Projects Track Roadster 16 yrs in the making

Not to waste everyone's time with a lot of lame posts....but I just got back from a 40 mile "lite" cruise and all was well. Lots of stop and go traffic and city driving a couple of miles on the freeway at about 2,000RPM in 5th gear (about 65mph or so). Nothing to report so far, which in this case is good news.

The next step will be to equalize the two throttle shafts and the begin tuning in the higher RPM ranges.

Cheers,

charlie

 

Charlie,
Another thing you may be seeing with the difference in A/F bank-to-bank is the tendency of one set of butterflies to "shade" the airflow at part throttle. This is a little tough to explain, but once you look for it, it makes sense.

The throttle bodies are mounted at an angle to each other, to match the port angle of the heads. The plates open in the same direction, but the ports flow air in opposite directions. The plates on one side of the engine will block the natural path of airflow slightly until you get to about 50% throttle.

I set mine up so the plates open away from each other (called a Z linkage), but this is an insufferable pain in the ass, and there is NO way to perfectly equalize the opening rates.

I wouldn't get too worked up about tuning the last bit of difference out of it, as this may be the root cause....

 

Maybe this will help... (maybe not)
http://www.kinsler.com/Cat_32_Pgs/Cat_32_4_09_Pg_62.pdf

 

ex,

Right you are. I agree completely. The RPM range were were focusing on the other day was between 1000-2000. At such small throttle openings there is little flow but lots of turbulence, I imagine. The asymmetry you describe above is probably not as pronounced at low RPM compared to higher ranges. So I think we can do a little better. But you are correct that at WOT there is bound to be different flow patterns; my understanding is that Brett can deal with that, a bit, by varying fuel on a nozzle-to-nozzle basis.

By the way, one can cure the z-linkage imbalance by going to a jack-shaft type linkage, but they’re kind of clunky looking if you ask me, and take up lots of room.

Thanks again for your perceptive comments; that’s what this Forum is made to accomplish.

Cheers,

Charlie

 

Actually, WOT is about the only place they will flow evenly, as the plates are 90deg to the bore on both sides. Bottom line is, they just weren't designed for great part throttle mixture control...

I don't have room for the jackshaft assembly on mine , but luckily it's a race car, so I can live with the part throttle imbalance.

 

A quick update.

Last night Brett and I “shortened” the cross-over linkage rod that connects the right and left Hilborn throttle shafts. We removed 0.45 inches of length; luckily the threaded bore, which receives the spherical rod end, was deep enough to tap a bit deeper to accommodate the thread loss when we cut off the 0.45“ piece.

Once back together we confirmed that the throttle plates open in synch and that they both advance to full WOT (the plates are parallel to the bore of the stack). The accelerator pedal, when depressed fully, also achieved WOT.

One more tweak that is completed.

I had an OMG moment last weekend with the Hemi died abruptly while idling in my driveway. I tried to start the engine with no luck even when the Hemi had cooled down. I was so bummed that I just walked away. A couple of days later Brett showed up and looked around and noticed that the ignition coil lead to the distributor was completely out of the socket. It’s hard to see because the coil is hidden down on the bell housing and the coil wire exits out the bottom of the fake Vertex mag body. In any case, the insulator boot was too small and had slowly squeezed down and worked itself off of the coil nipple. So my fears that new gremlins were appearing was unjustified. Sometimes it really is the most obvious...duh.

I hope to drive the TR a bit this Memorial Day weekend. Nothing fancy or long distance, just some putt-putting around KC.

Shake hands with a veteran.

Charlie

 

This post is going to sound like a broken record. The engine EFI tuning was going well until about two weeks ago when the Hemi became very hard to start (overnight). Quite a mystery but we began a series of trials to isolate the variables one by one. Not the ign switch, not the batteries, not the EFI computer as far as we can tell. The spark at “start” seems weak so I ordered a new coil (the old unit was from a earlier Petronix distributor conversion).

On the other hand we really have made progress with idle combustion uniformity across all eight cylinders and with throttle transitions when driving in city traffic. The Accel EFI is much more flexible and allows for noticeably smoother drivability at at partial throttle.

I keep hoping the TR will get out of the “experimental” mode and move on to the “go out and use it mode.”

I’m not sure if any of this is even worth posting, but I figured some of you Hambers have hung in there and I owe you an update. I’m bummed I missed the LA Roadter Show once again.

Trakrodstr
aka charlie

 

You'll get there, I'm sure of it.
You could just put 4 bbl or two on it but wheres the adventure in that.

 

I'd be bummed too after this long. Hope the car isn't destined to be forever in the Experimental mode with more bugs than an exterminator could ever handle.
That would be discouraging.
Hope it gets better.

 

Charlie - I am learning to eat my desert first - You have so much on your plate - Lunch
time will be over before you get desert! De tune the (M) and drive it on down the road.

 

I could install a 4 bbl, but I would have to cut a big @#$%! hole in the hood....those Hilborns are about eight inches lower than a 4 bbl.

 

Blue One,

Yeah I got too much ego in the game. This will turn out to be a weird “quirk” not a fundamental issue. I just get cranky too easily sometimes....

Doug, I’m trying to chill-out, but this deal is like the old southern fable about the tar baby, I am stuck so hard I can’t let go.

Brett on the other hand is much more business-like. He is certain we will find some trivial reason for this new wrinkle. The good part is that all this BS happens in my driveway, not out on the road.

I should emphasize that if you drove the TR now, versus this time last year, you would be amazed in the difference.

Hangin’ in there...

charlie

 

Charlie,

What's that phrase about building a car? The first 95% of the build takes 5% of the time and the last 5% takes the other 95% of the time. Keep on keepin' on.

 

Yup, always remember it was running fine, and something changed... I've dealt with this for years with the race cars. People with the best intentions will come up and tell you: "Your problem is that you're using part X." Well, part X had been on the car for 10 years and working fine.

You'll get it sorted, and then all the planning you put in will pay off...

 

A couple of days later Brett showed up and looked around and noticed thattheignition coillead to the distributor was completelyout of the socket. It’s hard to see because the coil is hidden down on the bell housing and the coilwire exits out the bottom of the fake Vertex mag body. In any case, the insulator boot was too small and had slowly squeezed down and worked itself off of the coil nipple. So my fearsthat new gremlins were appearing was unjustified. Sometimes it really is the most obvious...duh.

I wonder if these two instances could be related or actually the same problem.

 

M-X-1 Shake Down

 

Rick, exwest, Vicky and LB+1:

All you guys, thanks for the constant encouragement!

IT WAS THE COIL!!!!

Hooray. We jury-rigged the new coil just to test it during a start cycle and the engine fired before the first revolution was complete.

My guess it that the coil was progressively weakening and the last time we started the car it barely worked; but once started the coil had enough grunt to run the engine.

The next day the coil did not have enough energy to fire the plugs — IN THE CRANK (KEY) POSITION — due to the drain by the starter motor.

In fairness the old coil was made for an ignition points and condenser based system and not a modern digital capacitive discharge ignition system. It may be that the new electronics damaged the old coil. I don’t know.

In any case the news is good. The new coil (rectangular shape) will fit in the old space (cylindrical shape), Brett is fabricating a new mounting flange and I should be on the road this weekend.

Good news for sure.

Thanks again for the interest.

charlie

 

I know that this may sound crazy, but could you put it on a DYNO for an hours worth of "test & tune"? I drive by a 'tuner' place in Merriam that has one. Just so that you can tweak it with out having to go 'drive it' around the block and then 2 days later it has issues.

Just a random thought outloud. And if you do check into it, tell them your situation and I bet that they will help you out ($$$) in their 'downtime'.

Chris

 

Dry firing that coil can't be any good for it. Even if that wire was 2/3 of the way out has got to cause some harm no ?

 

Charlie, your old coil may have needed an external resistor. Many of them can be damaged by running constant 12V input. Just a thought.

 

Chris,

Your thought doesn't sound crazy at all. Brett has mentioned he wants to get the TR on a chassis dyno to make the final tweaks. But you may be right about just going straight to the dyno.

Merriam is certainly close to home and work. Thanks for the suggestion.

Charlie

 

Good point. I hadn't thought of that. The new coil has it's own fancy silicon rubber boot so the wire will not squirm out in the future.

Another good point. When we installed the new distributor and CD ignition we removed the resistor. In retrospect I should have just bought a new coil, but the old unit worked pretty well for a while. Live and learn.

It was sure good to here the Hemi fire up with the new coil.

Now if we can get the new coil mounting bracket finished...

More soon I hope.

charlie

 

Just spent a couple of days on-and-off reading this entire thread from start to current. What an amazing journey and captivating story. I admire your tenacity and openness, it makes the messages crystal clear.
Your comment that you've had to learn more than you ever wanted to know is dead right by the look of it,...but taken you to a place in the knowledge tree you may not have ventured by desire and that's both a plus and the essence of hot rodding huh!
Anyway...I had a thought which may help, may not. You (and others) have made a huge input into designing around the shortcomings of the Hilborn stack injectors. I have some experience with those in a racing midget application where we (dad and I) modified a Corvair to run a Hilborn-style constant flow injector.,...see below.

This was a highly experimental one-off custom deal we did for fun and on a budget...But what we did learn was alot about construction and tuning. The stacks were made from steel tube on the bottom while the tops were made from aluminum with steel shafts and brass butterflys. Butterfly shafts were three short shaft with connectors per bank to allow for movement. And yes things moved around when it got hot so we set the air gap at the butterflys at .001" Idle was okay, but not really a concern as it is in your scenario.

The point is: I know that on factory triple carb setups the end carbs have thicker butterflys for better seal than the centre carb...to promote better idle. Yours appear to be thin aluminum...so why not make thicker ones from brass?...Not now...perhaps a special project at some point in the future?
Machining these is a piece of cake? Just make a mandrel the right diameter, machine the end of it at 7 degrees, mount a piece of brass of the right thickness to it and then turn to final diameter. Remove the brass from the mandrel and it'll have the required angles. (not sure if it was 7 degrees)



That's it in a nutshell, just thought something we learned may assist dunno, over to you.
In the meantime keep up the great work...you're a true inspiration and proof, nothing is impossible!

 

nzhotrod, how do you cool that Corvair? Alcohol?

 

Yes, it ran (still runs) on 100% methanol.

 

OK Folks, I thought I'd write an update post and then respond to the fascinating message from "nzhotrod" (below).

Regarding the latest changes: THAT'S WHAT I'M TALKIN' ABOUT!

I've driven the Maserodi about 300 miles this weekend and it has performed flawlessly. The drivebility is excellent. Far beyond any driving experience thus far. The Hemi starts on the first revolution of the crank and idles at about 600 RPM when cold. After the engine has heated up to normal operating conditions the idle is about 800; mainly due, I assume, to expansions variations in the stacks and throttle plates.

The engine is remarkable flexible and smooth. It will pull from 1500 RPM in fifth gear without stumbling and the air:fuel ratios stay close to 13 or 14 to 1. I haven't really nailed it hard yet. I want to wait until Brett is along for the ride with his laptop hooked up.

I haven't checked the mileage, but I can tell that the engine is getting far, far, better miles per gallon — at least twice as many MPG as before. Which ain't saying that I'm getting good mileage...it's just not getting ridiculously shitty mileage.

The local ambient temp got up to above 92 degrees F (33 C) yesterday and I sat in some really long stop lights with the electric fan buzzing away — the engine temp never went above 180 F (82 C). The engine would start immediately after a full heat soak cycle.

While it may be too early to declare victory, all the indicators are that Brett has finally wrestled this EFI beast to the ground. The advent of the new more powerful alternator, the new coil and all the tweaking of the linkages and air bleed holes has made a phenomenal improvement in the overall performance of the Hemi.

My plan is to drive the TR as much as possible. If the present happy status continues I'll make a few 200-300 mile trips around Kansas and Missouri. Assuming the local trips are promising I will try to get the roadster out to "visit" my 50 year car buddies, John and Steve, in SoCal. We will see...

Hallelujah.

charlie
aka trakrodstr

nzhotrod,

Man O' Man, your Corvair engine fuel injection system makes my Dodge set-up look like a walk in the park. I would love to see the beast in the "flesh". Oh well, not too much chance of that...unfortunately.

It appears as if you and your dad both have ingenuity as a middle name. I have to be honest; I didn't fully understand your discussion of the brass throttle plates and how the finished parts related to the mandrel you spoke of. I'm not a machine tool guy. I should mention that the Dodge Hilborn throttle plates are thick aluminum; while the early DeSoto throttle plates I spoke of are thin steel. In any casy you are correct that in factory 3x2 bbl setups the front and rear carb throttle plates are thicker. I have a set of Rochesters for a Dodge Hemi (Offy intake) and the "end" carbs have noticeably thicker throttle plates.

You are too kind in your comments about my role in dialing in the stack EFI system. I will accept that I refused to deviate from my vision of a user friendly stack EFI set-up — but the heavy lifting, knowledge and creativity rest solely with Brett Clow. He deserves the praise and credit. I will pass along your words of praise.

The most satisfying part of this journey is that I am now in a position to advise other hot rodders who wants to run a stack-based EFI. So if any Hamber reading this post knows of someone who is thinking of such a project have them get in touch with me. Brett and I can save them some time and $$$.

By the way nzhotrod, do you follow the Indy Car series? Scott Dixon gave the field a driving lesson at Detroit and damn near won at Texas last night. The more a race course places demands on driver skill the better Scott Dixon does. You New Zealanders must put something in the water. So many world class drivers from such a small population.

Keep up the good work and give your Dad my compliments too.

charlie

 

Sounds like you're about to pass go and collect 200 huh! Well done.

We always keep an eye out for Scott Dixon, he's a class act and 'll be sure to pass your regards on to dad...he'll be chuffed.

In the meantime I'm sure you'll be coming home with bugs in your teeth....comes with driving with a big grin!!! I'd love to hear the motor run....(current project has a 241 Dodge hemi).
Best from down-under.

 

Now, you're talking, a 241 Dodge, the jewel of the Mopar Hemis. I have some vintage 241 racing boat engine parts, a vintage Clay Smith cam ( with the snout) and two original mid-50s Offy 1x4 bbl alum intake manifolds. Also, you likely know that a chap in NZ is selling modern alum intakes for the little DeSotos, which are readily adaptable to the little Dodges (slightly diff flanges). There is also a chap in Florida who is selling a 2x2bbbl for the low deck Dodge Hemis: http://www.vintagespeed.com/

Let me know if you are looking for any specific items. I don't part with my Dodge and DeSoto Hemi equipment to make money but to make sure the parts go to good homes and get a new lease on "life". I've had some of this stuff for almost 30 years.

Please keep us Hambers informed about your 241 project.

charlie,
aka trakrodstr

 

Thanks for your reply, info and kind offer...I don't want to sidetrack your thread but here's a brush-stroke of what we're up to:

The 241 is my first hemi and so far a I like what I see...progress has been slow, just reading, researching and collecting parts. Recently I got some momentum going and mocked up the motor...


I thought if it could make 1HP per cubic inch as a street motor I'd be happy

Lately the emphasis has been of body and chassis... you can follow progress on our Forum here...http://www.nz-hotrod.com/vbulletin/showthread.php?4857-New-Project-The-Grasstrack-Deuce
And recent updates start here on page 11:http://www.nz-hotrod.com/vbulletin/showthread.php?4857-New-Project-The-Grasstrack-Deuce/page11

..and a bit more over here: http://www.deuceslimited.com/index.php/topic,1208.0.html

 

NZHR,

I jumped to your New Zeland Hot Rod Mag Forum. Nice project. You really have to be dedicated to put up with all the hassles of distant parts and supplies. My hat is off to you as a hands-on fabricator, designer and builder.

A quick story about Wilcap that I think (old age) I covered earlier in this thread. I bought the tranny adapter and flywheel for my TR from Wilcap probably around 1998 or so. Tony Capanna the grand patriach was still dropping by the shop, which was run by Tony’s son, Lloyd. I knew that Tony was a Bonneville and Indy legend and had the privilege of speaking with Tony by phone, as he was helping out in the office the day I called. What an honor. After I hung up the phone I remember thinking I should buy a plane ticket and a voice recorder fly to Calif. and “interview” Tony for posterity. How I wish I had...

A couple of years later Lloyd died suddenly and Tony passed away not long thereafter.

I guess my point is that your flywheel is a direct lineal connection to Tony’s 1958 Red Ram Indy car...cool!

Good luck with the little Hemi. Below I have pasted a link to the History page of Wilcap’s web site.

charlie
aka trakrodstr

http://www.wilcap.com/webdoc7.html