Re: 1929 626/633 Classic Car Rally Prep Recommendations

Posted by DavidM On 2019/9/9 17:32:36

"What are known fault areas in these Packards that need attention before long distance rallies? Period modifications? Recommended modifications? The car would have to be built not for power, but for maximum reliability."
As no one has chimed in on this I will give my opinion.
I have restored two 1929 633's and have had long term ownership and driving in one of those, a Roadster. Used as they were intended they are great cars. I have no experience with anything like the Peking to Paris and assume it requires sustained high speeds and handling on some rough roads .
In my opinion they are entirely unsuited to such conditions and I would say the same about at least most similar makes of cars of the era. You do not state what speeds and distances would be required The standard Packards are good for maybe 50 mph max, they will go faster for very short bursts but at the risk of serious engine damage
They are very robust cars, that is not an issue, for their intended use.
Modifications : These are many issues that would need attention.
The engines are slow revving and they are geared to run in top gear down to walking pace, not high speed. My Roadster which has the are the highest drive ratio of about 4.3 : 1 will cruise at up to 50 mph but at that speed the engine is working very hard, 45 mph is better. Also these cars have babbit bearings which are apparently less robust at high sustained speeds than modern slipper bearings. Fuel consumption with hard use would be huge, sustained cruising at 45-50 mph requires about 12-13 mpg. With hard driving that fuel consumption could double or worse so with a 20 gallon fuel tank the range could be around 80 miles.
So what to do about those issues, high ratio drive &/or overdrive. More gears would be better, 4 or 5 speeds.
Large auxiliary fuel tank
Low revving engine, replace it with a much later engine, now it's a hot rod.
The suspension is good on good roads but these cars have massive unspring weight and hitting a bump on a tight corner throws them off line. Try lifting a complete back axle assembly it's a two man job and they will be straining. Maybe better shock absorbers would help that does not fix the fundamental problem. Independent back and front end suspension would be the ultimate solution.
The brakes are fine for sedate use but will fade easily with sustained use. I always change down a gear on long steep descents and reduce speed accordingly. Hydraulic disc brakes would help but keep in mind these are very heavy cars.
The steering has many turns lock to lock, fine for the intended use of the car but not good for any sort of competitive driving.
Lights are just OK at low speed for short distances, the generator will stuggle to keep that battery charged for any length of time when using the lights so 12 V modern alternator and driving lights will be essential if night driving is required.
I don't know how well the 90 year old wood framed body would hold up under rough conditions , not well I suspect.
There may be other issues I have not thought about but unless I am completely misunderstanding the type of long distance rallies proposed, the Packard is a very poor choice and the modifications required would destroy the original car.
Maybe I am being a "killjoy" what do other think?