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SCguy
04-26-2006, 11:44 AM
I'm now in the market for a TR4 project. I've found a car along the CA coast (haven't seen it yet) that has been mostly restored (frame off) by a shop. The owner of the car has left the car and the shop which was doing the restoration will be getting a "lien title" and then selling.

I'm interested in the differences between a TR4 and a TR4a. For instance... Did any TR4s have the turn signals mounted on the fenders or was this just the TR4a. This TR4 has a Survey(?) top and solid axle. What else should I look for?

Geo Hahn
04-26-2006, 12:13 PM
Yes, only 4As had those wing-mounted turn signals. The big difference of course is that all 4s were solid axle whereas some 4As are IRS (plainly indicated on the boot and equally obvious whe viewing the the rear end).

Many things to look for... first and foremost rust but since you have a TR6 I'll assume you know how to examine the body, floors, etc.

There were some changes during the TR4 production run: early ones had SU carbs, breather tube on the block, and a TR3-style long-necked radiator (possibly with a crank hole).

The later TR4s had ZS carbs, breather tube on the valve cover, no-neck radiator with no crank hole.

Both had the roadster set-up, i.e. the top removes completely and the bare hoodsticks get stowed under the rear area upholstery -- the operation of the TR4A top is similar to your TR6.

I have a 'late' TR4 but IMO there are no compelling advantages or disadvantages in the various production changes that occured.

TR4nut
04-26-2006, 12:15 PM
Larry-

A really good reference to compare vehicles is on the VTR website - gives a history and description of each car. No side lights on the TR4, they are mounted on the front.

The TR4 only came in solid axle form, the 4a was both solid axle and IRS like your 6.

The surrey top is never wanted, is considered unsafe, so if you get the car you should ship the top to me and I will dispose of it for you. Okay I made that last line up, its probably one of the most desireable features on either a 4 or 4a and will likely command a price premium for the car. But I will take it off your hands if you don't want it!

Good luck,
Randy

MadRiver
04-26-2006, 12:56 PM
[ QUOTE ]
The surrey top is never wanted, is considered unsafe, so if you get the car you should ship the top to me and I will dispose of it for you.

[/ QUOTE ]

/ubbthreads/images/graemlins/lol.gif You're a bad, bad man!

I second your view on surrey tops. Simple answer -- go for it if you've found one. /ubbthreads/images/graemlins/thumbsup.gif

Rusticus
04-26-2006, 02:30 PM
Late TR4As got also SUs - HS6. Early TR4s were H6. A lot of early TR4s I've seen have painted white metal dashes. I think almost all TR4As have wood dashes. The chassis frames and suspensions are completely different between the two cars. Clutches are totally different. TR4A has a different cam, exhaust manifold, two different exhaust systems, even a different hand brake. TR4A is negative ground. TR4 is "positive earth."

Not much in common between the two, really.

Banjo
04-26-2006, 02:38 PM
Rusticus, Correct. as a matter of fact the metal dash wasen't even an option by the introduction of the 4A.
You had to have wood. TR4s have the tin plate that the 4 small gauges set in (similar to a tr3 setup). On the 4A they are set directly into the wood dash.

Alan_Myers
04-26-2006, 02:48 PM
Hi Larry,

Good luck acquiring that TR4!

I must admint I'm a bit biased toward TR4, perhaps because I've owned the same one for about 30 years.

The commission number of the car is your best source of information and you can get even more from the British Motor Heritage website (https://www.heritage-motor-centre.co.uk/archive/certificate.html), by purchasing a certificate with details about the original build of the car, if you wish. That will tell you what equipment was originally supplied and how the car was finished, and usually has engine number at least, if originality is a concern. But, Triumphs did not have matching numbers for engine/body/commission/etc., like some manufacturers did. Commission number will be CTxxxxxxL(O). This might be prefixed with STC/year on a title or registration. The "L" at the end indicates LH drive/US version. If there is an "O", too, that indicates the car left the factory with an overdrive installed.

Back in the days when it was sold, TR4 were not given a model year like they are today. They were registered the year they were sold. For example, my TR4 was built in 1962, but is registered a 1964.

There were a number of subtle changes - and a few not-so-subtle - to the TR4/4A over the production run from 1961 to 1966 ('67/68 if you include TR250/5 which have the same basic body/chassis, but the 6-cyl. engine same as TR6).

Some of the production changes might be considered improvements - or not - depending upon your tastes and what you are looking for in the car. One purely cosmetic example: Personally I like the TR4A grill better and have used one on my TR4 (but presently have the original re-installed and am thinking of leaving it for originality's sake).

Earlier TR4 had a rather utilitarian looking white-painted dash (which I really like), while a fancier wood dash was an option. Later TR4 and TR4A increasingly had wood-covered dashes. AFAIK, by the time of TR250/5, all were fitted with wood dashes. Interiors were mostly finished in vinyl, but some cars had leather-faced seats.

The interior of the TR4A became a little more refined in a number of small ways. Minor changes to the cylinder head and stock exhaust manifold slightly improved TR4A performance. To make it a little easier to use, the clutch was changed on TR4A, to a slightly smaller and now more widely available diapraghm style. This is generally reliable on TR4A, but became problematic when used in combination with some other changes on the later 6-cyl. cars. The TR4 clutch has heavier pedal pressure, and weighs a lot more overall, but is generally a "bullet-proof" setup!

TR4 have a "ladder frame" that's stiffer and stronger than the TR4A and later cars. TR4 frame was essentially inherited from TR3, but given a wider track, beefed up in a few areas, and adapted for rack & pinion steering, which was an added feature of TR4 and later TRs. The frame is also a little less prone to rust than the later cars, but still can be a problem (should have been taken care of by the shop you reference, I would hope). I think part of the reason a friend of mine discovered when he cut up some frames a few years ago. TR4 (and earlier) frame rails appeared to have been painted *inside* before assembly (tack welding that leaves most paint intact). Later frames appear not to have been painted inside, plus have more openings for water and exhaust to intrude, and might be made of slightly lighter steel.

TR4 have non-adjustable front suspension geometry, meaning both caster and camber are fixed (but there are ways to adjust both, if needed, just not very easily).

The later cars have shim-adjustable front suspension. However, this is a weak point and reinforcement of the mounts is always highly recommended. Late TR6 finally got a beefed up inner/lower suspension mount. So, the front suspension was improved in some respects, but was also weaker.

The new independent rear suspension (IRS) introduced with the TR4A gave a nicer ride, but is a lot more complex and has some weaknesses, too. In fact, an estimated 25% of TR4A were still produced with a solid axle, similar to TR4, at the request of U.S. dealers who were concerned the new setup would be "too un-sports-car-like" for buyers! Even the solid axle version of the TR4A use the same frame as the IRS versions, however, so don't enjoy the stronger/stiffer ladder frame of the TR4.

The solid axle TR4/TR4A is generally easier and cheaper to set up for racing, where Triumphs were having a lot of success both in the U.S. and in Europe. On the other hand, the IRS could be very competitive, in some ways better on the track than the solid axle. It just required more time and money to dial in properly.

The rack & pinion on later TR4, TR4A and all the way through TR6 is different from early TR4. Many owners of the later cars remove the rubber rack mounts and replace them with aluminum ones more similar to the early cars!

Changes to steering and suspension helped to reduce bump steer tendencies and were probably also to better accomodate emerging radial tire technology. But, the prime concerns probably came from the marketing dept. and a softer ride was the general trend, to best appeal to the huge U.S. market (about 90% of TR4/4A sales).

The IRS cars - TR4A and later - never saw factory European rallying like the earlier cars did, due to concerns about the flexier frame and weaker suspension. But, in the U.S., the IRS cars were raced with factory support, and saw a lot of success in many events, including the Sebring 12 Hour endurance race.

As already noted, SU H6 carbs (also ala TR3) gave way to Zenith Strombergs, but eventually returned to SU HS6 carbs, then back to ZS! They really are pretty equal in performance, the later SUs are probably easier to get parts for and SUs in general are a little easier to tune up at home.

You mentioned that the car you are looking at has a hard top, and I agree that an original one is a valuable addition, adding probably $2000 to the value of the car. There were aftermarket tops too, though, that don't add as much value. Some were fiberglass, both one and two-piece designs. One had an injection molded black plastic roof panel combined with a fiberglass window frame (sometimes called a "Sebring" top). Nearly all have Lexan or some other type of plastic windows. Original tops have a cast aluminum rear frame and the hard, roof panel is either aluminum (early version, first 500 made) or steel (later version). Original tops came with Triplex glass windows, but these were sometimes changed to plastic by racers to reduce car weight a little. Non-original two-piece hard tops add value, but probably only about half that of an original. One-piece aftermarket tops probably only add $200-400 value, and some styles actually detract from the car's appearance, IMHO.

The two-piece hard top is often now referred to as a "Surrey", but that's not the original terminology. Triumph simply referred to it as the "Hard Top", which included the rear window & frame, and the metal roof panel. These were fitted at the factory, or available through dealers as an accessory kit that included all the trim and hardware. To fit a kit, the cockpit mouldings were removed, different interior trim panels are used in the back, the "hoodsticks" are removed, and TR4 are fitted with special, longer stainless steel fender beading (later used on all TR4A) and longer rubber & fuzzy weather stripping/seals.

In Triumph catalogs, the "Surrey" was just the vinyl panel and it's small folding frame, that were a separately available accessory for the Hard Top. These were offered simply because the hard top roof panel is too large to stow anywhere in the car. The Surrey was useful for anyone who got caught in a rain shower after leaving the roof panel at home for a little open-air driving!

The TR4 two-piece hard top is often called the first "Targa top", and essentially was copied by Porsche for the 911 Targa five years later.

Another highly desirable optional accessory for TR4/4A is an A-type overdrive. To find out if the car you are considering has one, look for an overdrive switch on the RH side of the steering column. It will be a lever like the turn signal on the LH side. If the body is off the chassis or the gearbox cover is removed, or looking up from underneath, you can see the overdrive itself mounted on the rear of the gearbox. There is some additional wiring also. A good, working overdrive probably adds $2000 to the value of the car, and gives an effective 7-speed gearbox since it works on 2nd, 3rd and 4th gears. Some folks like the later J-type (TR6), which operates more gently, but personally I think the A-type is much, much stronger and appreciate it's rapid shifting capabilities. Some cars were shipped from the factory with overdrives fitted. Or, conversion kits were provided so that they could be added by dealers.

Let us know if you get the car.

/ubbthreads/images/graemlins/cheers.gif

Rusticus
04-26-2006, 07:39 PM
Quote:"In fact, an estimated 25% of TR4A were still produced with a solid axle, similar to TR4, at the request of U.S. dealers who were concerned the new setup would be "too un-sports-car-like" for buyers!"

Funny, no one ever said that about the IRS Jag XKE. Face it - they were cheap! :>)

Alan_Myers
04-26-2006, 08:44 PM
[ QUOTE ]
... even a different hand brake....

[/ QUOTE ]

Quite true! I forgot about that...

TR4 handbrake works. Tr4A's doesn't. /ubbthreads/images/graemlins/rolleyes.gif

[ QUOTE ]
Not much in common between the two, really.

[/ QUOTE ]

Yeah, there's a lot different. But there is still a lot of commonality and, where there are differences many are subtle. For example, floor pans are slightly different and only TR4A are still being produced, but are very easily modified for use on TR4. Door skins, too, which are very similar all the way through the TR6 actually.

We could keep this list going, and going, and going...!

/ubbthreads/images/graemlins/cheers.gif

Kurtis
04-26-2006, 10:12 PM
Larry,

Others have mentioned most of the differences. A couple of cosmetic differences that I didn't see mentions are the locations of the front bumper overriders and the front grille.

I really like the TR4 style top versus the later convertible top. It's much easier to keep the top looking nice since you can remove it completely from the car and store it in a safe place when not in use.

The TR4 also had an optional "occasional" back seat. This is really only suitable for small children and then only when the top is off. I carry my kids back there during low speed events such as parades or drives around the neighborhood.

4aKen
04-26-2006, 11:29 PM
I resemble that handbrake crack. I like all the changes that created my 66 TR4a irs, but I like the TR4 a lot. I think all of us running around in this Michelloti range of TR are real lucky. Rusticus and Alan, you guys are impressive.

Alan_Myers
04-27-2006, 03:30 AM
[ QUOTE ]
The TR4 also had an optional "occasional" back seat. This is really only suitable for small children...

[/ QUOTE ]

... and dogs. My old dog loved the "parcel shelf" of the TR4. He'd hang over the side with ears and tongue flying in the breeze. He thumped his head pretty hard on the roll bar more than a few times, going over bumps. But his elevator never went all the way to the top floors anyway, so no real harm was done.

The rear "parcel shelf" and fully removeable top *did* come in handy on more than one occasion... I recall picking a friend up from the Denver airport one evening.... She had so much luggage! After the trunk and trunk rack were crammed full, no choice but to remove the top and strap the rest to the roll bar. Unfortunately it was the middle of a cold, snowy winter night with a 30 mile drive ahead of us, up the freeway to Boulder. Thawing out was fun, though.

The 4A didn't have an occasional seat option? I wasn't aware of that. I suppose that's because the later style top takes up most of the space when stowed there.

/ubbthreads/images/graemlins/cheers.gif

Alan_Myers
04-27-2006, 03:47 AM
[ QUOTE ]
I resemble that handbrake crack.

[/ QUOTE ]

Sorry, um... let me try to put it in a more positive tone....

"The TR4A handbrake is at least as good as my Land Rover's!" /ubbthreads/images/graemlins/wink.gif

Seriously, I do like the TR4A's location of the lever better, on the driveshaft tunnel. The factory rally TR4's had their handbrakes relocated there (rally driver's use the handbrake to slide the car around corners.) There are ways to modify the TR4A and later handbrake to make it a lot more effective.


/ubbthreads/images/graemlins/cheers.gif

jsneddon
04-27-2006, 11:16 AM
Alan - you should just copy your first post verbatum and put it in the Knowlege base as a TR4 buyer's guide.

I'd also like to see it stuck in the Triumph Wiki https://www.vintagetriumphregister.org/mediawiki/index.php?title=Main_Page - if you don't want to take the time to do the work I'd gladly post the article for you with your permission and credit.

Alan_Myers
04-27-2006, 02:44 PM
[ QUOTE ]
Alan - you should just copy your first post verbatum and put it in the Knowlege base as a TR4 buyer's guide.

I'd also like to see it stuck in the Triumph Wiki https://www.vintagetriumphregister.org/mediawiki/index.php?title=Main_Page - if you don't want to take the time to do the work I'd gladly post the article for you with your permission and credit.

[/ QUOTE ]

Hi Jim,

I'm flattered! Sure, go ahead and copy it wherever you wish, but it might need some editing.

It's by no means complete, either. I keep thinking of things!

/ubbthreads/images/graemlins/cheers.gif

jsneddon
04-27-2006, 03:15 PM
Here you go Alan:

https://www.vintagetriumphregister.org/mediawiki/index.php?title=Notes_on_the_TR4_and_TR4A

I think you have to "accept the terms" to get in but you don't have to register.

The beauty of this is that if you _do_ register then anyone can add to existing articles, create new articles, etc. etc. etc. It isn't hard, it's just a text editor in your browser, you don't need to install any software, you don't need to submit it for approval, you just put it up and hit save. If you don't want to fiddle with formatting or anything just put it up raw and someone else can come along and clean it up for you.

The traffic is way too light to this and I encourage everyone to take a minute to check it out.

It really has the possibility to be a good repository of all those little snippets of information we all have stashed somewhere. I'd love to see a more LBC-wide version set up somewhere instead of just TR-related information and I think BCF would be a good jumping-off point for it provided someone had the time, server space, and bandwidth to set it up.

[edit] Oh. and THANKS Alan! you are a gentlemen's gentleman

TR_Jim
04-27-2006, 03:18 PM
One thing you might want to check for editing is the location of the overdrive switch. Mine (TR4A) is on the left hand side, same as the turn signal switch. I believe they were all on the left side. Or maybe that's another difference between a 4 and a 4A?

Kurtis
04-27-2006, 04:16 PM
[ QUOTE ]
The factory rally TR4's had their handbrakes relocated there (rally driver's use the handbrake to slide the car around corners.)

[/ QUOTE ]

That's interesting... and explains the handbrake location on my TR4 diecast model. I had assumed that the makers had confused it with a TR4A, but it looks like the interior (and engine bay) were just carried over from the factory rally car model that the maker also produces.

TR4nut
04-27-2006, 04:31 PM
[ QUOTE ]
One thing you might want to check for editing is the location of the overdrive switch. Mine (TR4A) is on the left hand side, same as the turn signal switch. I believe they were all on the left side. Or maybe that's another difference between a 4 and a 4A?

[/ QUOTE ]

Yep, that is a difference. The overdrive switch on the TR4 is on the right instead of the light switch. The light switch is on the dash. In fact, that is how I bought my first TR4 - I noticed it had a right switch even though the seller wasn't advertising the overdrive. Of course, he wasn't advertising the rust in the floor pans either..

Randy

Kurtis
04-27-2006, 09:20 PM
[ QUOTE ]
Of course, he wasn't advertising the rust in the floor pans either..

Randy

[/ QUOTE ]

<grin> I looked at one car where the seller said he had repaired a rust hole in the driver's side floor pan about the size of a quarter. When I looked at the car, I quickly realize that what he meant to say was that a quarter of the driver's side floor pan had rusted out! LOL

04-28-2006, 05:19 AM
[ QUOTE ]
[ QUOTE ]
Of course, he wasn't advertising the rust in the floor pans either..

Randy

[/ QUOTE ]

<grin> I looked at one car where the seller said he had repaired a rust hole in the driver's side floor pan about the size of a quarter. When I looked at the car, I quickly realize that what he meant to say was that a quarter of the driver's side floor pan had rusted out! LOL

[/ QUOTE ]

I like it when the seller says, "..some rust"

some rust = basket case



Bill