Thread: For Don Shilady

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Don, 2 words. Throttle Valve. A simplified explanation is, The throttle valve (located on the side of the tranny) controls the internal transmission pressure based on the amount of opening at the throttle (or carb) and essentially tells the trans when to do what. From the clamping pressure in the clutch packs to upshifts / downshifts and when to allow overdrive.

If this was not at least close in adjustment, you would've smoked the trans by now. A friend thought that this connection was the old "kickdown" linkage. So he left it off and went for a quick testride. We had to tow him back after 2 miles!

Like you, I think your transmission setup is good.

My AOD uses this same technology and I have mounted a pressure gauge in the dash so I can monitor the trans pressure, by adjusting the linkage length at the carb I can control the pressure in the trans and change shift setpoints.

Gee Whiz, Rodger thinks it is OK and so does 34-40! I am going to include a picture for Jerry out of respect for his experience. I am reluctant to change what seems to be working but when I took the air cleaner off for a picture I noticed the dangling cable. Maybe when I tromped the accelerator I forced the set nut to slide? At present the engine idles at about 1000 rpm. This is the second transmission for this car and the first one locked up due to rust after standing for about five years "dry" in my garage. I took it to a shop that was initially very interested in my car and very helpful. They played around with the first transmission for several weeks with various detergents and pressure tests. Finally they got it to shift through all four gears so I know from their pressure tests that the shift points are determined by pressure. Although the shop got the first transmission to work they talked me into purchasing a new Monster 700R4 and set it up for me with extensive road testing. Now that engine and transmission just went over 1000 miles and unless Jerry can say something full of special insight I don't want to make any unnecessary changes. I do wonder about the dangling cable with the set nut on it. I had to pressure the shop to finally release my car after they had it from February to May 2013 so I will have to go to another shop if there is really something wrong, but I am happy with it running now. Today on a 150 mile trip in my 2008 Impala (V6, 4-speed auto) I watched the tach a lot. In the Impala the tach varied a little more than My Model A but pretty much behaved in the same way as my 700R4. The tach would go up with acceleration but without any large jerkiness over shifts. I think it is OK as is unless Jerry has some keen observation. Yes the Monster trans is set for a very fast shift from low to second and often chirps the tires on that shift. Sooo what does Jerry say about that dangling cable, did the set nut slide out?

For Rodger I did the stall trick and the stall occurs right at 1600 rpm.

Don Shillady
Retired Scientist/teen rodder

While I am glad I took off the air cleaner to see the "dangling shift cable" I already had an appointment this morning for Va State Inspection and I took the car to "Performance Transmission" in the nearby Hanover Air Park. This is a one man shop with Bruce Orlandi who maintains a very neat shop with three lifts. Bruce runs a Cavalier with a 706 cu. in. aluminum block and twin 750 cfm Dominator carbs. He spotted the dangling cable as due to the flimsy aftermarket socket jumping loose when I did the acceleration tests and the cable popped back into place. I have a lot to learn about the 700R4 and I note that my setup includes a Summit accessory to make the OD shift automatic. I tried to understand every aspect of my roadster build but the installation of the 700R4 was limited by a restriction of my observations after the manager of the first shop limited my access to the shop interior claiming I asked too many questions. That shop was interested mainly in treating me as a "customer" restricted to the waiting room just reading magazines. Eventually I got my car out of that shop but there is a gap in my understanding of the car with respect to the 700R4. So far Bruce at Performance is much more informative.

Don Shillady
Retired Scientist/teen rodder

OK Don----I guess you aren't receptive to my ideas of doing the internet diagnosis of your cars problems-------so I'm going to ask for one more thing and then I'll step away from your problems unless you point out that I have miss read the posts--


Get some one to help---can be your wife as this is easy----have her hold the throttle pedal down all the way and then you check to see that the carb blades are all the way open and then under the car see if the throttle pressure arm is at full travel----and also where its at at part/idle travel--------


It appears to me from the photo that you have an linkage setup that is not of correct geometry and/or travel to operate your engine or trans in proper manner----


Lack of travel to open carb= low rpm, lack of travel on trans cable = low rpm shifts, 1000 rpm idle = hanging cable?


And how about a photo of the vacume hose connection for the trans????

Jerry, Thanks for your patience and expertise. I was wondering how/why it was still shifting even though the cable was loose. Although this sort of long distance trouble shooting/education is inefficient I certainly appreciate your expertise. I can check the throttle setting when I get the car back today but I will also see what Bruce Orlandi of Performance transmission thinks of the situation. As you say I may have to reset the throttle travel with the splined shaft on the floor pedal but that will have to wait until I get the car back from Va Inspection. Thanks for your comments. Half a loaf of good advice is better than none even if it is by Internet. I have restricted my comments about the first transmission shop that kept my car for over four months out of civilized politeness but I think you get the drift from what I have said. So far my experience with the local Performance shop is much better.

Don Shillady
Retired Scientist/teen rodder

Jerry, Here is one picture showing two things (I am near my limit on pictures again and I need to delete some). First, my car is now inspected for another year with no change other than headlight adjustment. Second you can barely see the black plastic snap behind the large spring on the shift cable. I will have to check this frequently to see if the little saw teeth in the connector are stripped or maybe I can add a drop of Gorilla glue on it to keep the setting. While "Duane" inspected the car, the Transmission guy at the shop Performance shop ("Bruce") reset the shift cable and took the car for a road test. Bruce is the proprietor of the shop and that shop is really a speed shop judging by the other performance cars there and so far Bruce has been friendly and effective. As far as I can tell, with reinforcement from Bruce, as long as the black plastic snap holds on the shift cable and the set nut does't slip, good shifting should occur. In the photo below you can see the throttle blades in the carb open as held by the wedged weight of a Sears 3/8" drill on the accelerator and the blades are essentially at WOT so there is no problem with the throttle cable. The problem was due to the slipped connector on the shift cable. I now understand that the length of that cable regulates the shift points and that even with it slipped the trans would still shift but much too soon. I am not sure about the hose you mean. The large hose at the back of the carb is for the power brakes coming from the intake manifold. The smaller hose to the bottom front of the carb is for the kit I got from Summit for the OD lock and it seems OK. The idle speed is also now at 800 rpm. Jerry, I would not have found this problem without your question so thanks. Remote debugging is tricky but in this case I had Bruce available to confirm the problem. Even so I really appreciate the expertise on this Forum and your specific detailed questions have been very helpful.

Don Shillady
Retired Scientist/teen rodder

Don------is there a PCV valve in that breather on the left valve cover????????????


And if you remove the black hose from the front of the carb is there vacume at idle????????? or as you rev it up???????

Jerry, I got a chance to check the vacuum port on my carb and there is plenty of vacuum, although I did not have a gauge to put on it. The breather has some sort of spring loaded flap in the part that goes into the valve cover so that must act as a positive pressure device. I understand why you ask relative to the OD lock but it seems that there is sufficient vacuum to handle "positive crankcase ventilation" as well as the OD lockup. The cam from Blue Racer has nearly identical specs to the stock Z28 cam except the lift is 0.010" higher and may actually be a reground Z28 cam. I think the problem is solved as long as the shift cable stays attached. I will put a small hose clamp on that black plastic collar around the base of the shift cable to hold that clamp tight. I will also look for a vacuum "mileage gauge" and maybe I can get to 18 mpg? Thanks for your help and suggestions.

Don Shillady
Retired SCientist/teen rodder

Along the way I found a local Drag Racer who makes a living with a Performance Transmission shop about two miles from my house. I am amazed by the neatness of his three-lift one-man shop and he provides excellent service. Because he is a one-man shop you have to make an appointment but when you get there he is friendly and efficient with fair prices. Anyway he has several pictures of his cars on the wall and since the early part of this thread featured Indy cars contributed by Jerry Clayton I will add some pictures from the Richmond area. The second car is owned and driven by the shop owner Bruce Orlandi. It is a fiberglass 2002 Cavalier body with a 706 cu in Gene Fulton aluminum V8 running a 4.10 rear and the transmission was built in Bruce's shop. Bruce's car has run 4.58 seconds in the 1/8 mile drag and 7.20 seconds in the 1/4 mile. His brother Vince runs a black Trans-Am in the first picture and is often slightly quicker. Bruce keeps the 4.10 rear gear as a compromise for 1/8 and 1/4 mile tracks. Anyway I hope to lean on Bruce's friendly expertise from time to time since he is so close.

Don Shillady
Retired Scientist/teen rodder

For What it is worth this can be my personal journal in case no one else reads it. First, thanks to Jerry Clayton my car shifts better now. The engine idles at 800 rpm, the low-to-second shift occurs higher at about 2500 (usually) and amazingly the OD kicks in a little sooner so that the engine runs at 1800 rpm at 50 mph and even at 60 mph it is about 1900 rpm. Soooo, I took my little 63 mile test drive up to Bowling Green (Va) and back for the same path/route as before. I tried to fill the gas tank into the neck of the tank and then fill it to the same place in the neck after the trip stopping at the same gas station. Unfortunately this time I only used 3.800 gallons for exactly 63.0 miles which gives (63.0/3.800) = 16.5789 mpg or about 16.6 mpg. This time the front tires were set to 32 psi and the rear tires to 30 psi and I used 87 octane gas. About 1/3 of the tank still had 89 octane in it so it was 2/3 87 octane at the fill up. So what did I learn from this? First there was no noticeable pinging on the 87 octane mixture which allows me to use cheaper gas. Second the shifting seems more normal now and varies from about 1800 to 2500 rpm during normal traffic shifting with 1800-1900 on level highway driving at 50-60 mph. My conclusion is that I am probably going to average about 16 mpg with this drivetrain but I can use 87 octane gas without pinging. One other item is that my digital odometer racked up exactly 63.0 miles for the same path my 1998 Sunfire said on its' odometer.

Don Shillady
Retired Scientist/teen rodder

That's good progress Don. While the total MPG is relatively unchanged - you've learned some more about the car and it's worth the smiles per mile! 8-)

More mpg

Just for the record I finally decided to change out the high Zn break-in oil at 1147 miles and after a three day survey of available oils I "invested" in AMSOIL ZROD 10w30 because it seems to have the right amount of ZDDP for a flat tappet engine and I was impressed by the anti-rust data Amsoil shows. You may recall my first GM 700R4 rusted up sitting without fluid in my garage through several seasonal cycles so my unheated garage is not without moisture. Just to add this the engine would not start yesterday until I added a containter of HEET drygas to the tank and dribbled gas into the carburetor several times. Apparently there must have been some condensation in the carburetor bowls but after I dribbled gas into the open carburetor about five times it would roar to live briefly and then shut off but after five tries I must have dragged whatever moisture was in the carburetor through the system and got gas flowing. When I got the oil change I also got the first lube of the front end since it was built in 2005 and it does seem to steer easier now! However when the shop checked the trans fluid it took about 3.5 quarts of trans fluid! I had noticed the trans shift-chirp from low to second was gone so I guess all that saved my "new" 700R4 was the DeRale extra capacity trans pan, whew. Anyway what looked like just a small drip from a hose from the radiator to the extra trans cooler was probably more of a squirt at highway speed and I was losing trans fluid. The fix was to add a second hose clamp on the conection to the auxilliary trans cooler under the right front fender. So I had to make my usual 63 mile run up to Bowling Green Va and back to test three variables at once (the scientific method suggests testing only one variable at a time!). The tires were all set to 30 psi or slightly higher due to the innacurate gauge on the air pump and I expected the 10W30 to have less engine friction than the previous SAE 30 oil. Mainly I wanted to see if the level of trans fluid went down over a 63 mile trip. Soooo, after taking the same tried and true pathway and filling the tank into the neck of the tank before/after, I used 3.667 gallons of 89 octane over the 63 mile trip. Thus (63/3.667)=17.18 mpg, the best so far! As far as tire wear goes I think the constant low-to-second chirp will wear out the rear tires before the question of inflation pressure becomes important so I am going to keep the tires at a nominal 30 psi. The best news is that the trans fluid level is the same as when filled now so I think the second hose clamp to the auxilliary trans cooler solved the leak! One other comment is that the 63 mile trip is mostly in OD gear with only minor town driving actually in Bowling green (two traffic lights) and a few other lights between Route 2 and Route 1 so the mpg will obviously be much less for in town driving but hey, at least I inched up over 17 mpg for sure with the 10W30 oil and staying under 60 mph for the whole trip.

Don Shillady
Retired Scientist/teen rodder

Don,
After reading your last two posts I will offer you two comments:

First, regarding your assumption that since you noticed no pinging during your economy run, then you can run 87 octane fuel without any concern. Since you were on an economy run, one must assume that you were driving very conservatively, i.e. the egg under the throttle approach as opposed to multiple pulls at full, or close to full throttle under load. The time that pre-ignition rears it's head is not at cruise, but under significant load, and it will be worse with hotter ambient air due to decreased density. IMO your experiment is flawed relative to assessing your required/needed octane level. Sure, you're safe to run 87 octane if you're staying out of it, but if you want to know if that lower octane fuel is OK under load then you must test under load.

Second, your assumption that your first to second "chirp" is going to wear your tires quicker than having them over inflated simply does not make sense. The higher inflation pressure decreases your tire footprint, wearing the center portion of the tire on every revolution of the tire, and even more if you happen to "get on it" from a standing start, drive curvy roads, and even with your first to second "chirp". In fact, you will likely find that your "chirp" will diminish as you approach the full footprint inflation pressure for your rear tires. Over inflation leads to shorter tread life, decreased traction under load, plus it significantly lowers your g-force traction in corners. Taken to an extreme, severe over inflation is a significant safety risk for highway driving in areas where you are dealing with "fun" roads with lots of hills & curves.

I understand that you will likely choose to disagree with both comments as you believe that you have "proven" your results, so let's consider them as alternate information for anyone else who happens to read your "personal journal" looking for ideas with an open mind.

I recently took mine out for a 100 mile trip (200 miles round trip) to test my mileage under different throttle conditions, on the way out I drove between 70-80 mph (as traffic allowed). Now mind you I have a bit of a heavy foot and two 4 barrel carbs, and I run top grade 91 octane. On the way out 100 miles I averaged 12-13 mpg.

Coming back I dropped the speeds and was careful with my foot, ran between 65-70 mph for about 60 miles and averaged 13 mpg. But here's the surprise!, when I dropped the speed down and stayed at 50 mph for the remaining 40 miles I averaged over 40 miles to the gallon!

Course that's not making any allowances for the tow truck's mileage……………

Seriously Don, stop trying to analyze everything, drive the car and have fun!

.

Hello Rodger and '36 sedan. First I note "I used 3.667 gallons of 89 octane over the 63 mile trip" as stated above. Due to moisture in my garage I may have to use HEET several times in the winter. I avoided the 87 octane on the latest "test" worrying over the amount of ethanol in the 87 octane thinking there might be more hydrocarbon in the 89 octane. From several thermodynamic discussions I have read the mileage may be increased due to the heat content of the fuel and it is well known that ethanol fuel runs "cooler" so there may be added mpg in a fuel which contains less ethanol. On the other hand the octane rating depends on the slowing of the combustion process which may depend on more ethanol in 89 octane fuel. It is not clear to me whether 89 octane has more or less ethanol. Then some folks say that the highest octane is less frequently sold and stays in the ground tank longer and may have more water in it. Anyway Rodger, this latest test used 89 octane and I changed several variables at once but the result is slightly higher mpg. For '36 sedan, I am all too familiar with the better mileage on a tow truck already! Further you ('36 sedan) are totally correct that my mpg tests are the most fun I get these days so I try to think of new tests. However this time the test was motivated by the desire to find out if the trans fluid leak was fixed and evidently the added hose clamp did the trick. So the bottom line is that my wife commented that the car never seems to be finished but that is fine with me because the major changes are done and only "fun" tinkering is left. Each "test" is mainly motivated by "what test can justify a 63 mile jaunt up to Bowling Green and back and the satisfaction that I am driving a machine that I constructed mostly by myself" with help from others here and there over a ten year period. Jerry Clayton's idea of a later model small block will have to wait until the necessity arises.

Don Shillady
Retired Scientist/teen rodder