Ideas for making the Pantera lighter?

Peter, 1320Kg is very heavy for a track car. Many factors are at play when it comes to performance and lap times. Power to weight ratio is a big one. High weight adversely affects cornering and transient response. Heavy track cars need huge sticky tires and tons of HP for decent lap times compared to lightweights.

Taking weight out of a street car is a challenge without chopping up the car. Will your car still be used as a street car or will it be track only? That's the first question that must be answered. The second question is how far from stock do you want to go? Then, how much money do you want to spend?

I'm building P#5715 as a street car. I'm a firm believer in lighter is better but still want some comfort. I guess I'm showing my age by that comment. AC and a comfortable interior are included in my build. For weight reduction the car is getting an all aluminum Clevor engine, aluminum rad, fiberglass front and rear deck lids. I have no idea what the car originally weighed because I bought it all apart. I'm hoping to be down to at least 2800 pounds.

I considered buying a lightweight (Lotus) for the street but I couldn't resist the Pantera's good looks.

When I was working in aerospace, the company rule of thumb for weight reductions within a given design was about $1000/lb removed. An article on automotive design once said Detroit's costs in the '90s was about $100/lb removed. So your costs for making a 45-year old sports GT lighter will likely be somewhere in between those two numbers The more you can do yourself and the more patience you use, the closer to the low end of the range your project will be, I suspect. Decades ago, my goal for a laregly unaltered narrow body '72 Pantera was 2650 lbs, and I am now at 2690lbs with a 50-lb lighter aluminum block in the garage, waiting for the $$$$ to finish it. So that number seem within reach but remember, I have an pretty well equipped machine shop in my garage and I've been at this on our Pantera for 28 years & owned it for 38 yrs. We will NOT talk about how much money was involved!

I am using it for both. Street and track.
The problem is : how to lighten it up and be safe about homologation rules from FAI .
How much weight we can safe with aluminum doors , hoods ec. ?
How can the older gt4s have less than 1000 kg ?

I believe that the race weight of the Gp4 cars was 2650 pounds, 1202kg's. (Maybe the reason for BW's goal? )

That's with the aluminum skins, plexiglass windows, and all of those holes punched in the chassis.

The drivers were like horse racing jockies, all 125 pounds or less. Jackie Stewart. Mario Andretti types.

When Ford evaluated the Pantera for racing, weight and serviceability were negatives in that evaluation.

The 289 Cobra is 2,200 pounds. The GT40 is lighter.

I don't think you can get the car down to 1000kg's? You can't acid dip the body.

With aluminum heads and block you can save about another 150 pounds.

If you want to keep whitin FIA Homologation rules, 1220Kg is the limit.

Se bottom of page #2:
https://historicdb.fia.com/sit...ber_3047_group_b.pdf

Don't know the level of truth in this, but it could answer your question about the older Grp4 cars being even lighter:

"While a projected weight of around 1100kg had originally been targeted, Porsche were so concerned about the Pantera’s arrival that they forced the FIA into homologating the Group 4 version (or GT4) at 1250kg"

Source: http://gt-cars.co.uk/1974-de-tomaso-pantera-group-4/

Peter, I don't think 1000kg/2200lbs is realistic for a Pantera- even a fully dedicated racer. If it did happen, I suspect it would no longer be a real Pantera. Note the popularity in the '80s of tube-frame composite body replicars; I do not regard 800 bhp Kremer-Porsches as 'real' cars, either. And its easily possible to go too far; a Swedish friend got his Chrysler Hemi-powered steel street Pantera down to 1100 kg but major suspension parts failed from one off-track excursion during a club event, wrecking his car. Haven't heard from him since.

I haven't looked at FIA vintage rules lately (they change every year and I no longer compete). Most here are interested in street-drivable cars so that puts even more limitations on our combinations. My 2650 lb goal was for a street-legal Pantera with two seats, a radio, heater, A/C & e-brake, no roll cage, and smaller tires and wheels with no fender mods than are permitted for racers. Those things weigh an estimated 200+ more pounds that a racer doesn't need.

In addition, I use a 'heavy' L & N fiberglas front hood that I found too late was only 5 lbs lighter than stock steel. Today there are shops that can put together hoods, decks & doors from carbon-fiber and be 50 lbs lighter just from those. They are nowhere near as cheap as my L & N hood was but there are scams even here. Rear suspension uprights made from light alloy have been available for a decade that are 12-14 lbs/pr lighter than stock iron, and the list goes on. 2500 lbs/1130kg should be achievable for a self-financed home-built racer and maybe less with a pro-built cost-no-object machine, but as I said in my POCA Newsletter article last month, the big weight losses are in the powertrain & suspension, not in the sheet metal. Good luck- J DeRyke

just as a smile point on my raceing (push-) bike earch gramm was app 1.5 € - 2 @

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Matthias