A 1 5S’f IN SEVEN MATTERS

Sir, Replying to Mr. Woodbine re the conversion head for Austin Sevens, the conVerSi011 Was known is the L.A.P. head. WI LiCil was reputed to be of French design. These were fitted to the BoydCarpenter super sports model, together with a different camshaft, and were in production up to 1932. A top speed of 70 m.p.h.. was claimed by that eoncern fOr this modcl. Although. the head does give a better performance it leis its draw backs, and these :Lre Hutt t hind gaskets supplied with the licad :ire of the C :rind A type and blow frequently as head studs were not used, but long bolts. which did not nip. also tht• roeker ttear Wa,

oiled from ii pipe whicht was litken froiii the oil gauge main pipe and, owing to t he low pressure on the Austin. when hot the rocker gear was starved of oil and cattsed tappet wear, wl ich. ref mired eimstant attention. TheSC were the faults I found on lit I irig a licw conversion set in 1932 Itut after modification it was fairly reliable. but did roil improve the top speed by any great margin. In my opinion the side-v:ilve scores from the. ntaintenance point or view. As to producing an o.h.v. lwad t.r the market, the design is out Of date mid not a .good one at that, as the ports were very crude, apart from the very heavy weight of the head as a unit. An o.h.v. Itead in higlidilly alloy with shrunk valve inserts and 90-degree valve angles, with push-rods and a single down-draught carburetter centrally mounted might be more in keeping with present-day demands. I mn, Yours, etc., Kew Green. L. M. WILLIAMS,

CaMbridge Eng. Works.