@Alan Merklin posted:Very easy to adjust a buggy tube chassis to a speedster, a few inches in the center will work. Acme in PA , VW Store in Drums, PA and Barrett in AZ all make nice bare chassis, they all are around $2,000 plus $350 for a bare torsion housing charge. By the time you add in trailing arm, beam, disc brakes, lines hoses etc. a complete chassis ( if you do the work) is just under $5k.
Although I believe the custom chassis are an improvement over a 60+ year old VW pan, they can make it difficult to register (especially if you stick to smog/polluting air cooled engines) plus they are costly. A lot of banged up Miata's are out there with modern engines, chassis, 6 speed transmissions and 4 wheel disk brakes - 50/50 weight distro to boot. All for easily under $5k. Tons of aftermarket pieces (springs, shocks, anti-sway bars, turbos, super chargers, brakes) too. Using a Subaru as a donor (like infamous SAS), where suspension, engine, trans - even wheels is good idea. Many have registered their plastic cars as the donor vehicle - wonder if you'll see Miata and Subaru registered Speedsters/Spyders?
Back in 60's MGA/TR3-4/AH chassis were used for FF kit cars (Avenger/Jamaica, Astra). Not a lot of them were out there even then. Pontiac Fiero were popular for Ferrari in 80's - again not that many out there.
Note- since the Miata is light weight with plastic bumpers, aluminum hoods and front fenders, it doesn't take much to total one. If the air bags go off, changes are good it becomes a potential donor car. Down side is - you won't easily convert one to rear engine config!