Never Bolt on Off the Shelf Heads without inspecting them...

[rick m]

When I first bought the CHOP TOP I have, it had a 1776 in it that the owner stated was a real quality motor.  That was my first hint to tear it town and go through it. I never run someone else's motor anyway and had planned to take it out and build a bigger driver motor.

When disassembling the motor, I found the cardinal sin that many novices never know to check.  While the heads had 40mm x 35.5 seats and valves, the heads had stock ports.  The heads were not cracked and still usable so I disassembled them, bored them for 94s, hemi cut them and proceeded to blend the ports, clean up the conmbustion chambers and prepare the heads for the 1914 I was going to build.  I attached before and after pictures of the ports so you can see how choked they were right from the HOT VWs magazine vendor (which shall remain nameless).  Needless to say,  the big valves were not doing a whole lot because the advantage of the larger valve was not fully realized without blending the ports and doing a little more work to the head.

Now, after reworking them and before putting in new guides and having Mike Fischer run the valves for me,  they are killer on my 1914cc engine.  The motor ended up at 8.0 to 1 compression with the specs below.  It averaged 30+mpg on a recent road trip from Phoenix to Jerome, over to Prescott and back through Wickenburn into Surprise where I live.  The motor turned out great and gives me driveable, fun road trip horsepower while maintaining 180-185 temps at 65mph and averages 195 to 200 at 75mph. The motor recovers and runs cool when I back it down to 65 mph.

MOTOR SPECS:
94mm Cimas
69mm Tony Mance counterweighted/wedgemated crank
Old RIMCO Super Rods
New Case (AS 41 Dual Relief)
Full Flowed
SYSTEM 1 Filter
ENGLE 110 cam
SLR Lifters
Special Lifter Bore treatment by Steve Hollingsworth for better oiling
26mm Oil Pump and BERG Full Flow cover
Stock Rockers with solid shafts
Aluminum Push Rods
Dual Port heads/Hemi Cut at CE and reworked by ME (Valve Job by CE)
Dual 44 Webers (145 mains, 200 Air, 55 Idles, F11 emulsion tubes, 34mm venturis)
CB Manifolds (match ported) CB Linkage and Air Cleaners
COMPUFIRE Dual Coil Electronic Ignition and Wires
Deep Sump
Auxilliary 12" cooler and thermostat controlled fan (at 180 degrees)
13lb flywheel (wedgemated)
KENNEDY Stage 1 Pressure Plate
SACHS metal woven clutch disc

The motor is a dream with driveable horsepower around town and freeway power, still giving a lot of cars a run for the money the first couple gears.

Rick M

[rick m]

Here are some additional shots of my reworked heads for the 1914. Nothing big or special...just efficient. The heads had 58cc, zero deck with a .060 copper head gasket used and the compression ended up at 8.0 to 1.

Rick M

[rick m]

Here are yet another couple of simply cleaned up ports and chambers for good results from off the shelf heads.  These are my exhaust ports on the 1914cc motor.

Rick M

[bugnut68]

Rick, I bought a set of semi hemi cut 040 heads (stock valves) ported and polished about five years ago from you, you had an ad posted on the Samba... they're still serving me very well on my mild 1776, just thought I'd give you an update.  I only have about 5K on the enigne, as I don't drive the car daily much (especially in Lake County, Oregon winters!) but it's been a real fun street and bracket racing motor!

Ryan B.

[Jim Ratto]

not to mention off the shelf heads are never ready to run with a bigger than stock (even the little Engle 110) cam.
It only takes a few hundred miles for those keeper grooves to burr up.... and it only takes 15 minutes to pull heads down and trim keepers. Springs heights should be shimmed too, especially with the recent trend to run high performance cams on high ratio rockers.

Using heads off the shelf is like buying a box of cake mix and just sticking the un opened box in the oven.

[j-f]

Jim, could you explain how you shim the springs? 

[Jim Ratto]

Jim, could you explain how you shim the springs? 

here you go!
http://cal-look.no/lounge/index.php/topic,6122.0.html

 

[j-f]

Jim, could you explain how you shim the springs? 

here you go!
http://cal-look.no/lounge/index.php/topic,6122.0.html

 

Thanks Jim. 

[67worshipper]

rick ive got mike fischer 044 heads with extra porting work done by steve hollingsworth.im thinking theyre pretty good even though ive not seen them

[Jim Ratto]

really, nothing should just come out of the box and get bolted on or in the engine, without checking it first. Valve springs, rods, gears, bearings... all of it is suspect. Stock motor, ok... but a higher performance motor requires a fine tooth comb.

[Brian Silva]

This topic brings up great things to look for. Anyone have a source on engine building tips? The more knowledge the better!

[rick m]

Hey Ryan...great to hear you are putting those heads to use.  They were perfect for a small engine and some extra usable mid range power.  Glad they are working well for you.  I agree with Jim Ratto...I did not mention keepers and other mods he did but we all do the same thing. Nothing off the shelf is ready to run.  The differnce in a reliable and well performing motor is in the details and all the little things matter.

As a proponent of long lasting, driveable horsepower that you can take anywhere, every motor type and use has different things you can do to it.  The items Jim mentioned should be done on any motor of any horsepower.  We never find spring rates that are identical in a set of springs.  More often than not, we end up shimming them.  I evel like to use a shim to have a buffer between the base of the spring and the spring seat.  It allows the shim to buffer the spring pressure against digging into the seat pocket.

There is a lot of motor knowledge in our hobby and nothing about it is sacred.  I share stuff with everyone I know...about motors I've built and driven anywhere. My favorite trip to dispell the myth of undependable big motors was when we did the BERG CRUISE to Michigan in 1997.  Art Thraen (ACE VW, MR. IDA), Don Bulitta and I, all drove big displacement street motors to Detroit and back.  No jet changes, dispite a myriad of weather conditions, temperature and weather. Our big motors were more dependable than some of the stockers, we all averaged in the mid 20's on the freeway on gas mileage and they cranked up every morning, warmed up well and ran all day long.  Sometimes we'd do 600 to 800 miles a day.

You can build a motor to be dependable and do exactly what you want it to.  You simply need to know what it takes to ensure the motor will live. Oiling mods, clearances, deck height, compression, cam, carburetion, tune, ignition type...It all matters.  The motor I drove from Phoenix to Detroit, Michigan and back is pictured below.

ENGINE SPECS I built the motor in the fall of 1994
2110cc  (Bugpack 82mm crank with Porsche rod journals)
BUGPACK Porsche Length H beam rods
Clevite 77 Bearings
Lightend flywhee (12.5lbs)
BERG 90.5s (Thick Crown - with dish in piston)
Dual Port heads done by DEAN LOWRY in 1994
PAUTER CAM
GERMAN FEBI Lifters
New AS21 Case
Deep SCAT Sump
48mm Dellorto's for all around Driving (48IDAs for events and burnout contests)
Berg Carb Linkage
Berg Oil Pump and Full Flow cover
96 Pass Mesa Oil Cooler and fan with owner built air schroud
MSD6AL with MSD Distributor and wires
8.3 to 1 compression
1.4 Rockers
BERG engine breather on alternator stand
(Custom Wiring by Don Bulitta)
13.90 1/4 mile and 100% capable of being driven anywhere at any time

Rick M

[The Ideaman]

rick ive got mike fischer 044 heads with extra porting work done by steve hollingsworth.im thinking theyre pretty good even though ive not seen them

Let me see if I can find flow sheets...

[67worshipper]

cheers luke.i couldnt open the dyno sheet you sent for some reason could you send under another form please