Miller 91: Complete (#14 for 2018)

A challenging little kit, but well worth the time. The Miller 91, whether FWD or RWD, was an inspiration to many, including, if the stories are true, one Monsieur E. Bugatti. And while the Miller company didn't survive the '30s, his engine design did, in the form of the fabled Offy motor designed by his cohort Fred Offenhauser, and derived from the Miller design.



The kit is a difficult build, given the assortment of unlabelled little bits and the enigmatic instruction sheet. There were some problems. A lot of bits, while very detailed, are minuscule and can easily vanish. (My build is currently missing the wind deflector). The kit appears to be missing a couple of filler caps (oil, water); the amount of 0.025" nickel rod supplied was sufficient for the shifter linkages but not the steering linkages; getting it to sit square is critically dependent on getting the front suspension right (a task at which I failed). I'm looking for Firestone Balloon decals for the tires, which would have been nice to have in the kit. And there are a couple of unidentified bits left over. On the plus side, the quality of the resin cast bits is superb, and HRM owner Harold Bradford is obviously very knowledgeable and keen. 



Nonetheless, the Miller will sit nicely next to the other members of my open-wheel fleet, such as it is: its spiritual successor, the Kurtis short track racer, and the 1.5 litre Honda RA 272 from 1965.  



Sporting a pair of Strombergs, high compression heads and assorted other hot rod bits, the Ford flathead motor in the Kurtis likely made somewhat more than the 125 hp put out by the stock 255 cubic inch (4.2 litre) version, circa 1952. (I have an Offy-powered version in the stash). Optimistically, let's say 175 hp, or about 42 hp/litre. 



Honda's RA272 had a 1.5-liter V12 made around 230 hp in 1965. This was state of the art for GP motors in 1965, at about 150 hp/litre.



The Miller 91 (91 cubic inches, or 1.5 litres) made as much as 250 bhp at 8,000 rpm, as early as 1926. OK, it was supercharged and intercooled, and ran on methanol, but this is still an impressive 167 hp/litre, especially for a small bore, long stroke motor. And it was FWD to boot, offering a low driver's seat and the ability to power out of turns without lots of oversteer. It is interesting that Bugatti likely copied the twin-cam, hemi-head engine, but not the FWD layout.



By way of comparison, I have a Renault 40 Record kit from Profil 24; this 9-litre land speed record car made a measly 130 hp in 1926, for 14.4 hp/litre. Unfortunately that kit is curbside; it would have been interesting to see and build the Edwardian monster under the hood. Perhaps I need to get my hands on the Fiat Mephistopheles kit from Italieri...



So there you have it: world-class technology from the late 1920's, in a very detailed but challenging little kit. I expect similar adventures with my other HRM kit, the brutal little Cheetah from the mid-Sixties. 



Stay tuned!