17 replies to this topic

[masterpiece]

Hello friend
I serach others images of this beautiful 911 Targa IMSA.
Raced at Glen in 1980.

Thank you for help me.

[jm70]

This is a SCCA B Production car. You might search SCCA results, or Paul Overby. Good Luck

[Terry O'Neil]

You could try the Watkins Glen Motor Research Centre, they might retain photos as this was a local race.
Terry

[EDWARD FITZGERALD]

I have a1/43 scale model of the car ( handbuilt) , cant remember who made it .

[CJE]

I took photos of this car at Watkins Glen in 1979 or 80 (6Hr World Championship for Makes, I think). I will scan them and post later. -- Curt

[masterpiece]

The modelcar is made by my friend Fabrizio Pitondo (PIT MODEL) but isn't very correct (he worked only by image posted).
I want realized a good model for my collection.

[masterpiece]

Have good news?...

[masterpiece]

... Sob ... Sob...

[CJE]

Is this it?

[masterpiece]

Oh Yes, YYYYEEEEESSSSSSS !!!!

[BRG]

Can anyone tell me WHY anyone would want to use a Targa? They must be really floppy compared to a 911 coupe, and I think they were heavier too. Was it something to do witth SCCA class rules maybe?

[CJE]

No roof, no glass = big weight savings (at the top where it counts). Roll cage provides stiffness.

[CJE]

Another photo from a slightly different angle ....





This is from Road America (Elkhart Lake), 1 year earlier than Watkins Glen. Maybe the same car??? Still has windscreen and A-pillars intact here ....




PS - sorry for poor quality scans! There are on transparency film and I do not have an adapter for my scanner right now.

[masterpiece]

Thank you CJE for precious images.
Very interesting too the second version.

If you can send me by mail your postal adress, I want give you a little present.
adami@adverperformance.it

[ggnagy]

Originally posted by CJE
No roof, no glass = big weight savings (at the top where it counts). Roll cage provides stiffness.

Less frontal area too.

[BRG]

Originally posted by ggnagy
Less frontal area too.

With the windscreen still in place, it would the same frontal area as a 911 coupe. But the big hole in the top would give far more drag, I reckon.

I still think it must weigh more. Convertibles like this require massive floor beams to restore the chassis rigidity and those weigh a lot - and are rarely as effective as a full monocoque body shell. And back in 1980, that piddly little roll-cage would probably have been a bolted-in job rather than an carefully engineered welded-in cage picking up on the suspension mounts and acting as a spaceframe, as you might find in current cars. So I doubt if that gives much extra rigidity. So I still reckon it must have floppy compared to a 911 coupe

[ggnagy]

Originally posted by BRG
With the windscreen still in place, it would the same frontal area as a 911 coupe. But the big hole in the top would give far more drag, I reckon.

I still think it must weigh more. Convertibles like this require massive floor beams to restore the chassis rigidity and those weigh a lot - and are rarely as effective as a full monocoque body shell. And back in 1980, that piddly little roll-cage would probably have been a bolted-in job rather than an carefully engineered welded-in cage picking up on the suspension mounts and acting as a spaceframe, as you might find in current cars. So I doubt if that gives much extra rigidity. So I still reckon it must have floppy compared to a 911 coupe

The windshield vs open cockpit drag argument has been a neverending one amongst SCCA production car club racers. Many very good engineers and drivers have worked very hard to get as much as they can out of the airstream. Even if it is a wash, the lower center of gravity argument goes in the open cockpits favor. Along the same lines, the coupe versions of the MGB and MGA all but disappeared from club racing at that time, while the roadsters have soldiered on. There is one MGA coupe raced, and it was given a weight break over the roadster. Up until recently, the Porsche 356 was in the same boat.

The semi-tube frame chassis was actually well on their way in to SCCA club racers by 1980, and were definately welded in. There was an article in the 1975 ARRC program, showing just that being done to the Bob Sharp Z car. I can also remember my uncle having a C Sedan mini that was semi tube frame back in that era. Also, I don't think the production part of the SCCA general competition rules required anything more than a 4 point roll bar with diagonal, and that 911 has at least 6 points. It also has a high door bar as seen in the first photo. the existance of both items hint towards a semi-tube frame.

By the 1970s, the participation of pseudo-factory teams had forced club racers to not only be good drivers but good engineers as well.

[CJE]

The weight difference between 911 coupe and Targa is minimal - maybe 100 pounds total, at most. There is no heavy opening mechanism as in a traditional cabriolet. The top is a vinyl covered steel frame - probably around 40 pounds - and easily removed. And there is very little added reinforcement in a Targa, compared to a modern cabriolet - just the roll bar, a small steel cross bar (maybe 2x5 cm in cross-section) under the dash and some floor pan reinforcement in the corners of the footwells. The Targa is more flexible than the coupe precisely because there is very little added structural reinforcement. I own a Targa.

I also own an e46 M3 coupe. There is a BIG difference in weight between it and the cabriolet version of the same car. So much so, the 0-60MPH time of the coupe is 4.8 seconds and the cab is 5.4!!!

Getting back on topic, I suspect this 'experiment' of using a Targa for fairly high-level racing did not work. Otherwise we would have seen many similar layouts. Racing Targa's throughout history can be counted on one hand!