I've got too much time on my hands - broke my ankle a couple weeks ago and am pretty much restricted from working in the shop for a couple of months (crutches, dirt floor and piles of crap do not mix well). Taking advantage of the time on my ass in the recliner I am thinking about how to go forward with projects, one of which is a '40 Ford Tudor. I have been collecting parts for it for 35 years and plan to start work on it some time next year. I'd like to stay "traditional" with a '40 truck engine I already have and maintain the original drivetrain/suspension/steering/brakes, but the nagging thing in my mind is that I'd love to put a SBF in it. One of the bugaboos of such a swap is the exhaust system, specifically clearing the stock steering gearbox. I am aware of what most people do - block-hugging tube headers, for instance - but I want to approach this question from another angle - literally. I like the challenge of keeping the OEM/factory look, including the exhaust, plus I'm not a big fan of the tube header thing. It occurred to me that the original flathead exhaust manifold (albeit set up for single exhaust) on the driver's side drops the exhaust pipe toward the front of the block versus out the center-rear like on a typical SBF. I'm not aware of a cast iron exhaust manifold for the SBF that has a true center or forward outlet, hence my stupid question #1: was one ever made, and if not, would there be a good reason to engineer one? And if it could be done, stupid question #2 pops up: what would be the preferred way to route the exhaust pipe for a dual system around the mess on the driver's side that includes the steering gearbox, master cylinder and clutch/gearshift linkage? In order to answer this, I assume what was done "back in the day" for flathead dual exhaust conversions would be the thing to study. Can anyone provide info on how a "traditional" dual exhaust system was set up on a 35-40 to avoid the above-mentioned obstacles? Again, these are questions that a housebound, bored-out-of-his-gourd has been pondering. Surely someone else out there has wondered the same thing?
Since you want a factory look, why not change the position and angle of the stock manifold exhaust outlet to clear the obstacles and provide the clearance you need. Used this approach to put a 455 in a 1965 Pontiac Bonneville years ago and it worked well.
The big issue, hence the question, is are there already stock manifolds out there that would do this? I haven't found any, and as such I suspect that if there was one somebody would have called attention to it in the past. I'm not a welding wiz (hell, I've got a MIG sitting in the garage that I haven't used yet because I have no way to get a bottle of gas home for it, and a small gas setup I've yet to put the striker to), and have seen what others on the HAMB have done with cast iron, pattern-making, etc. It's that kind of creativity and home-grown engineering that interests me with the question: I've been an architect by profession for over 25 years and playing with old cars since the mid-70s but I've been out of work for a year to the day-not a great career choice apparently right now since apparently firms value 30-somethings with all the 3-D modeling CAD knowledge at a bargain price with no construction experience (I actually had an architect tell me I was "overqualified" - WTF? I hope the building you put your stamp on doesn't fall down and kill someone). It would be good to see some examples of what others have done, and I plan on spending my convalescing time to learn more about pattern-making and casting. It's somewhat of a mental exercise right now, but curiosity and the desire to prove something can be done kind of drive me as well.
I seem to recall a HAMB post that showed a collection of SBF exhaust manifolds, past-to-present. Inasmuch as they (manifolds) are interchangeable right and left, I suspect there was a 221 or 260 right hand exhaust manifold that had a rear flange that pointed downward, useable if applied to the drivers side of your '39, as the flange would be at the front, left side... If this is the case, the manifold (s) would have to have ports enlarged at the head flanges, obviously... I believe there was a Jeep application (SBF) so a call to some jeep dismantlers (wreckers) might be in order. Otherwise, some nickel rod and an arc welder are in order. BTW, you CAN get that bottle of inert gas. A customer of mine bought a bottle of Argon, called his local taxicab company to go pick it up for him! Taxi came to his house, driver carried the bottle up to his door. Total 'tariff' was $13.00! (Idea was so 'handy' that I used the taxi company (Campbell, CA.) to pick up parts at my local suppliers when I was busy at my shop...just added the delivery charge to the bill. Real time saver...) P.S.: About your excess in years, and limits in CAD: I share your frustrations, as I was a Senior Master tech with BMW of N. America, now retired. The young blood coming in without Factory training merely passed the standard ASE test. (a joke) Many misnomers occurred, (three Motronic Control units replaced on a car without leaving the shop, at $1,800 each!) Finally, I was asked to find the problem...Aftermarket phone installed at an Auto Stereo firm had a #6 metal screw bored & threaded thru a 50 MM wire ribbon...No warranty, (after m'kt phone) customer was charged 22 hours @ $95 per. It took me less than an hour to find, but dash, carpets, and a myriad of components had to come out....All this on a top of the line vehicle with 18 miles on it! Customer didn't want to spend the extra $1200 for the BMW factory phone? In an $85K Coupe???
I think Atwater Mike covered it : possibly use early Mustang Exhauxt maniflods swapped L for R & R for L(keeps the installation looking symmetrical, LOL ) then a couple of sections of exhaust pipe 'U' bends for each side to run under the steering & etc, then finish however you want( single/ dual/etc.) The early cast iron SBF Ex. manifolds exited straight back, so these would exit straight forward ; there were also the "shorty" tubing units to replace those & directly bolt in, so those might be worth looking at as well, as they'd have the same 'exit' position as the 'cast' units.( & No, they're NOT the 'block-huggers' you mentioned !)
^^^^^I agree--I run the blockhugger headers and they are OK but I admit I didn't look very hard for stock issue ones. Go with the Ford in a Ford---you won't be sorry. Very reliable.
Although I have a Chevy engine in my avatar coupe, I did what you have in mind. I modified a 2 1/2" center dump manifold to angle forward to clear the Chevelle steering box. Any competent welder can do this. I ran a 2 1/2" pipe around the front, tied it into the pipe coming from the passenger side, blended them into a 3" exhaust pipe that went back to a muffler that has a 3" inlet and two 2" outlets for the dual exhaust coming out of the back. Looks good, works good and certainly doesn't add to the clutter caused by steering box, clutch linkage, master cylinder, etc.
Looking at some dual exhaust installation photos on the web tonight made me realize that by keeping the exhaust pipes close to the inside of the perimeter frame rails I could get past the master cylinder, clutch and transmission linkage. Getting past the steering gear box and linkage I'm not sure about as I didn't find a good photo of this area.
I believe there is an early Falcon exhaust manifold for the left side that is more of a center dump or more of a forward angle to the dump. If you google an image for 1963 Falcon exhaust manifold, you'll find it. They show up on ebay but I haven't paid any attention to how much they go for. And I have no idea if they would provide what you are looking for.. Ok, I did some more looking and found the Ford casting number of the exhaust manifold I'm talking about. It looks like C3DE-9431-A and is listed to fit 1963-65 Falcons and Mercury Comets with a 260 or 289.
K-289 Stock 289/302 351 W 70-71 70s Maverick Grenada 70s truck Falcon Sprint/Ranchero You should be able to find a route for those pipes. It might take a patient and skillful exhaust man. You can always cheat a little and tweak engine fit at the mounts to give just a little more clearance on the divers side.
Thanks all. Will need to keep an eye open for the C3DE 9431-A's at future swap meets. Since I can at least do some CAD drafting while waiting for the leg to heal and to take my mind off the never-ending job search, I need draw up a frame, engine and trans in plan and lay out where the engine/trans would go. So now my mission is to get the dimensions needed to figure all this out. Find a copy of Wescott's frame drawing, dimensions for the SBF including motor mount location and dimensions for some popular transmissions (C4, AOD, etc.), 8- or 9-inch rear axle, etc...
I had a 302 in a 40 with a GM power steering box. Angle milled the manifold were it mounts to the head to clear the steering box.Worked great!
On an off topic car I used Foxbody Mustang stock manifolds and put the left on the right and the right on the left. Both dumped at the front after moving them side to side.
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