Some coupe questions

[pope]

welcome to 21's century

[Redline]

I'm searching for a 124 coupe, preferably an AC, but things are (understandably) rather thin, even over here in Europe, so I will probably have to expand my search to BCs as well. I have some questions.

1. The ACs lost the torque tube rear end in their final year, therefore I assume the late AC suspension layout is then comparable to the BC (and therefore not as delightful?). Or did the BC also delete a rear sway bar or something else to make it even worse? Information seems a bit sketchy. I have read generally negative comments about the handling of the BCs, but I am wondering how much would be required to set it right, if it really is so different from the AC. I am not looking for all-out grip or razor-sharp turn-in, as I'm already coming from an Elise-based car and now want the "classic" experience. But I do want something that isn't going to cock one wheel in the air and understeer like a pig.

2. The 1600 in the BC here has a twin carb setup (but no smog equipment), which apparently is not easy to set up and tends to drink gas. Now I know this is a US forum, so perhaps I'm asking the wrong people, but can a BC motor be properly tuned, or is it better to change out the setup for a single carb? Fancy side-drafts etc. would probably not get through the Swiss inspection, I imagine.

Thanks

[kmead]

1. The ACs lost the torque tube rear end in their final year, therefore I assume the late AC suspension layout is then comparable to the BC (and therefore not as delightful?). Or did the BC also delete a rear sway bar or something else to make it even worse? Information seems a bit sketchy. I have read generally negative comments about the handling of the BCs, but I am wondering how much would be required to set it right, if it really is so different from the AC. I am not looking for all-out grip or razor-sharp turn-in, as I'm already coming from an Elise-based car and now want the "classic" experience. But I do want something that isn't going to cock one wheel in the air and understeer like a pig.

Yes the AC bodies lost the torque tube in the final year. They also lost the rear anti sway bar (anti roll bar). If you read the old reviews many felt it lost some of its handling prowess but in reality it is not much of a difference, all cars from this era were benign under steering cars. One can add a rear bar but in doing so you need to also upgrade the front bar to 1" to balance the car out and prevent exactly what you don't want which is lifting the inside wheel prematurely. Given that these are open differentials you will not be hotting around all that much. The AC late suspension and the BC suspension set up is identical so choose the body that you prefer assuming you can find one. I have had both and tend to prefer the BC but not everyone shares my predilections.

2. The 1600 in the BC here has a twin carb setup (but no smog equipment), which apparently is not easy to set up and tends to drink gas. Now I know this is a US forum, so perhaps I'm asking the wrong people, but can a BC motor be properly tuned, or is it better to change out the setup for a single carb? Fancy side-drafts etc. would probably not get through the Swiss inspection, I imagine.

Twin IDFs (or the Solexs on some) are pretty much set and forget once they are setup and are the equal of a "fancy" side draft for the most part. Side drafts are hard to install on these cars as the vacuum booster and master cylinder both occupy space the rear side draft wants to be in. The fuel consumption difference between the twin IDF setup and a single is only going to be a few mpg/kpl and there is a significant difference in performance which I don't think you would enjoy. A BC with a 1608 is a wonderful engine (my BC has a single carb 1438 which is a bit less powerful but no less delightful) and can be tuned very nicely.

Keep in mind these are old cars, they don't drive like modern cars and offer no where near the performance a modern Lotus does. Which is not to say they are not fun cars to own, the coupes are very roomy and are great cruisers (aside from the short 5th gear) with an excellent ride and handling compromise. What they are not are fast autocross cars, stop light grand prix or a race car in standard trim.

Now with some enhancements they can certainly be much more.

Hope that helps.

[Redline]

Thanks for the very thorough answer.

I certainly have no unrealistic expectations about performance. I've been all over the map with cars and relative performance over the years. I have already had a Smart Roadster as a one-year "buffer" between the Opel Speedster (Elise chassis with 2.2L GM lump), so my "accelerative expectations" have been re-adjusted somewhat. You probably don't know the Smart Roadster in the US, but it performs about on par with a 1.6L MX-5, but with more grip and less "feel".

I have already driven a 4-speed AC and was more than happy with the power (or lack thereof), however it really needs a higher top gear, which leads me to 5-speeds. The thin-rimmed steering wheel, the "Italian" driving position and the generous greenhouse were a refreshing change. I am not looking at old Fiats with the plan to build a B-road blaster. I am looking to recapture a bit of my childhood, to have a retreat into a simpler era, and to enjoy some style. I would keep it on the narrow tires, but I still appreciate the difference between a neutral and overly front-biased car, even at less than Elise speeds.

Can't decide on the body. Both fit their era and each has their merits.

[kmead]

Great to hear. Unfortunate how few fun cars we have here, we did/do get the Elise platform and although I have been in a a Smart Coupe I've not had the pleasure of driving one.

The two cars are effectively the same aside from the sheet metal in front of the A pillar. The view from the driver's seat is the biggest difference in my mind, the BC has a more contemporary view across a simple planar surface while the AC has a more classic view down a sloping hood with peaks and valleys with the headlights leading the way.

From a styling perspective I really like both cars. The front on the AC is especially nice with the single headlights and the running lights nestled into the opening in the grill with the stainless wrapping around them. The only thing that bothers me about the AC is the way the body character line that runs along the side of the car is resolved near the headlight, it just sort of washes out oddly. The BC handles this much better in that area and seems more of a single piece of work.

You can't go wrong with either car as the interior is the same (one less gauge with a AC and no headrests on the early cars) and mechanically they are the same.

I do have one disappointment for you. Although the 5 speed brings an overdriven gear, it isn't a very different ratio (1:1 for fourth and .89:1 in fifth) so although it drops the revs a bit it doesn't really drop the revs all that much. The other side of that is the Fiat twin cam doesn't mind revving and keeping those revs up for hour after hour.

Good luck in your search and please keep us informed. There are not many left here and few people here post about them.

[Redline]

the AC has a more classic view down a sloping hood with peaks and valleys with the headlights leading the way

Exactly what I liked about the Speedster, the Smart Roadster and also the 911 that I flirted with. It just adds a level of interest to the view and also makes it more satisfying to place the car on an apex etc. Then again, I also agree that there is somehow something not quite right about the way the front works with the rest of the car.

There are not many left here and few people here post about them.

Even here they are thin on the ground. The good ones go by word of mouth, and the truly good ones are priced accordingly. This one is lovely (with extremely rare Abarth wide steel wheels), completely original, no rust, a true time capsule. The price reflects this (>15'000 USD). Bit rich for me, but then again the completely clean body may just be worth it, compared to trying to get a worn one back to good shape.

[Curly]

...... But I do want something that isn't going to cock one wheel in the air and understeer like a pig.

It takes a fair bit of provocation to get an AC to cock a wheel in the air, but they don't 'understeer like a pig' even in standard trim. Mine's an early torque-tube model with a later BC1600 twin cam with twin sidedraft Webers and 5 speed, but I guess the Swiss authorities, not to mention left-hand-drive, would make this arrangement very difficult for you.
Any of the Coupe's built-in understeer characteristics can be tuned out with camber, castor and toe adjustments, even tyre pressures will have a noticeable effect. The BC rear end is similar to the AS, BS, & CS Spiders and although looked on as inferior by early AC owners , it's still a very well set up live axle by contempory standards. Fitting a rear sway bar to this later setup will help induce oversteer and unless coupled with lower and stiffer springs with a good set of shocks, you may find the inside rear wheel lighting up in tight corners.
ACs crop up regularly Down Under, most are basket cases, but there's still some good ones around that aren't that expensive.

[Redline]

Good to hear. Your car is what has fueled my interest in the Coupe and the AC specifically.

[Curly]

Good to hear. Your car is what has fueled my interest in the Coupe and the AC specifically.

It's sometimes useful to have someone to blame

[WarbirdAL]

this thread and those pictures got me all excited. I still have my early 69 (12/68) in my garage with the cylinder head off. I got a rebuilt head from Mark almost a year ago but have been afraid to put it on wrong. Done that to my first Fiat years ago. The aux timing shaft alignment has got me all confused. It is the 1438 cc with the 4 speed.

[Redline]

Follow up....

After looking at several rough ACs, and not finding the time to get to Cologne to look at another rather promising one, I decided to get my feet wet with a good, solid '72 BC. It's not a time-capsule beauty queen, but seems generally very good. The minor interior and exterior blemishes I can deal with. I was happier that the 1608 motor pulled strongly and there was no obvious signs of rot. Clean, thin seams everywhere and lots of good metal overall.

Ask me again in two weeks when I've titled it and picked it up for the 250km mountain drive home if I am still so pleased...



Maybe there is still an AC in my future, if anything to get a car with the same "birth year" as mine(68), but the BC styling has really grown on me. As commented before, the front and rear are perhaps a better match, with the forward rake of the nose complimenting the rear rake at the back.

So, for now it's bell bottoms instead of mini skirts for my wife...

[kmead]

Very nice indeed, its the same color mine is, although yours is actually shiny and doesn't suffer from various and sundry dents, bobbles and a mix of greens from different bodgy repairs.

Congrats. Feel free to send it over here if it doesn't meet your expectations.

[ROOK1]

Bump to the correct century.

[sptcoupe]

I have had at least one coupe in our household since 1973, and have always preferred the BC, but that is strictly a personal preference. All three are great GTs. As to handling, I have found that there is not much difference between the stock AC and BC models, especially in street use. I have also found the best suspension set up to be 1) lowered (and stiffer) springs, 2) a rear sway bar, 3) good shocks all around (but I like Konis at the rear and KYBs at the front), and of course, 4) the best tires you can afford and that are best suited for your style of driving. I have found that the above set up tightens the rear end up quite a bit against the front end, and eliminates the natural understeer of these cars, making then a pretty neutral handler. If you don't lower it, then I would recommend a larger front sway against the added rear sway bar and stiffer shocks in the rear. For my tastes, the lower (and stiffer) springs eliminate enough sway/lean to make it more than adequate for the street, without needing a heavier front bar, and the tighter rear end eliminates the understeer. I have found that a heavier front bar improves body roll in corners, but basically undoes anything you have done at the rear to eliminate understeer, so you end up with a car that stays nice and level in corners, but still undertseers. This is not all bad, just a matter of preference as to what you are looking for. The point is, you can set your BC up to out handle any of the three models in stock form.

The 1608 with a good header (get one of Mark's) and exhaust all the way back, with mild cams, really brings out the best in the dual IDF set up for street use, but you will have to re-jet the carbs a bit (not difficult to do). You may also want to install a good electric fuel pump and a fuel pressure regulator to ensure you get a consistent fuel supply delivered at 2.5-3.0 lbs. The 9.8:1 CR will work just fine. Finally, converting to an electronic ignition will eliminate some tractibilty issues and let you enjoy the extra rpms you will get by letting the 1608 breath more with the cams and exhaust.

Your coupe looks really terrific. Enjoy the car and keep us posted on what you decide to do, and let us now if you need ideas or help.

[Redline]

Thanks for the tips. You've roughly described my plans. One small challenge here in Switzerland is that classic cars can be granted a special classification, which this BC has, where inspection is only required every 6 years (instead of 2) and insurance and tax is lower, however the car has to remain "original" and in "excellent" condition. The definition of both is subjective and somehow at the whim of the inspector, but often they are very knowledgeable. So you get into little discussions back and forth, where replica Cromodoras would be considered original but Minilite copies wouldn't etc. A conversion to sidedrafts would not go through.

Classic status permitting, my goals are (chronologically):

Enjoy the car as is on dry weekends this fall and winter, eventually packing it away.

Install intertial seatbelts. Try to find lowback seats with headrests (but this could be tricky with keeping the "classic" status). Both are to satisfy my own and my wife's objective opinion on passive safety.

Electronic ignition.

New dampers. The back end is already a little nervous and there is some axle tramp in 1st gear; my feeling is the dampers have gone soft. I had already found the Konis... I am surprised and intrigued that you suggest mixing and matching KYBs and Konis. Not sure if I would lower the car or look at ARBs (sway bars). I'll see what my impression is bit by bit.

Wheels and tires. I'm tempted to move to 14" Minilite replicas to open up more options on rubber, but I'm not convinced by the look. Another option would be the lovely 13" Cromodora replicas that Compomotive makes, but they're pricey.

Eventually rework the sills / rockers. At the moment they are painted with black rubberized paint, which for me doesn't help the aesthetics. I want to repaint them in body colour. As far as I can tell, everything is very solid, but I would still be prepared at that point to address any surprises I find.

That's about it. Not looking to make a tarmac rally winner ( ) but just an enjoyable little Italian plaything.