Tech Q&A for March, 2025

/ Model A Tech, What's New / By

Q:  I’ve started to look at a couple vehicles and am OK to spend a bit to get something that I don’t have to work through. My question is are any of your Model A’s capable of driving coast to coast without problems? Can they be that reliable? Are those 50,000 mile tires on them or how long do tires go? Anyways those are my questions. You’ve probably covered them but I’ve only watched three of the Q and A’s and haven’t got those answers. Thanks for the great videos!
– Chase

A:  In 1976, my girlfriend and I got her 1930 coupe (completely stock) ready for a 5 week vacation journey.  We did all the usual prep things like lubricate the chassis and change the oil, checked the 5 tires, etc.  We then drove from San Francisco to LA and the on Route 66 east and finally to Nashville, where MAFCA held it’s National Convention.  After the meet, we continued east to Williamsburg, Virginia, then to Philadelphia, Chicago, Mt. Rushmore, Yellowstone and then back to SF.  Total of over 8000 miles in 5 weeks.

Problems: yes, we discovered the brakes weren’t in as good of shape as they could be. Also had problems with the points; had to adjust them a couple of times.  But other than that, no big problems.   We toured at 50mph most of the time, traveling 200-300 miles/day.   So YES, it’s very possible.   Go for it.
– Rick Black

A: Rick has the best answer (as usual!).  Yes, Model A’s, when maintained properly, are fully capable of cross-country travel.  In some way, even better because they are so simple, there is a lot less to go wrong.

Like Rick, I have had the best luck with the Goodyear tires.  Not sure why since both the Firestone and Goodyear repro tires are made by the same outfit from the same materials.  Luckily, they are available at just about any Les Schwab tire center, even though they usually have to order them, but if stuck far away from home with a blown tire and no spare, you can spend the night in a hotel and be back on the road the next day usually.
– Paul Shinn

Q:  I am about to re-assemble my 1929 Model A engine and would appreciate your thoughts on what are the best practices regarding assembly.

Background:I had the engine machined locally in Connecticut, and the Babbitt’s poured from Paul’s Rod and Bearing in Missouri. Engine was bored to 40 over. New Pistons & Rings. New Camshaft. New adjustable Lifters. Head and Block were resurfaced and Valve Seats ground.

Assembly Plan:  Wash Engine with soap and water-Verify Bearing tolerances-My understanding they should be  0.015 clearance on Main and Rod Caps-Assemble Engine using assembly lube on all moving parts (Cam, Valves, Bearing Surfaces).  Oil only on the Cylinder walls, no assembly lube- Set valve clearance to 0.012 for Intake and 0.013 for Exhaust- Torque Main Caps to 80 FP- Torque Rod Caps to 45 FP- Fill the Engine with break in oil. I plan on using DRIVEN 10w40 (BR40).

Break in: Here is where I need some help. What steps should I follow to ensure the Engine is properly broken in. In the past I have rebuilt 60’s era engines and always broke the valve/cam in  by running the engine at 2000 RPM for 30 minutes. Do I do that with this little guy?

Any guidance on this would be appreciated. Thanks,

– Bob

A: You have a solid plan there!!  0.015 clearance is not critical.  +/- 0.002 is OK.  Main caps at 80 ft/lbs. is a tad high but probably OK.  As for “break-in oil”, you need to go a little thinner than 10-40.  Unless you have a full pressure oil system, if you’re relying on the stock splash and drip, then a 10-30 is the thickest you want to go.

Now, to answer your direct question- For break in, keep it nice and easy at first, but keep an eye on the temp.  You don’t want to overheat the thing right off the bat and have a valve stick on you.  Also, re-torque the head (55 ft/lbs)  after the first few heat/cool cycles.  The head nuts will stop moving after a couple cycles and then you’re good.  Once the head is sealed well and head torque doesn’t move anymore, then you can start pushing it harder.  Climb a few hills and push it pretty good and the rings will seat nicely.  Don’t baby it, it can take it.
All the best!
– Paul Shinn
Q:  As the owner of 2 model A’s (one driver and one project) and multiple T’s and other cars etc. I end up towing from time to time.
I happened to catch this video and when he straps the A down he uses the narrow light duty straps.  I have broken and bent many of these over the years doing things and never trust them to hold my car in place when towing.  I use the wider higher strength straps made for heavier loads like cars.
Most of us live in areas filled with road issues (potholes, bumps, speed humps etc) and other not so careful drivers.  In an extreme situation the narrow straps will fail dumping out your precious cargo.
– Mike Silbert

A:  Thank you for your input, Mike.

Yep, I use medium duty ratchet straps.  Each of them is rated at 2,000 pounds.  A Model A weighs about 2,200 pounds.  Theoretically, one strap could almost lift the entire car.  Using 4 straps, there’s nearly a 4-1 safety margin.  Also, I take pretty short trips.  If I were trailering a Model A cross country, I would go buy some heavy duty straps and ratchets for sure.
Also, my custom built Model A trailer has 2-foot tall sides welded to the frame and a 4-foot tall tailgate that has 2 locks.  Not worried about the car coming off.  If there was an accident that caused the trailer to roll over, the car is hosed anyway.  To be fair, have you seen some of the other dumb stuff I do?
All the best,
– Paul Shinn