Secrets Magazine INDEX
Updated 4/25/2022
SOLD OUT
WANT ONE? CAN YOU WAIT 4-5 MONTHS?
MAKE A DEPOSIT OF $400

TOTAL PRICE $850 PLUS SHIPPING

Rocket  428 
High  Compression  Cylinder Head  
Deluxe

Yapp Studios Inc
3860 Cain Run Rd
Batavia OH 45103
You will receive a statement back showing amount paid.
Balance will be due at shipping time.

Deposits are non-refundable 
unless we can not produce.
Production time tables are estimates.
Shipping costs and timing are estimates.
Balance is due at shipping time, within 30 days after notice.
Late payment risks losing deposit and product will go to next customer on list.
All heads are 6.5:1CR and can produce 82HP easily
and 110+ HP with all the "secrets".
Heads will be packed with a small bag of loose parts and
the INSTRUCTION sheet with spark plug info.
You will find the sheet between the outer box and the inner cardboard liner.
The Original Rocket 428 Hi-
compression 6.5:1 CR cylinder head for 
Ford Model A and B engines. 
Has dual spark-plug capability.
AVAILABLE in two versions:

1: Original Rocket 428 Deluxe at  . . . . $850 plus ship
Eight spark-plug ready with
12 head nut washers and 4 Plug Seals.

Spark-Plugs
14mm, 3/4" reach, flat seat with ring gaskets not supplied.

Contact Scalded Dog Speed Parts at 513-724-0700 or email your interest to [email protected]


The Rocket 428 Deluxe comes in 2 versions.
Click HERE 
to see more of the Super Deluxe Thruster version
Spark plugs on driver's side are the default position.
Top side plugs come with our custom S.S. Plug Seals.
Of course you don't have to, but when you're ready to go to 8 spark plugs your Rocket 428 will be ready. Smoke'n
Each head has a special water port 1/2" NPT boss on top, ready to accept your hot water gauge or heater.
Above: The special made ring gaskets are for the stainless steel spark hole seals. 
4 of each ship with the head.
Plug seals are available separately for other cylinder heads with dual plugs
 with 14mm 3/4" threads.  $20.00 each
Below are a few of the Rocket 428
cooling down after heat treating.
YAPP STUDIOS INC
3860 CAIN RUN RD
BATAVIA OH 45103

Overseas buyers please contact me for arrangements.
The Water Thruster Pipe is designed to fit the the Rocket 428 Speed Head.
It can be fit to other engines and cylinder head. 
Think V8-60 and 4 cylinder aircraft and more.
Thruster Pipe is also sold separately unmachined . . .$180.00 each plus ship

FEATURES
Fits all Ford Model A, B, G28T, Gaz, British & Canadian
engines 1928-1934
356-T6 fine grained aluminum casting. Polishable.
6.5:1 compression ratio (CR).
Eight (8) spark plug capable for DUAL spark ignitions.
Ships with four (4) spark "plug seals" to run with SINGLE spark ignitions.
Light-weight 24-26 pounds.
Use stock stud sizes and Model A water pump or V-8 pump adapter.
Water port, top rear, for temperature gauge or heater.
Use carbon-fiber-over-steel Model B Ford head gasket (we sell).


COMBUSTION CHAMBER:
Accepts large intake & exhaust valves up to 1.750".
Round 3.98" dia. X 0.060" deep fly-cut protects your pistons.
Runs naturally cooler.
Chambers same as the retired Lion Speed Head IV . .
proven superior performance.
Chambers surrounded with extra metal to
hold heat for more HP.
Spark plugs on side at 45 degree
(prime default position) produce more HP,
than over the valves, with a
best of class flame front.
Optional Dual Spark ignition produces
even more HP and cleaner burn.
Scalded Dog Speed Parts, 3860 Cain  Run Rd, Batavia OH 45103, USA .
Phone (513) 724-0700, EST