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Thanks! This is a great help. I can put this in my CAD program to take the measurements. My exhaust pipe has the heat shield and was cut just behind the bend before the resonator with a 2″ pipe welded in behind.
Jim”
Thanks! I am anxious to fire this thing up, but still months to go. I have all the ancillaries to deal with: carb, fuel pump, radiator, starter, generator, water pump, etc.
Looking at my mufflers it looks like the original pipe from the manifold was 2 1/4 and cut at the bottom of the bend, probably to replace the first resonator. Seems like a crowded space near the fuel pump, do you know what the dimensions of it were? Presumably less than the 6″ diameter like the two behind it? I have routed my auxiliary electric pump lines on the outside of the frame because of the vapor lock worry.
I do plan to wrap everything with the high temp manifold wrap, I cooked my wife in the Packard years ago because the pipe passes under the passenger side, she wasn’t a happy camper so I did lot’s of insulating after that.
I appreciate your comments, I do want to make this car very quiet between the hydraulic lifters and muffler system.
Thanks again!
Jim
What a wonderful piece, very unique. I’m forwarding to my Studebaker friends (yes I have a couple but I try to avoid the subject).
Jim
I’ll use the basic dark body color for the fenders (tempting as it would be to have them a different color) and just use the lighter color for the belt moldings including the ones going under the doors and along the rear fender attachment per the scheme shown in the ’35 brochures. The fenders are pretty straight with some surface rust and minor bends here and there.
I think the luggage rack is supposed to be basic body color, but I am tempted to use the lighter belt molding color.
As for my double ended engine stand – it is crude and I’m not too proud of it so not too many pictures. “Mission adequate” and that’s all. Basically it was built out of two regular engine stands bolted together with steel angles and straps. The older one had already supported Chrysler 383 and 440’s cantilevered from one end.
The problem was how to support the engine with the bell housing installed and still be able to convert it into a rotisserie for working on the engine alone. I built up a separate wood support to do that which created Chinese puzzles to convert back and forth. The upper left picture is when I pulled it out in 2004. The lower right shows the back end installed.
this kluge got trapped between the hoist and the front end of the engine when I needed to remove it, so I had to disassemble the engine stand while it was hanging on the hoist.
In 20/20 hindsight and feeling really stupid, I could have easily used the four post lift to do this whole thing by hanging the spreader bar and engine from the garage door end of the lift and use the lift to raise and lower to remove the engine stand, wood frame, and then roll the chassis underneath it using the four post lift to lower it in. Duh!
I guess bottom line for others – if you have a way of using a chain hoist instead of an engine hoist it will probably go much easier.
Yup, bolt bending is a real worry, greatly increases the stress. When I first pulled the engine in 2004 (upper picture) the head was off and I used a couple box beams across the head studs to reduce bending in the studs.
When I installed it last week, the cylinder head was installed and torqued, so I had to find another way. At the front which wasn’t so heavily loaded I used a light box beam bolted to the water outlet with a chain hook between.
At the back taking most of the weight I used hooks bolted solid to the lower bell housing/engine bolts (grade 
.
The calculations say this had very large factors of safety, but still a worry when you actually do it. The hooks claimed 3700 lb capability each.
In reality a 1/4 inch Grade 5 bolt could take the entire weight of the engine and then some if loaded in pure tension or shear – it’s those bending forces that will get you such as the hoist beam.
That might have worked, it would have solved my first problem of wrestling the engine off of the double ended engine stand. I think the problem coming from the side is the front tire doesn’t allow the engine hoist to get far enough forward to clear the transmission when you bring it in.
In 20/20 hindsight I could have used my 4-post lift to hang the engine from – duh!
David: I figured you meant 1200 lbs and you well could be right.
I probably put too much faith that there was a big safety margin in the simple minded 1/2 ton rating painted on the side of the hoist. If this was airplane world I guess it worked per design – no permanent deformation up to design limit load, permanent deformation allowed but no failure between limit and ultimate (1.5 x limit). 1200 lbs would be in the bad lands between limit and ultimate.
Jim
Bill, the problem I had with the hoist was that the engine hoist jack ran into the front cross member of the frame before it got back to the engine mounts. Leaving off the transmission and power brake/free wheel unit probably would have moved the cg of the assembly far enough forward to get the engine a bit further back from the hoist and avoided the problem. I took the whole assembly out in one piece 12 years ago and I guess it was too long ago to remember the problems. I didn’t want to wrestle with engine/clutch/transmission separately in the car. The body was off last year but I had to put it back on because I don’t have enough room with them apart, either the frame or the body had to be left outside.
Jim
Sounds like a hacksaw is the plan! Thanks, Jim
Roy Martin
“The Temperature Gauge Guy”
172 Laurel Hill Drive
So. Burlington, VT 05403
802-862-6374
I don’t think he does email. He doesn’t do electrics or motometers. He doesn’t really advertise, and I only found him by way of a 2010 forum posting on AACA.
This Pierce has always spurred my interest since by coincidence as rare as it is it happens to be an 845 Club sedan like mine. Every now and then I haul out DVD’s to get inspiration to keep going on my rough heap. The Pierce should get top billing in these shows – although the repro Gee Bee air racer in “Rocketeer” maybe should share it.
I think the most shots of the car are actually in one not mentioned, an obscure low budget movie “Just You and Me Kid” with George Burns and a young Brooke Shields. There are a lot of shots as George drives it around including parking at the grocery store and putting orange traffic cones around it. To spur more prurient interest at one point Brooke Shields hides naked in the trunk/spare tire compartment. Having the same car I often wondered how she ever fit in that narrow trunk, skinny though she was. Looking at the DVD on the big screen it looks like they probably removed the rear seat and built a larger false trunk compartment into it.
It is so obscure that it wasn’t available on DVD until a couple years ago but it is now available through Amazon. They only burn a copy when someone asks for it – not in stock for immediate delivery.
Jim
Yes, check that the pressure relief spring isn’t broken and that the plunger moves freely. I had a brand X go to zero oil pressure due to a tiny burr on the pressure relief valve plunger. My Pierce oil pressure relief valve spring had one pit of corrosion that likely could have caused the spring to collapse dropping the oil pressure. I found a near replacement that requires an extra shim washer. I had to buy ten so if you find you need one let me know.
Jim
I still think these issues could be related to the start of Studebaker control and the new 8, unless the knowledge out there is that ’29’s and ’30’s had no more issues than previous years.
I know next to nothing about ’29’s or the Gemmer box, but it doesn’t stop me from speculating like everyone else on 200% of what I know. I don’t think the general excuse that all cars had material defects and quality control problems really explains this. If the Gemmer box bearing races are truly “pot metal” -a hard but brittle material that might wear well but prone to brittle fracture – it seems like an avoidable poor choice of material. Obviously much superior materials and quality control for bearing races and housings were available at the time, witness the Timken roller bearings used for wheels and differentials. Even the Fafnir spring shackle ball bearings seem to be more a problem of being a bit undersized and subject to attack by corrosion rather than being brittle or defective. They also were designed with a failsafe – if the balls crumbled the shackle pin was still trapped in a hard steel washer.
The comments that other luxury cars like Cord L-29 used the same basic steering gear doesn’t strike me as a roaring endorsement.
Pierce had to rely on outside vendors like Ross and Gemmer to supply steering gears, and it seems there may have been lapses in vetting the design and testing of these with the turmoil of 1928-29. One can imagine the chaos of crashing the engineering, management and process systems of two car companies together simultaneously with developing a completely new engine and car in a very short time while the staff is wondering what the organization chart is going to be over the coming year. It would hardly be surprising if with a very short fuse Pierce put the pressure on Gemmer to deliver something fast at reduced price to please the “new broom”. Any new design has teething troubles and issues that must be worked out, this is compounded by re-organization and compressed time schedules. My speculation.
Jim
Poor metal in the steering gear and bad axles in 1929 coinciding with the takeover by Studebaker in 1928 and large increase in production. Coincidence or was this level of failure common at that time?
Jim
Greg, I hadn’t thought about it but you are right, the jets are the same for both branches, so it doesn’t seem they were intentionally compensating for the difference in length with the jets. Reading a little further in the text where I found the distribution data (“Internal Combustion Engines” by Polson 1942) the main factor for the duplex manifold was to minimize the tendency of the heavy fuel drops to not reverse course as the different intake valves opened and closed. With an outside intake valve open it establishes flow down the length, then when it closes and an inside valve opens it forces the flow to reverse direction and the heavy fuel isn’t going to reverse with it, thus the outside cylinders tend to run richer than the inside cylinders if they aren’t split up.
Trying do all the inter-related calcs for airflow, AF ratio, heat loss would be very challenging. Better to just measure it. A thermocouple in the exhaust would be ideal, but just slapping one on the outside of the manifold and driving at a fixed condition long enough for the temp to stabilize would probably answer the basic question. Come spring I may do that on the Packard.
The change in airflow is simple to approximate without measuring for our purposes, at a fixed RPM it is going to be pretty close to proportional to manifold pressure. I tend to think in terms of fixed RPM, because I spend a lot of time trying to stay at 65 mph as I go up and down hills, so the speeds and cooling airflows are constant. Manifold pressure in turn will be pretty close to proportional to indicated horsepower =brake horsepower + engine friction. With sea level pressure at 29.92″, an engine cruising at 15″ vacuum has an absolute manifold pressure of 14.92, or approximately 1/2 of sea level pressure and 1/2 of mass flow.
Approximating the performance of the Pierce 385 Eight from the 323 ci inch Eight in the text book, at 2400 rpm and 60 mph (with an overdrive or tall rear end gear), the max indicated power will be about 158, friction hp 38, for a net max brake hp of 120. At 60 mph level road power will be about 45 bhp+38 engine friction hp = 83 ihp, and that should be around 14″ vacuum and is in the vicinity of a net 1/2 net airflow compared to wide open throttle.
Jim
Greg, for some reason my full reply didn’t get uploaded, too much verbal diarrhea!
It would be interesting to measure EGT. Years ago I was researching valve seat recession and found that the exhaust valve temperatures at maximum speed and power were virtually unchanged from the 1930’s to the 1960’s. The reason is that low compression ratio increases exhaust gas temperature while high heat losses reduce it. Compression ratios increasing from 6 to 10 were offset by the lower heat losses of compact OHV combustion chambers after WWII leaving measured peak exhaust valve temps about the same at ~1300 to 1420 degrees. The peak gas temperature should be 100’s of degrees hotter than this.
My assumption that exhaust temp would go down at WOT is based on some data of various engines showing a valve temperature drop of 250 deg going from 15/1 AF ratio down to 12.5. I measured my Packard at 8/1.
In the ideal cycle the EGT is first a function of AF ratio regardless of throttle, maximum at stoichiometric going down richer or leaner regardless of mass flow (throttle/manifold pressure x RPM). In the real engine the EGT drops below ideal from the heat losses to the cooler cylinder walls, valves, exhaust ports and manifold. Higher mass flows have more heat loss but less temperature drop. Whether the EGT drops with increased throttle at constant RPM is a balancing act between the increased mass flow increasing temperature against the richer mixture cooling it after the booster opens. The actual change in mass flow between cruise power at fixed speed of 60 mph and max throttle is probably only on the order of 2/1, and my guess has been that the heat transfer of an engine with fixed coolant temperature and thick cast iron walls is going to have less effect on EGT than an 8/1 AF ratio – but that is just my guess and I could be proven wrong, it wouldn’t be the first time!
Meanwhile I found an interesting tidbit (well interesting to me anyway) of data from an early ’30’s straight 8 engine, probably a Chrysler Imperial engine. The measured variation in AF ratio at a low speed was as high as 16/1 on #2 and as low as 11.6 on #6. It probably would have been better at higher speed (I assume the low speed of the test was dictated by the limitations of the instrumentation). At any rate with that kind of variation one would risk valves cracking and seat recession on #2, and carbon fouling on #6. They were on different branches of the manifold with one branch averaging 14.4 and the other 12.8. The richer mixture was on the branch feeding #1,2 7 and 8, as would be expected trying to compensate for fuel dropping out on the longer travel length.
Jim
John, I suspect you have some airplane experience since measuring and controlling induction temp is commonly done, particularly for supercharged aircraft engines. I don’t think it would work too well based on the outside surface temp of the intake manifold of a Pierce, since there is so much thermal mass in the cast iron manifold (wouldn’t respond quick enough to changing AF ratio) and its temperature is going to be highly influenced by the heat conduction from the block and the heat from the exhaust manifold. I think you would need a probe in the air flow itself downstream of the carb, and even then it probably wouldn’t tell you too much.
A big problem for long engines such as straight 8’s is the uneven distribution of the mixture from cylinder to cylinder. The fuel is still liquid mist when atomized at the carburetor and being heavier than air the centrifugal and gravitational forces on the drops as they fly around corners and along the length of the manifold effects the AF ratio at each cylinder. The heating of the intake manifold by the exhaust manifold and block help to vaporize the fuel along the way, but a huge challenge for these engines was trying to minimize the variation in AF ratio cylinder to cylinder.
Measuring the exhaust chemistry downstream of the exhaust manifold would only give an average of all cylinders, and one cylinder is probably running leaner than the others. As noted above, running leaner than stoichiometric is the most fuel efficient, but increases probability of lean misfire, maximizes exhaust temp stressing the valves and also provides the excess oxygen that promotes valve seat recession. Because of the cylinder to cylinder fuel distribution problem these engines were set up to run richer than stoichiometric to avoid lean misfire for the leanest cylinder at basic highway cruise power. Maximum power occurs richer than stoichiometric, and typically these engines were set up to run significantly richer than max power at wide open throttle to reduce knock and provide internal cooling. It also produces a lot of carbon from incomplete combustion that fouls the engine and was part of the reason for rapid wear leading to replacing piston rings and removing the head to “decarbonize” at ~15000 mile intervals.
The peak temperature one would expect in the exhaust manifold is not at wide open throttle but probably closer to the highway cruise position that coincides with the throttle position just before the carburetor “economizer” or “booster” valve starts to open up, dramatically richening the mixture for maximum power by dumping excess fuel to cool and prevent knock. Years ago I measured the AF ratio on my ’36 Packard EE-23 with a machine that you could put in the car and monitor while driving. I was a bit shocked to find the “booster” valve opened up at about 60 mph on a level road, and the slightest increase in throttle to go up a grade would peg the AF ratio to less than eight, the same territory one would expect of an aircraft engine at maximum takeoff power. I adjusted the “booster” to open a little later. Even so, I spend so much time at wide open throttle driving up hills at high altitude that the rich mixture always leaves carbon soot on the back of the car. I only worry about valve and exhaust manifold temps cruising down I-5, not climbing hills at wide open throttle.
Bottom line is I don’t think there is a proper AF ratio for these cars regardless of instrumentation beyond a bit of trial and error to keep them a little richer than the lean misfire limit.
I am reminded of my father who flew P-38’s in WWII on long missions where minimizing fuel burn to make it home was an obvious concern. They would slow the RPM way down, go to maximum cruise manifold pressure (throttle), and lean the mixture down to barely above the point of detonation (knock).
Jim
Sir William: Yes, the Jag is a ’68 series “1 12” which means it has some Series 1 and some series 2 bits, makes it challenging sometimes ordering parts.
The picture was taken last year and the frame was about to be rolled in to re-mate the body to it. I just finished main engine assembly and will be working the transmission/free wheel/power brake assembly next in hopes of engine start in a few months.
Jim
Yup.
I am not sure how the factory adjusted them, but by posting how I have done it maybe someone who does know will chime in.
It is a bit of an iterative process because how the body sits on the frame effects the door alignment and so it ends up being a combination of bending the hinges and adjusting the body pads. First I assume the door should have a consistent gap with the body along the hinge side (fwd edge of a front hinge door, aft edge of a suicide door). The hinges can be bent slightly in a press to adjust this gap – a bit scary but I haven’t had one break yet. When those gaps are good the alignment of the latches and wedges is done by shimming the body pads to basically bend the whole body. My ’35 Club sedan has more shims in the middle and a lot of load on the front bolts at the firewall forcing a bend in the body that pulls the door latches/alignment wedges up at the center pillar.
I don’t know if this is how the factory did it. If not I am hoping someone will chime in that has the original, better method!
Jim
