Hi Jim,
And, welcome!
I'll take a stab at some of your questions.
It sounds like you are set on one of the Michelotti-bodied cars (TR4/4A/5/250). Great! I'm 100% behind you, but I'm also quite biased after 25+ years TR4 ownership.
Googling on the Internet can help you find a lot of individual seller websites.
Although it largely looks the same, the TR4 (1961-65) is a somewhat different car from the later ones. It uses a ladder-type frame more similar to TR2/3, that is actually stiffer and more durable than the later cars' frames. It also rides a bit more harshly. And, some parts for TR4 can be a little harder to find (example, the late TR4/4A/5/250/6 steering rack is more easily found).
The TR4 uses the same basic 4-cylinder engine that was used from 1954 to 1967, TR2 through TR4A. The late TR4A version engine fitted with SU carbs is likely the most tweaked and best performing, in stock form. Slight improvments in cylinder head, manifolds, etc. added up to a little more power.
The chassis for the TR4A is a big change. It was designed to accomodate independent rear suspension, although an estimated 25% of TR4A were still fitted with live rear axle, instead. TR4A rear suspension is more difficult to tune, needs more care and maintenance, but is more comfortable riding and, done right, can give a little bit improved road-holding capability.
Earlier TR4 did not have wood dashes, but it was optional. TR4A all have wood. Overall, TR4 interior trim is a little less refined.
For safety reasons, there are some modifications that should be done on TR4A front suspension, as a matter of course. (Not needed on TR4, I am not sure if needed on 250). If driven hard, the rear hubs on the IRS models should be upgraded, possibly the axles/u-joints as well.
The TR250 is largely a TR4A with a 6-cylinder engine dropped in. There are a few other refinements. But, the engine is the main difference.
In England and Europe, a fuel injected version of the TR250, known as the TR5 was sold. This was not exported to the U.S., so they are rare here. It put out considerably more horsepower than the carb version in the U.S., roughly 145 compared to 105 bhp. The early Lucas P.I. (Petrol Injection) system is a little fussy and can be hard to find parts for.
The 6-cylinder engine is basically a very good one. The earlier 4-cylinder is probably a bit more durable. The interchangeable cylinder liners make the 4-cylinder easier to rebuild and modify, in many respects. There are a more used and new parts around for the 6-cylinder, since it continued to be used through TR6 production.
Each model has a slightly different soft top. The TR4 top can be removed to stow in the trunk, while the bare hoodsticks fold to be hidden under trim flaps in the cockpit. The TR4A and later use a less removeable top, more intended to be folded in the "rear seat" area and covered with a separate trim piece that snaps into place.
The key thing to watch for is rust. TRs tend to rust from the inside out. Common problem areas on the body are the inside top of the fenders, the rockers, the lower edge of the doors and the trunk lid. On the inner body, the sills, A-post and B-post bases are vulnerable. The driver's floor is often rust damaged in storage, by leaking brake/clutch master cylinders.
The frame has to be watched at the diagonal brace from the shock tower, at its base where it's welded to the main frame rail, because no drain hole was ever provided. Also look for ripples in the side of the main rails, that might indicate accident damage. Watch out for any TR without the crosstube support, from spring tower to spring tower in the engine compartment.
While I warn about rust, I don't really think that TRs are any more prone to it than many cars. The original Austin Mini and many other cars, American and imports, were probably worse. And, all the TR-series are body on frame construction, in many respects more easily repaired than uni-body cars like MGB. The TR4A and later frame is more prone to serious rust damage than the TR4 and earlier frame.
Driving these cars, all the usual engine checks apply. Watch for overheating. All the gearboxes should have synchromesh on all 4 forward gears. (If not, either the gearbox is worn or an earlier TR3 gearbox without 1st gear synchro is installed.) All models you are considering have rack & pinion steering that should be tight and precise.
If fitted, overdrive on TR4/4A/250/5 should work on 2nd, 3rd & 4th gears. 2nd gear OD should be used with some care, particularly with the earlier, harder shifting overdrives. It's easy to disable 2nd gear OD, while leaving it operational on 3rd & 4th, if wished.
You can find a lot of additional info about these cars all over the Internet. Still, I strongly recommend Bill Piggott's series of books on originality, along with Roger William's "Restoring Triumph..." series. If you want to do some performance tuning, Williams also has written a "How to Improve..." series.
The most generally desirable options on all these cars seem to be the original two piece hard top, A-type Overdrive, wire wheels (originally usually painted, but most fit chromed now) or Minilite alloys, wood-rimmed steering wheels and leather interior.
I don't follow costs closely. But, WAG/ballpark I'd say TR4/4A can be found for as little as a few hundred for a pitiful parts car to over $20,000 if in near concours condition. A daily driver in pretty good condition might sell for around $10,000-$15,000. A car that's largely complete but needs a lot of work, maybe is partially disassembled, an abandoned restoration project, might sell for $5000 or less.
TR250 are rarer cars and might sell for a bit more.
I'd expect a TR5 in the U.S. to bring the most of all.
An original hard top probably adds $1500-$2500 value; an overdrive is likely worth $1500-2500; wire wheels or alloys might add $500-$1000.
Oh, and one more thing. When originally sold, many of these cars were registered in the year sold, rather than the year built. So, for example, my car was registered in 1964 the year it was sold and licensed, although it was actually built in late 1962. The car's VIN/chassis and engine numbers can be important locating correct parts.
Have fun shopping! I'm sure you will get much more good advice from the folks here.
p.s. Back around 1977, when I bought my TR4, I was shopping for a sports car. I'd looked at several:
- two XK150s for $5000, some assembly required. Okay, actually a lot of assembly required!
- '63 XKE, in storage since 1964/65, but 1500 miles away. $2500
- '63ish 356, motor freshly rebuilt by a local Porsche tuning expert. It hit 120 mph with little effort! Needed paint (faded pale yellow) but the red leather interior was nice, if a bit flashy. $2500.
- My TR4, bright orange, but local and running well. $1800.
The poor, starving student in me won out. In those days, $700 was a lot of money! But I wish I could have bought them all!
Cheers!
Alan Myers
San Jose, Calif.
'62 TR4 CT17602L
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