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1932 Studebaker Indy car build


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All good suggestions! Dwight's cross member image is interesting. I could imagine using 3/8"or 1/2" steel plate and having my local metal shop laser cut it and bend it to shape in one of their presses, then weld in the square or rectangular tube section and the gussets. But, it's hard to get stiffness out of a thin, flat plate. I've never seen what the 1937 Studebaker sedan cross members look like, so I can't guess at width, thickness, shape, etc. I've asked a friend to send me some photos. As in the design Dwight posted, I need to come straight out from the frame rails (0.164" thick mild steel) at least 2" to clear the lower flanges, then drop down quickly to get past the generator in front and the bell housing/clutch in the back.

When I did a simple analysis on the deflection and stress of the mounts, I had to assume that the mounts were simple, straight beams and ignored the vertical sections. I assumed the ends were not pinned [though they are bolted firmly to the side rails] and all the load is at the center of the beam. This gives simple calculations and some idea of what's going on. The stress and deflections were low enough that I'm not too concerned that the real cross members are much more complicated. Assuming that the end plates of the cross members are attached to an unyielding frame rail reduces the deflections at the center by a factor of 2.5. See a JPG of the calculations below for a couple of versions of rectangular tube dimensions.

To do any real analysis requires having some Finite Element Analysis software to get stress and strain. My TurboCAD 3D design software is pretty good, but there is no FEA plug-in yet. Where I used to work, they have SolidWorks with COSMOS FEA, an excellent package. But, it costs $10,000-$15,000 per seat or more. I just did a search and found the site for LISA, some free FEA software for up to 1400 nodes and only $99 for a full license for many nodes. See www.lisafea.com. It doesn't look like I could import a design into LISA, would have to create the model within the software. This could be an interesting diversion for a few weeks. Has anyone used LISA? Here's a sample of LISA output for deflection and stress of a simple cantilever beam.

Estimating dynamic loads like bumps, chassis twisting, cornering, etc., is very difficult. I got a copy of "Race Car Vehicle Dynamics" by William and Douglas Milliken (father and son), published by the SAE, ISBN 1-56091-526-9. See http://books.sae.org/r-146/. It's like a college textbook of race car design, 900 pages for $99. I concluded that dynamic loads of a few g's are common, but don't expect to see 10g and higher loads - the car would get launched into the air first.

Many years ago, I knew an old-time chief engineer who was responsible for the design of large high-vacuum chambers and complex mechanical systems. Back then, 3D CAD and FEA weren't available to anyone but places like Boeing and NASA, but he coped well. His favorite quote: "Steel is cheap, son. If in doubt, use more steel!" It's still good advice. Sometimes, it's just cheaper and faster to go put something together and see if it works, then modify as required. At this point, I'm really interested to see how much the chassis will go down on the springs when I put the engine and transmission in place.

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You're a way ahead of me with the computer design diagnostics. I tried to use autocad once and never got beyond making a straight line. I like the crossmember that Dwight posted, but I would also like to add more webbing to the outside wings. I was thinking about the later (late 40's early 50's) Chrysler motor mounts that were advertised as "floating power". Basically they mounted the engine with high connecting points to eliminate a lot of the vibration and wobble associated with inline motors. As mentioned above, the isolating rubber strip was quite narrow compared to modern motor mounts. Notice that this one is also built off center to resist the torque loads. Have to say it would be prettier if it was just stronger and not lop-sided. Hmmm.....looking at it again, the design may have had more to do with clearing the generator and crank pulley than torque loads.

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Edited by whtbaron (see edit history)
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  • 1 month later...

I have been trying to figure out some details of the engine mounting and exhaust routing. I got a drawing made for the 8-into-1 exhaust manifold using eight 90-degree bends in 1.5" dia. x .035 wall 304 stainless, a 1.5"x3.5"x28" long x.035" wall megaphone, and a 3/8" thick stainless flange. I just got a quote from one shop for more than $5000 to form the parts, machine the flange, polish the pieces, and weld it together - but final details could bring it even higher. I was blown away! I was thinking more like $500-$1000 so that I didn't have to cut, fit, and weld the pieces. I don't own a TIG welder for stainless, but at those prices I could afford to buy a very good TIG welder and spend some time learning how to use it. Is my reaction to the prices out of line?

By the way, I have a nice 3D PDF file (3 MB) of the engine assembly if you have Adobe Reader and want to see the engine details:

http://www.studegarage.com/images/indy/engine%20block%204-3D.pdf

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Have you got insulators between the carbs and exhaust manifold mounting plate you bolt them to?

What about if you made the manifolds of steel? I would imagine a not-small proportion of that price for stainless will be for polishing. It is also harder to work with than steel.

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$5000 does seem rather pricy for a basic 8 to 1 manifold, even with the tapered bit and being stainless. I was quoted $800 NZD for bending up the headers for my flathead 6 dodge motor and an extra $150 for lazer cutting the plate( the place I'm getting the stuff done dosn't weld them up) I'm only getting mine done in mild steel though.

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Gary,

This is beyond my level of expertise, but I would think you could purchase the parts (SS or mild steel) from a manufacturer like this (http://www.coneeng.com/pdf/cone%20list%20PDF.pdf) and have someone fit and weld the pieces for you. I would think semi-custom would be alot cheaper than full custom.

Dwight

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Yes, I thought it would have been cheaper based on the catalog prices of the company that quoted me for the fabrication. The megaphone was about $60, the eight bends were about $36 each. The raw stainless for the flange is less than $50, so about $400 for material - in stainless steel. They even offer their wholesale customers a 20% discount, so their real costs are quite a bit lower, say $200-$300 for everything. That leaves $4800 for their labor and profit to cut, polish, and weld. It should be about half that in mild steel. I can get the flange machined locally. If I use mild steel for everything, I can MIG it together myself. The biggest challenge is figuring out the shape of the hole where the bend in the 1.5" dia. tube intersects with the megaphone cone. My math skills are pretty good but that intersection is a mind blower. It's sort of worth trying to do it myself, if only to have a good model to give to someone else to do it better.

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The pdf drawing is pretty neat to play with! I haven't seen that before with pdf files. Xclnt.

Maybe I see the problem with your engine mount. It looks like you are supporting it below the vibration damper. If you support it on wings, like my Dodge or the Chrysler picture above, you remove this constraint. You also mention the racing engines had "wings" on them for the front mount. You already have a plate under the timing cover, why not turn it into "wings" to mount the engine?

If you look at plate 01-3 in the '34-'46 Chassis Parts Catalog, you will see the President and Commander Eight picture. The engine mount is pretty much behind the vibration damper. It is also made from an extension of the timing cover. Item 0101-1 (Plate) on Plate 01-8 may be able to be modified to make an engine mount for you, rather like the Studebaker "wings" you mention and the Dodge system. If you do it this way, you won't need to engineer your way out of a self-imposed problem = your proposed deep-drop cross member.

I can't recall what are you proposing for the radiator cross member. Rather than a deep-drop cross member, how about more rows in the radiator?

I now think your design will be governed by strains and fatigue, not stresses. I postulate the fatigue life is enhanced by keeping strains below a certain level. (I have been through the stress vs strain design route myself and got it wrong. Deflections were so great the things didn't work without stiffening to control strains.)

Another thing I notice in the chassis drawings in Section 15 of the chassis parts catalog is that the early chassis, Commander, Dictator and President, had the engine and radiator support cross member flared at the mounting ends, maybe to spread the stresses into a greater area of chassis.

Did the racing engines use a full length deep sump or a short sump to control oil surging away from the pump pick-up?

Edited by Spinneyhill (see edit history)
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The biggest challenge is figuring out the shape of the hole where the bend in the 1.5" dia. tube intersects with the megaphone cone. My math skills are pretty good but that intersection is a mind blower.

Surely your CAD program can draw a template for you?

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You can buy tube cutters & notchers that use hole saw blades to cut any angle and/or hole that you need. You set the tool up in a drill press to the right angle and right size hole saw and it cuts the right shape for the pipe intersection. Below is one supplier but there are quite a few out there.

http://www.medfordtools.com/tube_notching_101.html

http://www.harborfreight.com/pipe-tubing-notcher-42324.html

By the way, I also think the price you got is way too dear. Maybe try a local Hot Rod builder shop. If you do build them yourself out of stainless the cutting speed of the tube cutter must be very slow and you must use plenty of cutting oil/paste like Trefolex or one of those or it will burn the teeth off the blade.

Edited by DavidAU (see edit history)
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Yes, it looks like the tubing notcher is the way to go, and the Harbor Freight price is right! I won't need to worry about the shape of the holes, the notcher will make it just right. I can buy the eight bends and megaphone cone in stainless steel, plus a blank for the flange, at less than $400; the same in mild steel is $200-$250. I think I'll buy the mild steel parts, then I can weld it together with my MIG welder. This is one case where a TIG would sure make a better looking weld when it counts. It will be a little tricky to clamp the cone, but not too bad.

Spinneyhill, I did try to buy the front and rear engine mount plates as used on the 1929-32 engines, but couldn't locate a set at a reasonable price, e.g. buy an entire engine and ship it across the country. I'm having to make some compromises to keep the project moving. I don't want to run out of life or money before getting to drive the car. I agree that fatigue from flexing will be a issue in avoiding weld cracks or failure of chassis parts. I'm trying to stay below 1/3 of yield stress for static loads to allow for flex stresses that will still stay below yield. Look at the photos back in my post #76 in this thread to see the 1-1/4" dia x 1/8" wall tube I'm using for the radiator support. There are two bosses welded to the tube to hold the vertical brackets for the radiator shell and radiator. As with all of the rest of the crossmembers, the tube is welded to 1/4" thick end plates with three bolts per side for attaching to the frame rails. The radiator will be 4-core, 3-1/2" thick (more than stock), and it will use an electric puller fan since there is not enough clearance under the hood to spin one with the fan belt. The original cars had no fans. I may need to keep the fan mount and pulley just to have a way to adjust fan belt tension. I think the engine oil sump used on the engines under development in 1934 was the standard one. Of course, Studebaker always painted the insides of the block with red Glyptal, even on sedans and trucks, to eliminate casting porosity and improve oil shedding.

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Spinneyhill, I did try to buy the front and rear engine mount plates as used on the 1929-32 engines, but couldn't locate a set at a reasonable price, e.g. buy an entire engine and ship it across the country.

Can you get the drawings from the museum (or measure up a pair) and make some?

I see here http://1.bp.blogspot.com/_UlK0t3FwMY0/TNTVHEhaINI/AAAAAAAABJo/VkVGIKTartA/s1600/commander_8_engine.jpg the types of mounts you probably mean. The Dodge system is very similar, except the Dodge has a cast mounting "plate" on the rear. If you start with flat plate is should be easy enough to bend up a mounting to suit

Edited by Spinneyhill (see edit history)
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  • 2 weeks later...

I'm a stubborn kind of guy, but having actually welded the rectangular tube mounts together, it turns out they won't fit and can't be made to work. Too much interference with the spring shackles. And, yes, they were UGLY! Anyone want some 1.5"x3" cross members strong enough for an M1 tank engine?

So, back to the (electronic) drawing board to model up some flat plates like they were going to use in 1934. I have the photos of the development engines then and the manufacturing drawings for the engine block I am using, so I have most - but not all - of the critical dimension information. I may be close enough to let the shop laser cut and bend the plates, though. The "wings" have to be short enough to allow the engine to be lowered into the frame rails. I'll need some other small mounts to couple the frame rails to the engine plates, as they did back then. I'm going to have to pull the harmonic balancer and the front cam drive cover to look inside, a task I have been delaying for a long time. The front plate has to have holes to provide space for the cam drive gears and the front of the crankshaft, etc. The front plate will be flat, 0.164" thick if I stick to what's there now, 0.25" thick if there is room to move the cover forward and not hit the harmonic balancer and crank pulley. The back plate can be 0.150" (9 gauge) if I can't move the bell housing backwards, 3/16" (0.188") if I can slip it in. I don't want the block oscillating front to back. Anyway, here are drawings so far with some photos from 1934 of the original engine. My mounts are a little different because the factory was probably trying to adapt to the side mounts that were there for the old 337 cubic inch engines used is 1931-33. I may have my crankshaft centerline at just a little different height. Once I get all the drawings done and am sure it will all fit, it's off to the sheet metal shop again.

The original rear plate had small stiffeners riveted to the main plate. I don't have the right stuff for putting good heads on 1/4" shank steel rivets, so I'll use 5/16" bolts with red Loctite to hold them tight in spite of the vibrations. Anyone have experience with blue versus red Loctite? The red stuff seems to be "forever"; the blue can be broken loose with a strong wrench.

Oh, the big notch in the front plate is to leave room for the generator clamp band. The original cars didn't have generators or batteries, just a shaft running back to the side-mounted water pump. I can't see how they planned to adjust fan belt tension on those engines - and there was no fan!

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Edited by Gary_Ash (see edit history)
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That looks more like it. Pity about the "wasted" effort. I noticed on the Studebaker thread about an inherited 1930 FH President, the front engine mount (similar to this) had a top flange (bent backwards) for strength. No doubt the rear mount is similar.

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I saw the thread about the 1930 FH coupe. That would be a sweet ride, could be a nice "driver". I sure don't NEED another car.

The rear mounts on those big 337 cubic inch engines were mostly cast into the block. There was a bent U bracket with a stiffener plate that joined to the Indy car frame rails. Here are some photos of the green #37 car showing the rear mounts and some shots of the white #34 car when it was being restored for Brooks Stevens many years ago. Whatever front mount those engines had in sedans was replaced by a thick, flat plate for the Indy cars. Here is a shot I took of the front mount on #37 while lying on my back under the car. You can see the nice weldment that mates to the flat plate. I'll need to make something like this, too, as well as U-shaped ones for the rear. The Indy car engines were solidly mounted, no rubber. The early sedans with the 337 engine, like that 1930 FH, had little, if any, rubber.

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  • 6 months later...

Just catching up. I just had a thought - those flat plate mounts you show a couple of posts ago probably don't offer much control of longitudinal movement. How are you getting on with this challenging project?

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I got diverted by a couple of family responsibilities, some business travel to the west coast, putting up a 160 meter band Windom off-center fed dipole antenna for some ham radio stuff.  Now that summer is here, I'm back at the Studebaker projects, looking forward to the upcoming St. Louis Studebaker meet in August. 

 

Yes, Spinneyhill, the longitudinal rigidity needs to be addressed.  I looked carefully at the front mount that was used in the 1929-33 Commander and Dictator 8 engines.  That plate seems to be stamped from a 1/4" thick steel plate.  It is mostly flat but was folded at the edges to provide the front-back stiffness.  I think I can extend the edges of the plate and fold them in a brake, then weld them to form a kind of ring around the plate.  Still, the photos from 1934 show a flat plate in front, though it might be as thick as 3/8".  I can do that as long as the front cover can move forward that far and not contact the harmonic balancer. 

 

I've been staring at the shrinker/stretcher tools at Harbor Freight.  I need to buy one, and the foot-pedal operated ones on a stand are really the thing to have.  That and a few more pieces for the oxy-acetylene aluminum welding rig and I can start to fabricate some body pieces from the 0.050" thick, type 3003 aluminum sheet that I have. 

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Before you pull the trigger on cheapy Chinese stuff at Harbor Freight, check out Eastwood's selection. It will be more money, but I think you'll be happier with the quality in the end.

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Yes, you are probably right about the quality issues.  On the other hand, there is an HF store about 10 minutes away from my house and a Tractor Supply place within 15 minutes.  It's very easy to drop in and look/buy while I'm out running other errands.  Nothing like instant gratification!  I figure if I can get the primary task done with the HF stuff before it breaks then I'm doing OK.  I agree that any tool that needs to live through a number of tasks ought to be more durable and better quality.  But, remember that almost anything we buy now that is a metal part or tool probably comes from China anyway - a pity, but that's the reality.  I did buy a U.S.-made press brake kit from Swag Off Road for my HF 12-ton hydraulic press and found that it was pretty good and a fair price.   

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We don't have Harbor Freight up here, but a lot of the same quality merchandise ends up in our Princess Auto stores. There are some items that I have had good luck with. The hydraulic jacks that you mention (hydraulic cylinders in general) would be one of them, air powered die grinders would be another. You are correct in that a lot of items on our shelves now, even from name brand companies, is being made in China. Even companies like Victor and Snap-On are outsourcing, but that doesn't mean that the quality is the same as HF. It's unfortunate, but the quality is still generally better from a name brand company. If the bead roller does that job you will be money ahead, but if it doesn't you just lost the down payment on a much better tool. I'm still guilty of perusing those shelves too (got a great sale on automotive wiring next week) but I'm becoming much more selective on what I will buy there.

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I have/am enjoying your project. My mother's family had at one time 3-generations working in the Studie factory. One of her brothers, SR RAY MILLER had in his car museum several Studie's.

At this time I am building a 32" long model of the number 2 1925 Miller car. 1-5 scale, I have wonderful photo's of the car taken by Peter Harholtz, and have made contact with metal man Jerry Weeks here in Indy as he rebuilt the car a few years ago. I am going to visit his shop soon, as he had detailed photo's/drawings for me to review.

My piece will be of solid walnut, and copper, plus a 48" section of a board track. This is my ninth large scale model, my last was the GOOGLE RAYMOND LOWEY Locomotive, it recently won best of show in a juried art contest/show.

Really enjoying your build,

Dale in Indy

I might add, being a straight Buick fan, mine will have 8-exhuast header pipe on the left side.

Edited by smithbrother (see edit history)
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See John Snowberger's web site for models of that ilk.  http://www.johnsnowberger.com/

 

You would also enjoy his book about his father, Russ Snowberger, who drove many Studebaker-powered Indy cars in the 1920's and 1930's.  The book is called "Russ Snowberger" and is available from the Indy Speedway Museum shop.  It's a great "coffee table" book, many photos of Indy cars from the 1920's through 1960's.  Well worth the price.

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  • 6 months later...

I have a lot of stick time in the 34 car when Brooks was alive ....... Road raced it many many miles. In proper trim the car is FIERCE! And has no brakes. it was fun pitching the car to slow it.

 

About Gary's car......... The Brooks Steven car had original firewall and all the identity plaques ..... A Studebaker engineer made #34 into a street car. as I recall the conversion consisted of adding fenders. The car has the original engine, frame, Firewall. So what "body Parts"did Gary start with? At first he told me he had the car. Then I told him I'd driven the car at speed....... The he said Brook;s car was a re-body. Why would someone toss the original body and not the firewall?

 

For GOD sake please make sure it will stop!

 

Good luck with your project.

 

 

 

    

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All of the Studebaker Indy cars went through a lot over the years.  It's been 85 years since #37 was built and 84 years for the others.  They have been raced and crashed, modified and restored, but they continue to exist.  Car #34 in 1933 had one of the wind-tunnel designed bodies.  I'm not sure what the body was that was on the car when it got converted to a sports car, but it apparently was not the body used on that car in the 1933 race.  It could have been one of the other 1933 bodies because several of the cars reclaimed their 1932-style bodies or it could have been a body fabricated from scratch.  The chassis and radiator shell were found in Wisconsin about 1961 without any body.  The chassis was bought by Brooks Stevens who commissioned the Besasie Engineering shop to fabricate a copy of the 1933 body.  While this work was going on, the original 1933 body for #34 turned up in a garage in Chicago and was subsequently sold to a guy in California where it still lives without being attached to any chassis.

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The aluminum bodies are just skins.  The tail section is hollow and self supporting.  The forward section comes free of some underlying angle-iron framework to which the aluminum plate firewall is attached.  So, it's not a surprise that the firewall stayed with the #34 chassis.

 

While #34 may have retained for some time the cable-operated 12" brakes with stamped steel drums from the early '30s Dictators, it is now equipped with 12"x2" hydraulic brakes (Dexter trailer brakes)  and cast-iron drums as used on 1960s full-size Buicks.  The current engine is a larger-displacement Pierce-Arrow block, nearly identical to the 337 cu in Studebaker blocks.  The car goes fast and stops well.  I had a very nice ride in this car at something over 100 mph.  The car is currently owned and driven by August Grasis III. 

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I'll have PLENTY of stopping power with front brakes from a 1963 Buick Riviera:  12" x 2.25" with aluminum 90-fin drums.  I've also got the Riviera finned drums in back with 12"x2" shoes and backing plates from a '60s Buick sedan.  See my post #48 back a few pages for some photos.   

 

I started with nothing but a few photos, the Ray Kuns magazine article from 1935, and a lot of advice and free access to #37 for measurements from Bob Valpey.  I have acquired a wooden body buck used in the early 1980s to fabricate a new tail section for #37 and a pile of useful drawings and photos from people who restored these cars.  But, it's still slow going.  Satisfying to me, but still slow.   

 

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Thank you

 

You have provides the info I needed to fill in one more gap.

 

I am very happy that Mr Kuns owns the car now and has sorted the problems.

 

My interest in the cars really started with the story in "OLD CARS" They are wonderful things.

 

We have about 40 cars ..... I really don't count them. Most owned for many years. Take heart things go painfully slow and then one day you'll have "done" Seeing what you have done so far and so well I know the end result will be wonderful

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  • 3 months later...

The Indy car project became a neglected child due to a bunch of family obligations and house projects, but I'm happily back at work in the garage now.  My preliminary design for some cross members/engine mounts using the original front engine plate assembly on the 1937 Studebaker block turned out to be too cumbersome, ugly, and it didn't fit well.  I went back to the original 1934 Studebaker photos for the engines they were preparing for Indy and copied those plates.  Of course, there were about 20 holes in each plate that had to be precisely located, so I ordered up blueprints of the original engine block and plate drawings from the Studebaker National Museum - what a fantastic service!  Scaling from the old photos, I copied the plates pretty faithfully in my CAD system and designed short, stiff mounts to bolt to the frame rails.  The combination allows the engine to be easily removed and re-installed. 

 

My local metal fabrication shop laser cut the plates and mounts (3/16" thick) and bent them as needed.  The mounts are made like boxes, and I welded the seams for extra strength.  The real challenge was to locate the mounts on the frame rails in the exact front/back and up/down positions so that the engine would drop into place exactly level and all the bolt holes would line up.  I sweated bullets over this, but it did finally come together.  The next steps are fabrication of the exhaust manifold and mounting the steering box.  I bought a 17" steering wheel from Schroeder Steering with a squeeze-lock hub so that the wheel can be removed to get into the car.  The space for the driver and riding mechanic/passenger is really tight, as the body will only be about 36" wide.  The passenger actually sits about 5 inches farther back than the driver. 

 

The first picture below shows the cross members I made that I didn't use. 

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Here are the new plates and mounts:

engine mounts 1.jpg

 

The mounts bolted in the chassis:

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The new and old rear engine plates. 

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At last!  The engine bolted into the chassis and transmission in place.  The drive shaft will be very short.

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The Schroeder wheel and hub:

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Edited by Gary_Ash (see edit history)
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I got the hard work done on the exhaust manifold today.  I bought a bunch of 1.5" diameter x.049" wall mild steel mandrel-bent 45° and 90° elbows and a 1.5"x3.75"x28" long megaphone from SPDexhaust.com.  The flange was 3/8" thick steel, water-jet cut by my local metal shop.  I laid out the design for the assembly on my CAD system.  I placed the elbows where I wanted them in the CAD design, then "subtracted" the elbows from the megaphone to get the shape of the opening for the tube penetrations.  While a round tube intersecting a flat plate needs an elliptical hole, a 45° tube intersecting a cone tilted at a 10° angle needs a more egg-shaped hole - and each hole is a different size when there are 8 intersecting tubes. 

 

I was able to have the CAD system "unfold" the megaphone cone into a flat pattern so I could trace the hole shapes onto the steel megaphone.  My buddy at the local machine shop said he couldn't figure out how to cut the holes because he had no way to grab the megaphone and prevent it from flying out of the milling machine.  I took the parts home and tack welded the megaphone to a piece of 1.5"x3" rectangular steel tube [leftovers from my aborted attempt at engine cross members].  Since I have a small milling machine and the megaphone was now firmly attached to a sturdy object, I figured I might as well mill it myself.  I manually fed the table while eyeballing the cutter's approach to my traced lines, then finished the holes with a die grinder. 

 

Some scraps of 2x4 and 2x6 wood were used to make a fixture to align the cone and flange, with a shallow pocket to hold the big end of the megaphone.  I welded the 80° bend to the small end of the cone to set the overall alignment, then cut and trimmed the other elbows to fit.  I test fit each elbow individually and used the die grinder on the holes in the megaphone holes to gain enough wiggle to get alignment with the flange.  With one end in the flange and the other end poked into the megaphone, I scribed a line around the elbows at the penetration point, then trimmed in ends of the tube about 1/8" longer so that there wouldn't be too much sticking into the inside of the megaphone.  With a little difficulty, like juggling a dozen things at once, I managed to get each of the other seven tubes into the flange and into the megaphone holes.  A rubber mallet was useful to persuade the elbows into the right rotational alignment, as well as proper penetration of the flange and megaphone.   I quickly put a bunch of tack welds on each end of the elbows to hold everything in place.  I even tried the assembly on the engine block to be sure it cleared the chassis and firewall.  One of the photos shows the inside of the megaphone with just a little of each tube poking through.  Now I just have to spend a bunch of hours slowly MIG welding a few inches at a time, then letting things cool, to prevent stress buildup.  I'm pretty happy with the results.  This was the assembly that I had been quoted as much as $5000 to build.  The elbows and megaphone cost about $250 and the flange was about another $100.   

megaphone_in_mill.jpg

megaphone_assembly_dimensions.jpg

megaphone_hole_pattern.jpg

megaphone_tube_fit.jpg

megaphone_with_fitted tubes.jpg

megaphone_interior.jpg

megaphone_on_engine.jpg

Edited by Gary_Ash (see edit history)
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Looking good, I'm guessing you are enjoying the THOUGHT process.  I know when building my modified 41 Buick limited I really enjoyed the thought process.  

 

I just finished building a 1/5th scale of the 1925 Miller Indy car out of solid walnut and copper.  Piece took over 1100 hours, and is on display in a ADVENTURES IN WOOD show/contest as I write, not a kit, no drawings, no patterns, just from looking at pictures.  30" long.

 

I'm just starting on a 1/4th scale of the 1910 Buick bug, it will be my most detailed piece.

 

I love this thread, keep on keeping on, 

 

Dale in Indy 

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Yep, most folks wouldn't understand that the holes you cut in the header AREN'T perfect circles, they are, but only when looking at them at the proper angle.  I wonder if you considered cutting with a plasma cutter, I have after making a 1/4" plywood pattern, using worm clamps to hold in place, then cut most of the circle, then moved the clamps to finish.  Not having a milling machine, I often have to make do, hehe 

 

What coating will be on the finished headers?

 

Dale in Indy 

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In this case, it was chew out the basic shape with the end mill on the manual X-Y table without crossing over the tracing lines, then finish up with a die grinder to the edge of the traced lines.  It's very low tech, but fast enough.  In the end, I had to die grind a bit more to allow the elbows to maneuver a little out the calculated positions in order to get the tubes into the flange and the megaphone.  Allowing a gap of about 0.030" is OK for welding while giving a little motion freedom.  A plasma cutter is great, but it's another $700 item that I can't use often enough to justify, and a hand-held torch wouldn't be more accurate.

 

Yes, I do need to put some kind of treatment on the manifold.  I'd like to blacken it with some kind of rub-on material.  I'm OK with re-doing it every 6-12 months as I won't be driving the car every day.  I think a porcelain treatment would be overkill.  Any recommendations?

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You could FLAT FINISH IN POWDER COAT. 

 

A tool and die maker in the 60's taught me, scribe your line, but NEVER cut down the center of it, leave it showing so you can dress up to it.  As you have stated, I know you know this, hehe.

 

I don't use my plasma cutter much, did build a rolling water catch cart for it.

 

I like your holding jig for the header system, what works, works, huh.

 

Your build is one of those where it's best NOT to look at the entire process, but ONE STEP AT A TIME.  Had I thought of all I had to do in the 1100 hour model build, well, I might have given up.  I'm like a turtle, slow but steady, I also like to STARE, kind of like an owl, fast eyes see little.

 

Wishing you well,

 

Dale in Indy

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If ceramic coatings look too modern for you, you could consider powder coating as suggested, or cheaper yet would be the spray bombs of heat resistant paint. With the work you put into that and how nicely it came out, I would think powder coat would be a minimum. I like the motor mounts as well... the first attempt was good, but these look much better.

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  • 2 weeks later...

The steering box is proving to be a lot of work.  I actually have two 1929 Studebaker President steering boxes that I'm working with.  The first came with the remains of the chassis I bought some years ago, the second I found at a local NOS parts dealer, but they are the same boxes.  The first one had spent 30-50 years out in a field and had a lot of rust.  The second came out of a wrecked car, but hadn't lived in the rain for so long.  They are both Ross "cam-and-lever" boxes with one pin and a three-turn worm.  While the first box had more rust, the pin on the lever arm had much less wear.   The worm and shaft from the second box were better, as was the cover tube (1.75" o.d. x .039 wall).  After checking how much of the 1" diameter x .188" wall tube for the shaft I needed, I cut off the excess and ground a weld bevel on the end of the shaft.

 

I bought a 4-spoke sprint car-style wheel from Schroeder Steering in California with a pop-off splined hub.  The largest hub available had a 3/4" i.d., so I had to machine an adapter from a piece of 1" 1018 cold-rolled steel bar stock.  Surprisingly, the Harbor Freight 7"x10" lathe handled this with few problems.  I think it's because I bought some decent lathe bits with high-tech inserts that really peel off the steel chips.  The adapter slipped inside the steering shaft tube and also inside the Schroeder hub with only a few thousandths clearance.  As the coupling of the steering wheel to the shaft is critical in the safety realm, I was very careful in the weld preps and the welding.  I think I got it right.  In the end, I got the splined coupler welded to the adapter and the adapter welded to the shaft.  Now the Schroeder wheel slips onto the splined hub and locks in place with three spring-loaded balls.  The hub has a flange that needs to be squeezed to release the wheel from the splined hub.    The tight fit in the driver's seat necessitates the use of a removable steering wheel.

 

So, the worst of the cutting and welding is done on the box itself.  Now I need to weld up the mount to the chassis and machine the hanger for the column.  Because the splined hub is on the shaft, I'll have to make a split bushing from Nylon 6/6 with molybdenum disulfide blended in and secure it inside the column tube once the shaft is inserted in the tube.  The original bushing seemed to be a ring of linen phenolic with rubber molded on the outside, but it was stuck to the shaft and the column tube after 87 years.  I hope my new design works!  

 

steering_box_parts1.jpg

shaft_adapter.jpg

shaft_adapter_parts.jpg

shaft_with_wheel_spline.jpg

shaft_with_hub.jpg

shaft with wheel.jpg

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