STAGE III The STAGE III (3) manifold was a true "sleeper" in that it was over 2" LOWER than the original Weiand tunnel ram, while still possessing all necessary runner lengths and plenum volume for balancing the carburetors and their reversion waves. What is worth noting with regard to today's similar "fabricated" designs, is that Jim developed this in 1978!	STAGE II Developed in 1973, this was more conventional looking, but still a heavily modified manifold with extensive runner work used on on the 9,300 rpm B/MP Mustang. The original Weiand Plenum was sectioned to reduce size. The cast wall with Weind's ID between the runner groups, served as the floor to the new plenum on the STAGE III PRO Model (shown below).

Most people today know Jim Miller only from the "MID-LIFT" patent and development of the precision geometry rocker arm. But Jim's original first love was cylinder head and intake manifold development, all stemming first from the BOSS 429, then graduating to all the popular engines as word got out that a small shop in the middle of the Midwest was breaking new ground. Small block and big block Chevy and Ford were all routine projects, including Ford's FE and Cleveland engines. Harley-Davidson 750 race bikes and Teledyne Continental Aircraft engines have all been contracted for flow development to Jim by their top shops from all over the country. The manifold shown here could easily have been fabricated from aluminum sheet and tube, but was purposely left looking as close to "stock" as possible. Its inside dimensions and laid over "D" shape roof was massaged to a cross sectional area equaling the 2.40" valves for near perfect laminar flow, thanks to heavy back side welding that added more than a solid half inch of Mig laid material. The ploy was chosen because there was another school of thought on intake manifolds that supported "IR" (Individual Runner) designs, which Jim did not subscribe to. Like many engine builders of the time, it just as important to mislead competitor copy-cats as it was to win competitions. So Jim's intentions was to fool the occasional onlookers studying his engines with believing that he used an IR manifold, when in fact his hidden plenum was anything but an IR.

STAGE III This shot shows the first welded plate between the two four-groups on the back side of the center name plate bridge, tacked in place. Not seen, is that the huge "V" on the underside of each of these four group runner towers that have been welded with more than a 1/2" of material  to allow machining out the floor to remove the arcing of the runner, make it more of a straight shot, and enlarge to the cross sectional area required.

STAGE III NOTE difference between runners on lower left, compared to roughed out runners in the upper right, especially the depth of the floor, and thin wall of roof, by comparison. After the side plates are welded in place between the runner groups, a mill is used to machine out the V until the bottom is even with the floor plate between them, then the arduous task of opening  and hand blending the ports is begun. Not shown is that the backside of runners is welded to provide material for enlarging.

 

STAGE III This shot shows the welded plates between the two four-groups of runners, to seal the "V" bottom once a top cover is mounted. Straight shot of the runners, as well as their massive size is easily appreciated.	STAGE III After the plenum was finished, a 1/4" aluminum plate with 1 inch solid Dominator spacer blocks was fitted. The original dominator mounting pattern was kept on the manifold to allow easy disassembly for cleaning. This was a $2,000 manifold in 1980 dollars. Which would easily be over $4,000 today in 2011 -- 31 years later.

MILLER PRODUCTS GROUP 1775 NW 30th Ave. #413 Pompano Beach, FL 33069 USA 954-978-2171 "MID-LIFT" & "PRO-SHAFT" are ® Registered Trademarks of MILLER ENGINEERING INC; Copyright © MMIII - MMXI JM Miller