Working out the bugs:

7-1-2010: The Roof 101 Cyclone is a very tightly designed piece of equipment, but as with all new things some little issues arise and need to be changed or explained.

1: ROCKER ARM GEOMETRY: Setting up the correct pushrod-adjustable lifter length can be accomplished SIMPLY by using the Manley pushrod length checker # 42132. This is a simple plastic tool that you push down over the rocker stud until it touches the top of the valve stem. You then adjust the allan bolt (push rod seat bolt)  in the lifter (Tappet) until the top of the pushrod touches the other side of the Manley tool. This easily produces the correct pushrod length & rocker arm angle. It is recommended that owners avail themselves with this tool to make installation a snap. It not absolutely necessary it just makes it easy. Available at www.Summitracing.com get one for 7/16" studs . . . about $10.00.

       photos by Dennis Piranio

2: PUSH ROD SEAT BOLT: In practice, we have found that our 1-1/4" long pushrod seat bolt (3/8-24 X 1-1/4" allen head cap screw) is the right length for all normal street driving WHEN bottomed out to about 15 lbs of torque into the adjustable tappet. Torqueing too far can "fatten" the tappet and must be avoided. When using the above noted "Checker tool" you may find that a bolt about 1/64" to 1/32" longer would be nice for the theoretical perfect blue printed geometry. These custom lengths are not available and will have to be made up from longer bolts. Take a 1-1/2" bolt and grind it to the size you want is the trick . . .  a lot of trial and error but you'll be on the right track. . . .  OR

It would be best to have a jam nut on the "push rod set bolt" wrenched against the tappet (10 psi) to securely lock it to the proper length. These nuts must have 3/8-24 X 7/16" flats verses the larger 1/2" wrench flats. The larger 1/2" flats will hit the tappet bosses.

These SPECIAL 3/8-24 JAM NUTS are available from the "Jessel Company", phone 732-901-1800, cost is $3.60 each nut plus postage. These are normally used in older Chrysler engines.

Note on tappet Bosses: Some engine builders machine off the tops of the tappet bosses. Probably no two shops cut the same amount off. The only reason I can think of to do this is to use the "Double Locker" adjustable tappets, which do not rise far enough to adjust the "jam nut" unless the bosses are shortened (The Riley or Roof will not work with "double locker" adjustable tappets - their thread size is too small). This boss shortening is problematic due to the sideways force caused by the rotating camshaft and could (probably will) prematurely wear the tappet bore down to an oval.

HOWEVER, if your block has this modified shortened feature, a normal 3/8-24 jam nut might be used with the push rod seat bolt . . . If the nut does not hit the boss on the downward stroke!! Normally, you will need a special smaller OD jam nut (with 7/16" wrench flats from the Jessel Company). DO NOT USE Double Locker adjustable tappets, they are not sized correctly for use in our OHV equipment.

3. VALVE COVER SEALS: The four valve covers are presently sealed with a large O-ring fit to a machined edge and a neoprene bonded washer under the acorn nut. The O-ring has given trouble in the field. Not leaking, but being too slippery to work with easily. We are having new cork & rubber gaskets made to solve this problem. Future caps will not be machined as the surface "as cast" is correct. THESE 4 PARTS, WHEN DONE, WILL BE SHIPPED TO ALL OWNERS. . . . . 8-10-10 I have the new gaskets and will ship in mass next week.

4: INSTALLING INTAKE MANIFOLD:  the Roof intake manifold should be installed in this order: hand install bolts to head to be sure they turn easy by fingers. If any are tight chase the threads (shouldn't be needed).

Install one gasket to each port held with two upper bolts/lock washer threaded in about 2 threads deep (loose). Hold the manifold level and pull it out to the upper bolts and  slip in a bottom bolt/lock washer to about 2 threads. When all bolts are in place start tightening by finger a little to each one until all are seated fairly evenly. Bottom bolts are a tight fit by the manifold's curves. But if the install is done in this manner it will fit together nicely.

HOT TIP: Install the spark plugs first. There is no room for a socket wrench after the manifold is installed. An open end wrench can be used.

5: ROOF CARBURETOR ADAPTERS: The Roof aluminum adapters were nicely machined but should have been tapped. The holes are slightly over sized for this but will tap nicely to 3/8-18 and do hold 20+ pounds of torque. This requires drilling out the carburetor's mount holes to 3/8" to fit the bolts. Also, of the 3 carb mount holes in the adapter, the single center hole will require some tweaking to get the bolt to slide into the hole. A little filing to the hole and little to flange lip. This will be corrected in future casting/machining runs.

6: LASH BREAK IN: There are reports of the lash changing after 100 mile check up. This is normal on OHV conversions. The gasket will compress (you did re-torque didn't you!); the push rod seat bolt will settle in; the valves will settle in . . . etc. So, after 100 - 200 - 300 miles double check your lash. Any change after that should be minimal and not require adjustment until 1000 miles (+ -) .

7: (8-1-10) WATER PUMP FIT: It might be possible that the "short" 1933/34 version of the Model B water pump will work better and with a longer shaft. I have one report, "that the fan hub hits/rubs on the "long" 1932  pump housing." This seems to be a factor/issue of shaft length.   

It could be a mount-flange thickness issue on the head. Check fit carefully. The head's mount could be machined up to 1/4" without harm to get things lined up. The pump's rotor end is to fit into the counter bore inside the head. The pump's fan-hub-pulley is to line up with the crank pulley/generator without touching the pump body. Test fit without a gasket by placing a straightedge on the crank pulley, up to pump pulley. Adding the gasket gives the correct clearance.

8-20-10: It has been confirmed that the pump mount needs milling of 1/4" (+-) off to make pump to crank pulley alignment perfect. This minor alignment issue has not affected the test engines or those running at this time. Future production will be corrected.

8: (8-10-10) LASH SETTING MADE EASIER: Jim Newcomb, Maryland, has discovered that setting the Roof's lash is much easier with a hardened washer, 5/8" OD X 7/16" ID X 3/16" thick, placed between the rocker lock nut and the polylock nut. This gives more room for the wrenches to fit and does not cover up the oil hole.

9: TIMING GEARS: I can not over emphasize enough the importance of using a metal timing gear. The fiber gears are not strong enough to guarantee integrity with high pressure valve springs. There are aluminum and bronze timing gears in the market. The Bronze is strongest and runs quieter. The aluminum job is strong but make no mistake, the cam nut must be torqued to 125 pounds. Just don't take a chance with a fiber/plastic gear.

If you discover a problem or have a "hot tip" please contact me.