover rod, which connects the two shafts, is the same dimension as the distance between the throttle shaft centers (B). Assuming the two throttle arms are the same length then the arrangement describes a regular parallelogram and the lever ratios are the same on both throttle shafts; i.e., the throttle plates all open equivalently. As the TR sits right now the dimenion A is about ½ inch greater that dimension B.

To achieve this parallel relationship, Brett will shorten the crossover linkage rod to match the center distance between the throttle shafts. I bet that cures the different O2 readings (A/F ratios) between the two banks. It all makes sense — the passenger side throttle shaft was being opened a bit faster (going leaner at a given A/F ratio) and reached WOT before the driver side shaft.

The cool thing about using the new EFI computer, digital ignition, and harness for the last few weeks is that the modern electronics have provided a feedback loop to diagnose problems with the MECHANICAL side of the system. Specifically, drilling the orifices to help even out idle mixture and detecting the asymmetry between the throttle shafts were both made apparent and “figured out” because of readings by the electronics. Excellent progress.

Next time we hope to test and configure the system for higher RPM ranges.

Stay tuned.

trakrodstr
charlie

 

This is great news. Thanks for keeping us informed and interested.

To me problem solving is what hot rodding and racing is all about.

Good work sorting this out.

Frank

 

Thanks FranK. I’m trying not to get too fired up but the progress has been very good lately. The new alternator appears to be doing its job which may also be eliminating some frustration.

Keep your fingers crossed.

charlie

 

And another step closer !

 

31Vicky,

I think you’re right. This time around the efforts and the outcomes make sense. This feels so different than chasing my tail and getting nowhere.

It did not hurt that yesterday evening was spectacularly nice, perfect for evening cruise.

This is Brett’s busy time of year so I’m not sure when we can try again. It is definitely a two man job...I drive and he enters values on his laptop... nonstop.

charlie