Hi, I am asking if any of you have experience putting a modern 5 speed transmission behind a vintage Packard 120 strait eight engine? What works , what does not, what might be a cost effective alternative to say a brand new TKO unit? I have a 1937 Packard 120 straight eight engine and bell housing but no transmission. I've just gotten a suitable 132 inch long wheelbase chassis with 20 inch wire wheels I want to build a Special on using this engine .I appreciate your wisdom and advice.
The Packard transmission that came in those things stock was a highly prized hot rodder piece, very strong and a popular swap behind Ford flatheads of the day. If you can locate one, this is one instance where the original trans would be a really cool thing to have. That's probably why it went missing in the first place. But if those Packard transmissions could be made to fit behind the Ford engine fairly easily back in the day, it seems logical that any of the transmissions that fit behind the Ford could be made to fit behind the Packard. Not that I've actually tried it, but that seems like it should be true. Talk to the guys who run the Packard trans behind their Ford and see what it took to swap it, then reverse-engineer from there to figure out what you'd have to do to put the Ford trans behind the Packard. 132" Packard powered speedster on wire wheels sounds awesome, hope you can get it figured out.
Thank you for the encouragement. I do wish the transmission were with it but count myself lucky to have saved the engine . It was from a chassis that ran but had no body back of the dash and windshield if I recall. Some brothers decided to move to Alaska and made the back of it into a trailer. By the time I found out what they had done only the engine and bell housing was left. That was about 1980 or '81 in Walla Walla, WA.
If anybody knows these guys will. They can be a little tight assed about modifications so be sure and post in the "Modifications" discussion. If they think you are building a 'special' from parts it is much different from butchering a complete car. http://packardinfo.com/xoops/html/modules/newbb/
I'm not sure much difference there is between the back of the block on the 1937's as compared to the 49-54 straight 8's. I'm in the process of mounting a T5 behind my 1953 327 straight 8. I'm using a mid 80's S-10 T5 that has the mechanical speedo and a one piece aluminum Chevy bell housing (Its what I had). With this set-up the input shaft on the trans is 1" too long for the bell housing. Which is perfect as it gives me lots of room to build and adapter between the engine and bell housing. My plan was to use 1/2" plate (again, its what I have so the price is right), lay out the hole pattern for the Packard and GM and all the alignment dowels and starter holes. Drill and tap holes as necessary, weld both plate together and call it good. So far I've laid the holes out on both plate, I tacked the two 1/2" thick plates together and drilled the Packard and GM alignment dowel holes. While the plates were still joined I also drilled the 3 1/4" hole for the starter nose cone and drilled and tapped the mounting holes for the starter. I separated the plates and drilled the Packard mounting holes and clearance for the crank. I then bolted the Packard plate to the engine. For the other 1/2" plate I've drilled and tapped holes to bolt the Chevy bell to. I started to cut out the center for crankshaft clearance but ran out of oxygen on my torches (I always seem to run a bottle dry on a Sunday afternoon). Hopefully tomorrow night I can set the 2 plates together on the engine and bolt the bell housing on. I will have to notch the bell housing to clear the nose of the Packard starter and slightly clearance the outer edge of the bell to clear the flywheel diameter. It looks like its going to work. I'd post some pics but I haven't downloaded them from my phone yet. Bobby
Success! I have a T5 mounted to my Packard 327 I still have to trim the 2 plates to size and weld them together. I'll need to notch the GM bell housing for the Packard starter nose cone. After that I can figure out what pressure plate and clutch disc to use
Just a quick follow up. I got it all drilled, tapped, welded, etc. I notched the bell housing to clear the Packard starter nose cone. I didn't realize I had the small GM bell. I managed to dig up the larger truck bell this past weekend and was able to tidy up the adapter plate. I still need to modify the dust shield, fab a cover the starter nose cone and either purchase or buy the adapter ring for the front of the trans. The T5 bell housings have the 4 11/16" opening and the larger GM truck bell uses the 5 1/8" opening. I know that Novak adapters sells the ring but I think I might be able to fab one up
Hi, am so glad to have found your post, i've been asking for direccion on how to adapt a 5 speed trans to my 47 Packard Clipper S8 engine. I don't think your 37 engine its any different than my 47, i would love to know came out when finished.
My project has kind of been on the back burner and I haven't made any more progress on the tranny adapter. I do, however have a rolling chassis (mostly) and hope to have this thing running sometime this year. Here is my build thread; https://www.jalopyjournal.com/forum/threads/straight-8-rpu-build-thread.1083302/
I matched the crankshaft centers of the Packard with the Chevy and orientated everything else from there; alignment dowels, mounting bolts, starter mount, etc. Lots and lots of measuring, re-measuring, measuring again, over and over and over... ...and then re-measuring. I made templates from both cardstock and sheet metal. For the Chevy side it was easy, as you can find engineered drawings with bolt hole measurements anywhere on the internet. For the Packard side what ended up working best was to use the Packard manual trans bellhousing and some card stock and a set of transfer punches to mark the holes. The starter mounting holes were tough as there isn't much room behind them and I had to cut down a transfer punch to make it work. Did I mention about the measuring and re-measuring? Take your time, double check everything and give it a go. Whats the worst that can happen? Bobby
maybe get bolt holes in and mounted just snug. then mount indicator from crank and rotate crank with indicator attached and tap around center of bell until it runs true then drill and ream dowels thru. make sure indicator is real rigid or it will sag vertically and give false reading. better if you could stand motor on end but i don't think that would be easy with that one.
he is confused. the 5 speed works perfectly behind model A banger motors, it would work even better with the Packard
@Jorge cardozo The fact that the Packard engine operates at a relatively low rpm/high torque is precisely why the 5 speed is advantageous over a 3 speed. Think of it this way.....a human on a bicycle typically has limited pumping capacity and strength. Early bicycles had fixed gearing. Depending on operating conditions, it was easy to pedal, hard to pedal or too easy to pedal to efficiently use the rider’s capacity. Enter the multi-speed bike, first 3 speeds, then 10 speeds. Now the rider could pick a gear that allowed his/her capacity to be fully utilized regardless of terrain variations. Same thing applies to diesel powered heavy trucks. The diesels have narrow rpm/power band and the 10 spd, 13 speed etc. transmissions allow the engine to operate in that range regardless of load or road conditions. Your 5 speed trans will offer similar benefits to your Packard powered car.
Go back to you mechanic and ask for his "Mechanics License" and remove it from the premises. He clearly does not deserve it. Under his logic, a large, slow speed engine (like say something that is found in semi truck) would only need one or two gears. Not the 10 to 18 that are typically found in big rigs....
no need to bust the mechanics balls, he may be really good at diagnosing, front ends or electrical issues. he is not a car designer/builder. there are all types of mechanics, just like doctors...............would you ask your proctologist about your teeth?
Gosh, I'm an old mechanic, and I didn't even know the 5 speed guys were regularly spinning their engines 6,000 to 8,000 R.P.M.! My wife's O.T. BMW has a 5 speed, don't think it usually spins at those revs...I'll ask her.
If you are interested in an overdrive automatic, try this Speed Gems - Transmission Adapters They make a complete adapter kit, including starter to put a 700R4 behind the Packard 8. Search "Packard".
Just a shot in the dark here - did you ever have any involvement with driving a Beach sportsracer in the '70s...? John Rankin jlrankinco@comcast.net
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