Looking at a 55 Cadillac dual quad engine but to be honest I dont know anything about them. Any pros or cons to this engine and any transmission options for it ?? Any known problems, what to look for ??
Pro: They are well designed engines. Have good stock replacement parts availability, and are are cool looking. Con: They are expensive to build. Aftermarket speed parts can be tough to find and expensive as well. However, the speed parts availability is getting better. Try Bendtsens or Wilcap for transmission adapters.
Cons: limited transmissions without an adapter and are prone to cracked heads. I've found out first hand that finding used heads that aren't cracked is quite a challenge.
One of the best built engines of the time, quality far superior to any Ford or Chev. 331 cu in about the same HP as a Chev 350 but weighs 100 pounds more. I would rather have one than a Chev, but from a practical and economical standpoint, the Chev is better.
Lots of the 2-4bbl. setups got pulled due to neglect. The Carters caught fire a lot in cold weather, & the air cleaners are scarce. When in tune, you'll never forget the sound. A fresh dual range hydro built to Eldorado or 86 series specs is all the trans you'll ever need ...
The '55 dual-quad (Eldorado) transmission used some parts in it that the standard '55 Cad trans didn't use... don't ask me to look all that up now though, I have sold all my literature off. But at least one of those parts was thin .055" (or so) friction steels that allowed for extra clutch discs to be installed. Shameless plug: I actually have some of these thin friction steels for sale at present (see my older ad in the classifieds if you need some).