3/16/2026
CYLINDER HEADS
NEWS 3/16/2026
BY THE END OF THE FIRST WEEK OF FEBURARY -
The Rocket-428 core-box was delivered and the cores were started.
The Cope and Drag patterns were picked up by the foundry at my place.
The foundry must wait for the cores to be finished
then casting can be put into the que.
The machine shop has been informed and is ready to get started.
time frame is too loose to spec yet.
Deposit invoices have been mailed or emailed
to each person on the list.
March 6th The foundry picked up the cope and drag pattern boxes
and the "Front Cover Ignition Plate".
BY THE END OF THE FIRST WEEK OF FEBURARY -
The Rocket-428 core-box was delivered and the cores were started.
The Cope and Drag patterns were picked up by the foundry at my place.
The foundry must wait for the cores to be finished
then casting can be put into the que.
The machine shop has been informed and is ready to get started.
time frame is too loose to spec yet.
Deposit invoices have been mailed or emailed
to each person on the list.
March 6th The foundry picked up the cope and drag pattern boxes
and the "Front Cover Ignition Plate".
If you are wavering
here are couple important considerations:
1: Order one now,
even if you're not sure about needing it.
The pricing will never get lower.
If you decide to sell your investment, you should
get your money back plus some.
2: Enjoy the same power
& chambers as my Lion Speed Head III & IV.
3: The Rocket-428
is quite street-able and
ready for hill climbs.
4: While it is possible
that a few finished
heads may be left over,
it has been my experience since 1998,
that we are usually completely
sold out by shipping day.
5: Don't take a chance.
If this is the direction you want to take,
order now!
A $400 deposit will guarantee you get a head.
here are couple important considerations:
1: Order one now,
even if you're not sure about needing it.
The pricing will never get lower.
If you decide to sell your investment, you should
get your money back plus some.
2: Enjoy the same power
& chambers as my Lion Speed Head III & IV.
3: The Rocket-428
is quite street-able and
ready for hill climbs.
4: While it is possible
that a few finished
heads may be left over,
it has been my experience since 1998,
that we are usually completely
sold out by shipping day.
5: Don't take a chance.
If this is the direction you want to take,
order now!
A $400 deposit will guarantee you get a head.
The Rocket-428 High Compression Cylinder head
Cast Aluminum 356-T6,
7:1 Compression Ratio (140-cc)
All Heads Are Dual Plug.
Cast Aluminum 356-T6,
7:1 Compression Ratio (140-cc)
All Heads Are Dual Plug.
This head wins hill climbs!
THE ROCKET 428 HEAD PROJECT IS A GO.
THE ROCKET 428 HEAD PROJECT IS A GO.
Casting and machining time is usually about 4-5 months.
PRICE
$1235.00
includes shipping
IF PAID BY CHECK
All costs and time suggestions are approximate
and could change as we move forward.
ESTIMATED DELIVERY IS JUNE-ISH (+-)
PAYMENT
We accept:
Personal Checks
Cashier’s Checks
Money Orders
(Credit Cards-See Below)
Make Out Checks & Mail To:
YAPP STUDIOS INC.
3860 Cain Run Rd
Batavia OH 45103
CREDIT CARDS & PAYPAL
We charge a 6% handling fee on the $400 deposit ($24)
and on the final balance due.
Scroll DOWN to bottom of page.
513-724-9000
[email protected]
PRICE
$1235.00
includes shipping
IF PAID BY CHECK
All costs and time suggestions are approximate
and could change as we move forward.
ESTIMATED DELIVERY IS JUNE-ISH (+-)
PAYMENT
We accept:
Personal Checks
Cashier’s Checks
Money Orders
(Credit Cards-See Below)
Make Out Checks & Mail To:
YAPP STUDIOS INC.
3860 Cain Run Rd
Batavia OH 45103
CREDIT CARDS & PAYPAL
We charge a 6% handling fee on the $400 deposit ($24)
and on the final balance due.
Scroll DOWN to bottom of page.
513-724-9000
[email protected]
ROCKET-428 CYLINDER HEAD
356-T6 Aluminum, 7:1 CR
all castings are 8 Spark plugs
FOR THOSE NEEDING A FOUR (4) PLUG HEAD
WE HAVE OPTIONAL
"PLUG-SEALS"
The Rocket's combustion chambers are a match of our very successful
Lion Speed Head III & IV.
The extra thick walls hold heat steady for even firing and extra metal is available to those that want to reshape to their own designs. The spark plug positions are designed for maximum flame front and have proven power on the dyno.
Plugs on the driver's side have more power.
All of Charlie Yapp's cylinder heads are custom tested designs.
Lion Speed Head III & IV.
The extra thick walls hold heat steady for even firing and extra metal is available to those that want to reshape to their own designs. The spark plug positions are designed for maximum flame front and have proven power on the dyno.
Plugs on the driver's side have more power.
All of Charlie Yapp's cylinder heads are custom tested designs.
The foundry and machine shop helping me produce this 2026 production run are the same who have done our Rocket-428 in the last run. They know my need for precision and have proven to me that they will do a fantastic Made-In-USA-job.
CREDIT CARD PAYMENTS HERE
Choose "PayPal" or "checkout use your own card"
Choose "PayPal" or "checkout use your own card"
for Credit Card sales
of Rocket Cylinder Heads
click the USA map above
of Rocket Cylinder Heads
click the USA map above